Television | History, Components, & Uses

<!doctype html> <html lang="en" class="topic-desktop ui-ie7 ui-ie"> <head prefix="og: https://ogp.me/ns# fb: https://ogp.me/ns/fb#"> <meta charset="utf-8"> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <meta name="viewport" content="width=device-width, initial-scale=1.0" /> <link rel="dns-prefetch" href="https://cdn.britannica.com/mendel-resources/3-133"> <link rel="preconnect" href="https://cdn.britannica.com/mendel-resources/3-133"> <link rel="preload" as="script" href="https://www.googletagservices.com/tag/js/gpt.js" /> <link rel="icon" href="/favicon.png" /> <meta name="description" content="Television (TV), the electronic delivery of moving images and sound from a source to a receiver. Conceived in the early 20th century, television is a vibrant broadcast medium, using the model of broadcast radio to bring news and entertainment to people all over the world." /> <meta name="keywords" content="television, encyclopedia, encyclopeadia, britannica, article" /> <link rel="canonical" href="https://www.britannica.com/technology/television-technology" /> <title>Television | History, Components, & Uses | Britannica</title>  <script> !function(){"use strict";function e(e){const t=e.match(/((?=([a-z0-9._!#$%+^&*()[\]<>-]+))\2@[a-z0-9._-]+\.[a-z0-9._-]+)/gi);return t?t[0]:""}function t(t){return e(a(t.toLowerCase()))}function a(e){return e.replace(/\s/g,"")}async function n(e){const t={sha256Hash:"",sha1Hash:""};if(!("msCrypto"in window)&&"https:"===location.protocol&&"crypto"in window&&"TextEncoder"in window){const a=(new TextEncoder).encode(e),[n,c]=await Promise.all([s("SHA-256",a),s("SHA-1",a)]);t.sha256Hash=n,t.sha1Hash=c}return t}async function s(e,t){const a=await crypto.subtle.digest(e,t);return Array.from(new Uint8Array(a)).map(e=>("00"+e.toString(16)).slice(-2)).join("")}function c(e){let t=!0;return Object.keys(e).forEach(a=>{0===e[a].length&&(t=!1)}),t}function i(e,t,a){e.splice(t,1);const n="?"+e.join("&")+a.hash;history.replaceState(null,"",n)}var o={checkEmail:e,validateEmail:t,trimInput:a,hashEmail:n,hasHashes:c,removeEmailAndReplaceHistory:i,detectEmails:async function(){const e=new URL(window.location.href),a=Array.from(e.searchParams.entries()).map(e=>`=`);let s,o;const r=["adt_eih","sh_kit"];if(a.forEach((e,t)=>{const a=decodeURIComponent(e),[n,c]=a.split("=");if("adt_ei"===n&&(s={value:c,index:t,emsrc:"url"}),r.includes(n)){o={value:c,index:t,emsrc:"sh_kit"===n?"urlhck":"urlh"}}}),s)t(s.value)&&n(s.value).then(e=>{if(c(e)){const t={value:e,created:Date.now()};localStorage.setItem("adt_ei",JSON.stringify(t)),localStorage.setItem("adt_emsrc",s.emsrc)}});else if(o){const e={value:{sha256Hash:o.value,sha1Hash:""},created:Date.now()};localStorage.setItem("adt_ei",JSON.stringify(e)),localStorage.setItem("adt_emsrc",o.emsrc)}s&&i(a,s.index,e),o&&i(a,o.index,e)},cb:"adthrive"};const{detectEmails:r,cb:l}=o;r()}(); </script> <script type="text/javascript" data-type="Init Mendel"> window.$UI = {}; window.Constants = {"LICENSE_URL": "/bps/license","DEFAULT_TEST_VERSION": "A","DEFAULT_STATE": "XX","QUIZ_URL": "/quiz","SPOTLIGHT_BROWSE_URL": "/stories/spotlight","CONTENT_TYPE_TEXT": "text/plain;charset=UTF-8","TOPIC_FACTS_DATA_URL": "/facts","QUIZ_BROWSE_IMAGE_QUIZZES": "images","TOPIC_MEDIA_PATH": "/images-videos","USER_PROFILE_URL": "/user","DEBUG_URL": "/debug","ONE_GOOD_FACT_URL": "/one-good-fact","ERROR_404_URL": "/error404","PROCON_CITED_IN_THE_NEWS_URL": "/procon/ProCon-in-the-News","PROCON_URL": "/procon","TOPIC_PAGE_CONTENT_AJAX_URL": "/topic-content/page","INFINITE_SCROLL_PREFIX_URL": "/scroll","TOPIC_TOP_QUESTION_BROWSE_URL": "/questions","CC_USD": "USD","domain": "britannica.com","PROCON_EDITOR_ID": "12941390","SURVEY_URL": "/survey","CATEGORY_BROWSE_URL": "/browse","STORY_BROWSE_URL": "/stories","COUNTRY_US": "US","OPEN_MEDIA_OVERLAY_PARAMETER": "/media","NEWSLETTER_SUBSCRIPTION_URL": "/newsletter-subscription","MAINTENANCE_ERROR_URL": "https://maintenance.eb.com","IMARS_EDITOR_ID": "12365882","PROFILE_EB_EDITOR_URL": "/editor","WEB_INF_RESOURCES_PATH": "WEB-INF/resources","AI_ABOUT_PAGE_URL": "/about-britannica-ai","TOPIC_ADDITIONAL_INFO_PATH": "/additional-info","SUDOKU_GAME_URL": "/games/sudoku","CC_INR": "INR","ARTICLE_PRINT_URL": "/print/article","FIRST_EDITION_URL": "/subscriber/firstedition","WW1_PORTAL_URL": "/discover/World-War-I","MENDEL_COOKIE": "__mendel","topicUrlClasses": "[topic, animal, art, biography, event, place, plant, science, sports, technology, procon, money]","DEMYSTIFIED_BROWSE_URL": "/stories/demystified","LIST_BROWSE_URL": "/list/browse","PROFILE_EXPERT_URL": "/contributor","ASSEMBLY_IMAGE_URL": "/image/assembly","DAY_IN_HISTORY_URL": "/on-this-day","DEFAULT_CURRENCY": "USD","CONTENT_TYPE_XML": "text/xml;charset=UTF-8","PORTAL_FINANCE_BROWSE_URL_PREFIX": "/money/browse","MONEY_IMARS_CATEGORY": "13000","AJAX_PREFIX_URL": "/ajax","TOPIC_BROWSE_URL": "/topic-browse","MARKETING_CONTENT": "/marketing-content","ENV_RUNTIME": "runtime","GALLERY_URL": "/gallery","topicUrlClassesList": "topic|animal|art|biography|event|place|plant|science|sports|technology|procon","CONTENT_TYPE_HTML": "text/html;charset=UTF-8","ENV_LOCAL": "override","MEDIA_OVERLAY_URL": "/media-overlay","CHATBOT_PAGE_URL": "/chatbot","NEWSLETTER_PAGE_URL": "/newsletters","ENV_DEV": "development","MEDIA_URL": "/media","TOPIC_TOP_QUESTION_URL": "/question","PORTAL_FINANCE_URL_PREFIX": "/money","PODCASTS_URL": "/podcasts","STAND_ALONE_VIDEO_URL": "/video","MORE_ON_THIS_DAY_URL": "/more-on-this-day","TOPIC_QUOTES_URL": "/quotes","SEARCH_PAGE_URL": "/search","PROCON_CLASS": "PROCON","KUSTOM_MENDEL_APPLICATION_ID": "1","TOPIC_CONTENT_AJAX_URL": "/topic-content/topic","ENV_BRANCH": "branch","ERROR_URL": "/error","MAIN_VERSION": "mainVersion","TOPIC_COLLECTION_URL": "/summary","LOGINBOX_URL": "/auth/loginbox","PROCON_DEBATE_TOPICS_URL": "/procon/Debate-Topics","ONE_GOOD_FACT_BROWSE_URL": "/one-good-fact/all-good-facts","QUIZ_BROWSE_URL": "/quiz/browse","BIO_BROWSE_URL": "/browse/biographies","LIST_URL": "/list","TIGHTROPE_QUIZ_URL": "/quiz/tightrope","ALPHA_BROWSE_URL": "/sitemap","CONTENT_TYPE_JSON": "application/json","DICTIONARY_URL": "/dictionary","COBRAND_IMAGE_URL": "/image/cobrand","PROCON_IN_THE_NEWS_URL": "/procon/pro-and-con-issues-in-the-news","PROCON_BROWSE_URL": "/procon","QUIZ_BROWSE_VOCAB_QUIZZES": "vocabulary-quizzes","SUBMISSION_URL": "/submission","EB_LOG_OUT": "/auth2/logout","ENV_PRODUCTION": "production","EXPLORE_PORTAL_URL": "/explore","TOPIC_AJAX_URL": "/ajax/topic","TOPIC_SUMMARY_BROWSE_URL": "/summaries","WTFACT_BROWSE_URL": "/stories/wtfact","VIDEO_CHANNEL_URL": "/videos","GALLERY_BROWSE_URL": "/gallery/browse","CACHE_URL": "/cache","PROCON_ABOUT_URL": "/procon/About-ProCon","COMPANION_BROWSE_URL": "/stories/companion","MEDIA_FOLDER": "/eb-media","SHOW_ALL_CONTRIBUTORS": "/additional-info#contributors","BRITANNICA_EDITORS_ID": "4419","ENV_CACHE_DISABLED": "mendelCache","CALCULATORS_BROWSE_URL": "/calculators","STORY_URL": "/story","DEFAULT_COUNTRY": "US","NAVBAR_URL": "/ajax/navbar","EB_LOGIN_URL": "/auth/eb-login","NEW_ARTICLES_URL": "/new-articles",}; window.CDN = "https://cdn.britannica.com"; window.CAM_SETTINGS_URL = "https://cam.britannica.com/settings"; window.CAM_LOGIN_URL = "https://cam.britannica.com/login"; window.CAM_SIGN_UP_URL = "https://cam.britannica.com/registration" window.Mendel = { "config" : { "domain": "britannica.com", "page": "Topic", "videoPlayerId": "UyMCoK2v", "sharedUrl": "https://www.britannica.com/technology/television-technology", "amuselabsUrl": "https://cdn3.amuselabs.com", "resourcesPrefixUrl": "https://cdn.britannica.com/mendel-resources/3-133/[url]?v=3.133.48", "date": 20250303, "userInfo": { "type": "ANONYMOUS" ,"currency": "AUUS" ,"country": "SG" ,"state": "XX" ,"timezone": "Asia/Singapore" ,"bcomId": "-7535323640338681127" ,"hasAds": true ,"testVersion": "B" ,"adsTestVersion": "B" ,"consumerId": "" ,"instId": "" ,"consumerUserName": "" ,"instUserName": "" ,"cognito": null }, "tvs":{ "r":[25,25,25,25], "a": [25,25,45,5]}, "isLoggedInAsUser": false, "isPhone": false, "isDesktop": true, "logoutUrl": "/auth2/logout", "selfServiceUrl": "https://myaccount.britannica.com", "cdnUrl": "https://cdn.britannica.com", "chatbotApi": "https://www.britannica.com/chat-api", "fetchOffset": 800, "mendelCookieName": "__mendel", "mendelCookie": {"surveyShown":false,"visitedTopicId":1262241,"currentDate":20250303}, "autocompleteToSearchPage": false,"topicUrl": "https://www.britannica.com/technology/television-technology", "freeTopicReason": "NO_REFERRER", "topicId": 1262241, "template": "DESKTOP", "type": "CORE", "hasToc": true, "chatbotApi": "https://www.britannica.com/chat-api", "showPreview": false, }, "GA": {"leg":"B","adLeg":"B","userType":"ANONYMOUS","pageType":"Topic","articleTemplateType":"PAGINATED","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":true,"hasAiTopQuestions":false,"hasSimplifyButton":false} }; </script> <meta property="fb:app_id" content="1887621861548296"/ <meta name="twitter:card" content="summary_large_image" /> <meta name="twitter:site" content="@britannica" /> <meta name="twitter:image" content="https://cdn.britannica.com/97/6897-050-FF2A9614/electron-guns-color-television-picture-tube-right.jpg" /> <meta name="twitter:description" content="Television (TV), the electronic delivery of moving images and sound from a source to a receiver. Conceived in the early 20th century, television is a vibrant broadcast medium, using the model of broadcast radio to bring news and entertainment to people all over the world."/> <meta property="og:type" content="ARTICLE"/> <meta property="og:title" content="Television | History, Components, & Uses | Britannica"/> <meta property="og:description" content="Television (TV), the electronic delivery of moving images and sound from a source to a receiver. Conceived in the early 20th century, television is a vibrant broadcast medium, using the model of broadcast radio to bring news and entertainment to people all over the world."/> <meta property="og:site_name" content="Encyclopedia Britannica" /> <meta property="og:url" content="https://www.britannica.com/technology/television-technology"/> <meta property="og:image" content="https://cdn.britannica.com/97/6897-050-FF2A9614/electron-guns-color-television-picture-tube-right.jpg" /> <meta property="og:image:type" content="image/jpeg" /> <script type="text/javascript" data-type="init opengraph"> Mendel.openGraph = {"type":"ARTICLE","title":"Television | History, Components, & Uses","description":"Television (TV), the electronic delivery of moving images and sound from a source to a receiver. Conceived in the early 20th century, television is a vibrant broadcast medium, using the model of broadcast radio to bring news and entertainment to people all over the world.","imageUrl":"https://cdn.britannica.com/97/6897-050-FF2A9614/electron-guns-color-television-picture-tube-right.jpg","imageType":"image/jpeg","pageUrl":"https://www.britannica.com/technology/television-technology"}</script> <link rel="preconnect" href="https://fonts.googleapis.com/"> <link rel="dns-prefetch" href="https://fonts.googleapis.com/" > <link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons"> <link href="https://cdn.britannica.com/mendel-resources/3-133/dist/vendor-bundle.css?v=3.133.48" rel="stylesheet" /> <link href="https://cdn.britannica.com/mendel-resources/3-133/dist/mendel-css.css?v=3.133.48" rel="stylesheet" /> <link href="https://cdn.britannica.com/mendel-resources/3-133/dist/topic-page.css?v=3.133.48" rel="stylesheet" /> <script type="text/javascript"> if (self !== top) { top.location = self.location; } </script> <script src="https://cdn.britannica.com/mendel-resources/3-133/js/at.js?v=3.133.48" async ></script> <script> dataLayer = []; </script> <script type="text/javascript">(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start': new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0], j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src= '//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f); })(window,document,'script','dataLayer','GTM-5W6NC8'); </script> <meta name="last-modified" content="2025-01-21" /> <script type="application/ld+json"> {"headline":"Television | History, Components, & Uses","image":{"url":"https://cdn.britannica.com/97/6897-050-FF2A9614/electron-guns-color-television-picture-tube-right.jpg","@type":"ImageObject"},"author":[{"name":"David E. Fisher","url":"https://www.britannica.com/contributor/David-E-Fisher/5439","@type":"Person"},{"name":"Marshall Jon Fisher","url":"https://www.britannica.com/contributor/Marshall-Jon-Fisher/5440","@type":"Person"}],"keywords":"television","wordcount":20679,"url":"https://www.britannica.com/technology/television-technology","datePublished":"1999-07-26T00:00:00Z","dateModified":"2025-01-21T00:00:00Z","description":"Television (TV), the electronic delivery of moving images and sound from a source to a receiver. Conceived in the early 20th century, television is a vibrant broadcast medium, using the model of broadcast radio to bring news and entertainment to people all over the world.","publisher":{"name":"Encyclopedia Britannica","@type":"Organization","logo":{"url":"https://corporate.britannica.com/wp-content/themes/eb-corporate/_img/logo.png","@type":"ImageObject"}},"@context":"https://schema.org","@type":"article"} </script> </head> <body data-leg="B" class="new-topic topic-desktop first-page-true user-ANONYMOUS user-ads md-desktop leg-b b-ie">  <script>Mendel.config.adProvider='cafemedia';</script> <script data-no-optimize="1" data-cfasync="false"> (function(w, d) { w.adthrive = w.adthrive || {}; w.adthrive.cmd = w. adthrive.cmd || []; w.adthrive.plugin = 'adthrive-ads-manual'; w.adthrive.host = 'ads.adthrive.com';var s = d.createElement('script'); s.async = true; s.referrerpolicy='no-referrer-when-downgrade'; s.src = 'https://' + w.adthrive.host + '/sites/61575e5c934c481d714b3ca9/ads.min.js?referrer=' + w.encodeURIComponent(w.location.href) + '&cb=' + (Math.floor(Math.random() * 100) + 1); var n = d.getElementsByTagName('script')[0]; n.parentNode.insertBefore(s, n); })(window, document); </script> <div class="ie-warning d-flex align-items-center align-self-center justify-content-center site-alert bg-orange"> <div> You are using an <strong>outdated</strong> browser. Please <a class="text-white text-underscore" href="https://browsehappy.com/">upgrade your browser</a> to improve your experience and security. </div> </div> <script id="json-navbar-info" type="application/json"> {"topSectionLinks":[{"title":"Ask the Chatbot","url":"/chatbot","navbarId":"CHATBOT"},{"title":"Games & Quizzes","url":"/quiz/browse","navbarId":"QUIZZES"},{"title":"History & Society","url":"/History-Society","navbarId":"HISTORY"},{"title":"Science & Tech","url":"/Science-Tech","selected":true,"navbarId":"SCIENCE"},{"title":"Biographies","url":"/Biographies","navbarId":"BIOS"},{"title":"Animals & Nature","url":"/Animals-Nature","navbarId":"ANIMALS"},{"title":"Geography & Travel","url":"/Geography-Travel","navbarId":"GEOGRAPHY"},{"title":"Arts & Culture","url":"/Arts-Culture","navbarId":"ART"},{"title":"ProCon","url":"/procon","navbarId":"PROCON"},{"title":"Money","url":"/money","navbarId":"MONEY"},{"title":"Videos","url":"/videos","navbarId":"VIDEOS"}],"selectedSuperCategory":{"id":6,"title":"Science & Tech","url":"Science-Tech","description":"Explore science and technology; astronomy; biology; chemistry; earth science; mathematics; physics; technology, agriculture, cars, computers, engineering, industry, inventions, communication","keywords":"astronomy; biology; chemistry; earth science; mathematics; physics; technology, agriculture, cars, computers, engineering, industry, inventions, communication","classId":"SCIENCE","sortOrder":2},"selectedNavbarLink":{"title":"Science & Tech","url":"/Science-Tech","selected":true,"navbarId":"SCIENCE"}} </script> <script id="json-hamburger-menu" type="application/json"> {"britannicaMenu1":[{"title":"Home","url":"/"},{"title":"History & Society","url":"/History-Society"},{"title":"Science & Tech","url":"/Science-Tech"},{"title":"Biographies","url":"/Biographies"},{"title":"Animals & Nature","url":"/Animals-Nature"},{"title":"Geography & Travel","url":"/Geography-Travel"},{"title":"Arts & Culture","url":"/Arts-Culture"},{"title":"ProCon","url":"/procon"},{"title":"Money","url":"/money"}],"britannicaMenu2":[{"title":"Games & Quizzes","url":"/quiz/browse"},{"title":"Videos","url":"/videos"},{"title":"On This Day","url":"/on-this-day"},{"title":"One Good Fact","url":"/one-good-fact"},{"title":"Dictionary","url":"/dictionary"},{"title":"New Articles","url":"/new-articles"}],"browseByCategory":[{"title":{"id":5,"title":"History & Society","url":"/History-Society"},"links":[{"title":"Lifestyles & Social Issues","url":"/browse/Lifestyles-Social-Issues"},{"title":"Philosophy & Religion","url":"/browse/Philosophy-Religion"},{"title":"Politics, Law & Government","url":"/browse/Politics-Law-Government"},{"title":"World History","url":"/browse/World-History"}]},{"title":{"id":6,"title":"Science & Tech","url":"/Science-Tech"},"links":[{"title":"Health & Medicine","url":"/browse/Health-Medicine"},{"title":"Science","url":"/browse/Science"},{"title":"Technology","url":"/browse/Technology"}]},{"title":{"id":3,"title":"Biographies","url":"/Biographies"},"links":[{"title":"Browse Biographies","url":"/browse/biographies"}]},{"title":{"id":1,"title":"Animals & Nature","url":"/Animals-Nature"},"links":[{"title":"Birds, Reptiles & Other Vertebrates","url":"/browse/Birds-Reptiles-Vertebrates"},{"title":"Bugs, Mollusks & Other Invertebrates","url":"/browse/Bugs-Mollusks-Invertebrates"},{"title":"Environment","url":"/browse/Environment"},{"title":"Fossils & Geologic Time","url":"/browse/Fossil-Geologic-Time"},{"title":"Mammals","url":"/browse/Mammals"},{"title":"Plants","url":"/browse/Plants"}]},{"title":{"id":4,"title":"Geography & Travel","url":"/Geography-Travel"},"links":[{"title":"Geography & Travel","url":"/browse/Geography-Travel"}]},{"title":{"id":2,"title":"Arts & Culture","url":"/Arts-Culture"},"links":[{"title":"Entertainment & Pop Culture","url":"/browse/Entertainment-Pop-Culture"},{"title":"Literature","url":"/browse/Literature"},{"title":"Sports & Recreation","url":"/browse/Sports-Recreation"},{"title":"Visual Arts","url":"/browse/Visual-Arts"}]}],"browseByFeature":[{"title":"Companions","url":"/stories/companion"},{"title":"Demystified","url":"/stories/demystified"},{"title":"Image Galleries","url":"/gallery/browse"},{"title":"Lists","url":"/list/browse"},{"title":"Podcasts","url":"/podcasts"},{"title":"Spotlight","url":"/stories/spotlight"},{"title":"Summaries","url":"/summary"},{"title":"The Forum","url":"/stories/the-forum"},{"title":"Top Questions","url":"/question"},{"title":"#WTFact","url":"/stories/wtfact"}],"moreFromBritannica":[{"title":"Britannica Kids","url":"https://kids.britannica.com/","newTab":true}],"menuType":"DEFAULT"} </script> <header id="header" class="bg-navy-dark"> <div class="global-nav-top-bar"> <div class="grid gx-0 h-100 justify-content-between align-items-center container-lg mx-auto p-0 position-relative"> <div class="d-flex align-items-center"> <button class="d-flex align-items-center justify-self-start js-toggle js-toggle-hamburger btn btn-link link-white btn-sm rounded-0 p-10"> <div class="hamburger-tooltip"> <em class="material-icons d-inline-block font-24" id="nav-toggle" data-icon="menu"></em> </div> <em class="material-icons d-inline-block font-24 global-nav-search-icon" id="nav-search-icon" data-icon="search" ></em> </button> <a href="/" class="d-flex align-items-center justify-content-center ml-10"> <img loading="lazy" src="https://cdn.britannica.com/mendel/eb-logo/MendelNewThistleLogo.png" alt="Encyclopedia Britannica" class="global-nav-logo global-nav-logo-left" /> </a> <div class="global-nav-top-search-bar global-nav-top-search-container global-nav-search-container" id="global-nav-top-search-bar"> <form method="get" action="/search" id="global-nav-search" class="md-search-form m-0 global-nav-search-bar-small"> <div class="search-box position-relative col-100"> <label class="sr-only" for="global-nav-search-query">Search Britannica</label> <input name="query" id="global-nav-search-query" placeholder="Search Britannica..." class="form-control form-control-lg rounded-lg font-16 search-query pl-20 pr-70 shadow-sm" maxlength="200" autocomplete="off" aria-label="Search Britannica" /> <button class="search-reset-btn btn btn-link px-10 position-absolute top-0 h-100 d-none" type="reset"> <em class="material-icons" data-icon="close"></em> </button> <button class="search-submit btn btn-link text-blue px-10 position-absolute top-0 right-0 h-100" type="submit" disabled> <span class="sr-only">Click here to search</span> <em class="material-icons search-icon" data-icon="search"></em> </button> </div> </form> </div> </div> <a href="/" class="d-flex align-items-center justify-content-center"> <img loading="lazy" src="https://cdn.britannica.com/mendel/eb-logo/MendelNewThistleLogo.png" alt="Encyclopedia Britannica" class="global-nav-center global-nav-logo non-homepage-logo" /> </a> <form method="get" action="/search" id="global-nav-search" class="md-search-form m-0 global-nav-search-bar-small global-nav-center search global-nav-center-search-container"> <div class="search-box position-relative col-100"> <label class="sr-only" for="global-nav-search-query">Search Britannica</label> <input name="query" id="global-nav-search-query" placeholder="Search Britannica..." class="form-control form-control-lg rounded-lg font-16 search-query pl-20 pr-70 shadow-sm" maxlength="200" autocomplete="off" aria-label="Search Britannica" /> <button class="search-reset-btn btn btn-link px-10 position-absolute top-0 h-100 d-none" type="reset"> <em class="material-icons" data-icon="close"></em> </button> <button class="search-submit btn btn-link text-blue px-10 position-absolute top-0 right-0 h-100" type="submit" disabled> <span class="sr-only">Click here to search</span> <em class="material-icons search-icon" data-icon="search"></em> </button> </div> </form> <div class="col-35 col-sm-auto text-right order-3 mr-lg-15 align-items-center d-flex justify-content-end"> <div class="d-none d-md-inline-block"> <SPAN class="marketing-HEADER_SUBSCRIPTION_DESKTOP2 marketing-content" data-marketing-id="HEADER_SUBSCRIPTION_DESKTOP2"><a href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=global-nav&utm_campaign=evergreen-cap" class="subscribe-link btn btn-sm btn-orange py-5 mr-10" target="_blank" rel="noopener"> SUBSCRIBE </a></SPAN></div> <div class="d-inline-block d-md-none mr-5 mr-sm-10"> <SPAN class="marketing-HEADER_SUBSCRIPTION_MOBILE marketing-content" data-marketing-id="HEADER_SUBSCRIPTION_MOBILE"><a href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=global-nav-mobile&utm_campaign=evergreen" class="subscribe-link btn btn-xs btn-orange p-5" target="_blank" rel="noopener"> SUBSCRIBE </a></SPAN></div> <button class="js-toggle-user-dropdown js-toggle btn btn-sm btn-link link-white rounded-0 px-md-15 pl-5 pr-5"> <span class="d-none d-md-inline-block mr-5">Login</span> <em class="material-icons d-inline-block d-md-none font-16 font-sm-20" data-icon="account_circle"></em> <div class="d-none dropdown-menu-subscription-link">https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=nav-login-box&utm_campaign=evergreen</div> <em class="material-icons inactive-icon d-inline-block font-18" data-icon="keyboard_arrow_down"></em> <em class="material-icons active-icon d-inline-block font-18" data-icon="keyboard_arrow_up"></em> </button> </div> </div> </div> <div class="d-none hamburger-menu-subscription-link"><DIV class="marketing-HAMBURGER_MENU_CTA marketing-content" data-marketing-id="HAMBURGER_MENU_CTA"><a href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=hamburger-menu&utm_campaign=evergreen" class="subscribe-link btn btn-sm btn-orange py-5" target="_blank"> SUBSCRIBE </a></DIV></div> <div id="global-nav-react"> <div class="d-none"> <ul> <li><a href="/">Home</a></li> <li><a href="/History-Society">History & Society</a></li> <li><a href="/Science-Tech">Science & Tech</a></li> <li><a href="/Biographies">Biographies</a></li> <li><a href="/Animals-Nature">Animals & Nature</a></li> <li><a href="/Geography-Travel">Geography & Travel</a></li> <li><a href="/Arts-Culture">Arts & Culture</a></li> <li><a href="/procon">ProCon</a></li> <li><a href="/money">Money</a></li> </ul> <ul> <li><a href="/quiz/browse">Games & Quizzes</a></li> <li><a href="/videos">Videos</a></li> <li><a href="/on-this-day">On This Day</a></li> <li><a href="/one-good-fact">One Good Fact</a></li> <li><a href="/dictionary">Dictionary</a></li> <li><a href="/new-articles">New Articles</a></li> </ul> <a href="/History-Society">History & Society</a> <ul> <li><a href="/browse/Lifestyles-Social-Issues">Lifestyles & Social Issues</a></li> <li><a href="/browse/Philosophy-Religion">Philosophy & Religion</a></li> <li><a href="/browse/Politics-Law-Government">Politics, Law & Government</a></li> <li><a href="/browse/World-History">World History</a></li> </ul> <a href="/Science-Tech">Science & Tech</a> <ul> <li><a href="/browse/Health-Medicine">Health & Medicine</a></li> <li><a href="/browse/Science">Science</a></li> <li><a href="/browse/Technology">Technology</a></li> </ul> <a href="/Biographies">Biographies</a> <ul> <li><a href="/browse/biographies">Browse Biographies</a></li> </ul> <a href="/Animals-Nature">Animals & Nature</a> <ul> <li><a href="/browse/Birds-Reptiles-Vertebrates">Birds, Reptiles & Other Vertebrates</a></li> <li><a href="/browse/Bugs-Mollusks-Invertebrates">Bugs, Mollusks & Other Invertebrates</a></li> <li><a href="/browse/Environment">Environment</a></li> <li><a href="/browse/Fossil-Geologic-Time">Fossils & Geologic Time</a></li> <li><a href="/browse/Mammals">Mammals</a></li> <li><a href="/browse/Plants">Plants</a></li> </ul> <a href="/Geography-Travel">Geography & Travel</a> <ul> <li><a href="/browse/Geography-Travel">Geography & Travel</a></li> </ul> <a href="/Arts-Culture">Arts & Culture</a> <ul> <li><a href="/browse/Entertainment-Pop-Culture">Entertainment & Pop Culture</a></li> <li><a href="/browse/Literature">Literature</a></li> <li><a href="/browse/Sports-Recreation">Sports & Recreation</a></li> <li><a href="/browse/Visual-Arts">Visual Arts</a></li> </ul> <ul> <li><a href="/stories/companion">Companions</a></li> <li><a href="/stories/demystified">Demystified</a></li> <li><a href="/gallery/browse">Image Galleries</a></li> <li><a href="/list/browse">Lists</a></li> <li><a href="/podcasts">Podcasts</a></li> <li><a href="/stories/spotlight">Spotlight</a></li> <li><a href="/summary">Summaries</a></li> <li><a href="/stories/the-forum">The Forum</a></li> <li><a href="/question">Top Questions</a></li> <li><a href="/stories/wtfact">#WTFact</a></li> </ul> <ul> <li><a href="https://kids.britannica.com/">Britannica Kids</a></li> </ul> </div> </div> </header> <div class="bg-navy-dark"> <div class="container-lg p-0 d-flex justify-content-center global-nav-categories-bar overflow-hidden"> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 global-nav-slider category-snap-slider"> <div class="slider-container js-slider-container overflow-hidden d-flex font-14 overflow-hidden text-nowrap mx-5"> <a class="nav-bar-category mx-5 category-link-CHATBOT " href="/chatbot">Ask the Chatbot</a> <a class="nav-bar-category mx-5 category-link-QUIZZES " href="/quiz/browse">Games & Quizzes</a> <a class="nav-bar-category mx-5 category-link-HISTORY " href="/History-Society">History & Society</a> <a class="nav-bar-category mx-5 category-link-SCIENCE selected selected" href="/Science-Tech">Science & Tech</a> <a class="nav-bar-category mx-5 category-link-BIOS " href="/Biographies">Biographies</a> <a class="nav-bar-category mx-5 category-link-ANIMALS " href="/Animals-Nature">Animals & Nature</a> <a class="nav-bar-category mx-5 category-link-GEOGRAPHY " href="/Geography-Travel">Geography & Travel</a> <a class="nav-bar-category mx-5 category-link-ART " href="/Arts-Culture">Arts & Culture</a> <a class="nav-bar-category mx-5 category-link-PROCON " href="/procon">ProCon</a> <a class="nav-bar-category mx-5 category-link-MONEY " href="/money">Money</a> <a class="nav-bar-category mx-5 category-link-VIDEOS " href="/videos">Videos</a> </div> <button disabled class="prev-button js-prev-button position-absolute btn btn-circle shadow btn-blue " aria-label="Previous"> <span class="material-icons md-24" data-icon="keyboard_arrow_left"></span> </button> <button disabled class="next-button js-next-button position-absolute btn btn-circle shadow btn-blue " aria-label="Next"> <span class="material-icons md-24" data-icon="keyboard_arrow_right"></span> </button> </div> </div> </div> <main> <div class="md-page-wrapper"> <div id="content" class="md-content"> <div class="md-article-container template-desktop infinite-pagination"> <div class="infinite-scroll-container article last"> <script> Object.assign( window.Mendel.config, { "infiniteScrollList": [{"p":21,"t":1262241},{"p":1,"t":2223190},{"p":1,"t":126803},{"p":1,"t":368234},{"p":1,"t":1995158},{"p":27,"t":1513870},{"p":1,"t":1369757},{"p":1,"t":2220027},{"p":1,"t":306742},{"p":1,"t":1932691}], "sequence": 1, "topics": {} }); </script> <article class="article-content container-lg qa-content px-0 pt-0 pb-40 py-lg-20 content md-expanded" data-topic-id="1262241"> <div class="grid gx-0"> <div class="col-auto"> <div class="topic-left-rail md-article-drawer position-relative d-flex border-right-sm border-left-sm open"> <div class="drawer d-flex flex-column open"> <div class="left-rail-section-content"> <div class="topic-left-rail-header text-truncate bg-gray-50 position-relative text-right d-flex align-items-center"> <div class="tlr-title px-20 py-15 text-left"> <em class="material-icons text-gray-400 d-lg-none" data-icon="toc"></em> <a class="font-serif font-weight-bold text-black link-blue" href="https://www.britannica.com/technology/television-technology">television</a> </div> <button aria-label="Close" class="js-sections-close-button btn-link btn-sm btn d-lg-none position-absolute top-0 p-10 right-0" > <em class="material-icons font-26" data-icon="close"></em> </button> </div> <div class="section-content pl-10 pr-20 pl-sm-50 pr-sm-60 pl-lg-5 pr-lg-10 pt-10 pt-lg-0 bg-gray-50 clear-catfish-ad"> <div class="toc mb-20"> <div class="font-serif font-14 font-weight-bold mx-15 mb-15 mt-20"> Table of Contents </div> <ul class="list-unstyled my-0" data-level="h1"><li data-target="#ref1"><div class="pl-25"><a class="link-gray-900 w-100" href="/technology/television-technology">Introduction</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref25145"><div class="d-flex align-items-center"><button class="h1-link-drawer-button btn btn-xs btn-circle d-flex rounded" type="button" aria-label="Toggle Heading"><em class="material-icons font-18" data-icon="keyboard_arrow_right"></em></button><a class="w-100 link-gray-900" href="/technology/television-technology#ref25145">The development of television systems</a></div><div class="ml-40 toc-drawer sub-toc-drawer"><ul class="list-unstyled" data-level="h2"><li data-target="#ref25146"><a class="w-100 link-gray-900" href="/technology/television-technology#ref25146">Mechanical systems</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref25147"><a class="w-100 link-gray-900" href="/technology/television-technology/Electronic-systems">Electronic systems</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref25148"><a class="w-100 link-gray-900" href="/technology/television-technology/Colour-television">Colour television</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref235378"><a class="w-100 link-gray-900" href="/technology/television-technology/Digital-television">Digital television</a></li></ul></div></li><li data-target="#ref25149"><div class="d-flex align-items-center"><button class="h1-link-drawer-button btn btn-xs btn-circle d-flex rounded" type="button" aria-label="Toggle Heading"><em class="material-icons font-18" data-icon="keyboard_arrow_right"></em></button><a class="w-100 link-gray-900" href="/technology/television-technology/Principles-of-television-systems">Principles of television systems</a></div><div class="ml-40 toc-drawer sub-toc-drawer"><ul class="list-unstyled" data-level="h2"><li data-target="#ref235323"><a class="w-100 link-gray-900" href="/technology/television-technology/Principles-of-television-systems#ref235323">The television picture</a><ul class="list-unstyled" data-level="h3"><li data-target="#ref235324"><a class="w-100 link-gray-900" href="/technology/television-technology/Principles-of-television-systems#ref235324">Human perception of motion</a></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235325" class="has-children"><a class="w-100 link-gray-900" href="/technology/television-technology/Principles-of-television-systems#ref235325">Image analysis</a><ul class="list-unstyled" data-level="h4"><li data-target="#ref235326"><a class="w-100 link-gray-900" href="/technology/television-technology/Principles-of-television-systems#ref235326">Flicker</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235327"><a class="w-100 link-gray-900" href="/technology/television-technology/Resolution">Resolution</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235328"><a class="w-100 link-gray-900" href="/technology/television-technology/Resolution#ref235328">Picture shape</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235329"><a class="w-100 link-gray-900" href="/technology/television-technology/Resolution#ref235329">Scanning</a></li></ul></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235330" class="has-children"><a class="w-100 link-gray-900" href="/technology/television-technology/The-scanning-pattern">The scanning pattern</a><ul class="list-unstyled" data-level="h4"><li data-target="#ref235331"><a class="w-100 link-gray-900" href="/technology/television-technology/The-scanning-pattern#ref235331">Interlaced lines</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235332"><a class="w-100 link-gray-900" href="/technology/television-technology/The-scanning-pattern#ref235332">Deflection signals</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235333"><a class="w-100 link-gray-900" href="/technology/television-technology/The-scanning-pattern#ref235333">Synchronization signals</a></li></ul></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235334" class="has-children"><a class="w-100 link-gray-900" href="/technology/television-technology/The-picture-signal">The picture signal</a><ul class="list-unstyled" data-level="h4"><li data-target="#ref235335"><a class="w-100 link-gray-900" href="/technology/television-technology/The-picture-signal#ref235335">Wave form</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235336"><a class="w-100 link-gray-900" href="/technology/television-technology/The-picture-signal#ref235336">Distortion and interference</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235337"><a class="w-100 link-gray-900" href="/technology/television-technology/Bandwidth-requirements">Bandwidth requirements</a></li></ul></li></ul></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref235338"><a class="w-100 link-gray-900" href="/technology/television-technology/Bandwidth-requirements#ref235338">Compatible colour television</a><ul class="list-unstyled" data-level="h3"><li data-target="#ref235339"><a class="w-100 link-gray-900" href="/technology/television-technology/Basic-principles-of-compatible-colour-The-NTSC-system">Basic principles of compatible colour: The NTSC system</a></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235340" class="has-children"><a class="w-100 link-gray-900" href="/technology/television-technology/European-colour-systems">European colour systems</a><ul class="list-unstyled" data-level="h4"><li data-target="#ref235341"><a class="w-100 link-gray-900" href="/technology/television-technology/European-colour-systems#ref235341">PAL</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235342"><a class="w-100 link-gray-900" href="/technology/television-technology/European-colour-systems#ref235342">SECAM</a></li></ul></li></ul></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref235343"><a class="w-100 link-gray-900" href="/technology/television-technology/European-colour-systems#ref235343">Digital television</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref235344"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-transmission-and-reception">Television transmission and reception</a><ul class="list-unstyled" data-level="h3"><li data-target="#ref235345" class="has-children"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-transmission-and-reception#ref235345">Transmission</a><ul class="list-unstyled" data-level="h4"><li data-target="#ref235346"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-transmission-and-reception#ref235346">Generating the colour picture signal</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235347"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-transmission-and-reception#ref235347">The carrier signal</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235348"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-transmission-and-reception#ref235348">The sound signal</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235349"><a class="w-100 link-gray-900" href="/technology/television-technology/The-television-channel">The television channel</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235350"><a class="w-100 link-gray-900" href="/technology/television-technology/The-television-channel#ref235350">Broadcast television</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235351"><a class="w-100 link-gray-900" href="/technology/television-technology/The-television-channel#ref235351">Cable television</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235352"><a class="w-100 link-gray-900" href="/technology/television-technology/Direct-broadcast-satellite-television">Direct broadcast satellite television</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235353"><a class="w-100 link-gray-900" href="/technology/television-technology/Direct-broadcast-satellite-television#ref235353">Teletext</a></li></ul></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235354" class="has-children"><a class="w-100 link-gray-900" href="/technology/television-technology/Direct-broadcast-satellite-television#ref235354">Reception</a><ul class="list-unstyled" data-level="h4"><li data-target="#ref235355"><a class="w-100 link-gray-900" href="/technology/television-technology/Basic-receiver-circuits">Basic receiver circuits</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235356"><a class="w-100 link-gray-900" href="/technology/television-technology/Basic-receiver-circuits#ref235356">Controls</a></li></ul></li></ul></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref235357"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-cameras-and-displays">Television cameras and displays</a><ul class="list-unstyled" data-level="h3"><li data-target="#ref235358" class="has-children"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-cameras-and-displays#ref235358">Camera image sensors</a><ul class="list-unstyled" data-level="h4"><li data-target="#ref235359"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-cameras-and-displays#ref235359">Electron tubes</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235360"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-cameras-and-displays#ref235360">Charge-coupled devices</a></li></ul></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235361" class="has-children"><a class="w-100 link-gray-900" href="/technology/television-technology/Television-cameras-and-displays#ref235361">Displays</a><ul class="list-unstyled" data-level="h4"><li data-target="#ref235362"><a class="w-100 link-gray-900" href="/technology/television-technology/Picture-tubes">Picture tubes</a><ul class="list-unstyled" data-level="h5"><li data-target="#ref235363"><a class="w-100 link-gray-900" href="/technology/television-technology/Picture-tubes#ref235363">Basic structure</a></li></ul><ul class="list-unstyled" data-level="h5"><li data-target="#ref235364"><a class="w-100 link-gray-900" href="/technology/television-technology/Picture-tubes#ref235364">Electron guns</a></li></ul><ul class="list-unstyled" data-level="h5"><li data-target="#ref235365"><a class="w-100 link-gray-900" href="/technology/television-technology/Picture-tubes#ref235365">Deflection coils</a></li></ul><ul class="list-unstyled" data-level="h5"><li data-target="#ref235366"><a class="w-100 link-gray-900" href="/technology/television-technology/Shadow-masks-and-aperture-grilles">Shadow masks and aperture grilles</a></li></ul></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235367"><a class="w-100 link-gray-900" href="/technology/television-technology/Shadow-masks-and-aperture-grilles#ref235367">Liquid crystal displays</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235368"><a class="w-100 link-gray-900" href="/technology/television-technology/Plasma-display-panels">Plasma display panels</a></li></ul></li></ul></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref235369"><a class="w-100 link-gray-900" href="/technology/television-technology/Plasma-display-panels#ref235369">Video recording</a><ul class="list-unstyled" data-level="h3"><li data-target="#ref235370"><a class="w-100 link-gray-900" href="/technology/television-technology/Plasma-display-panels#ref235370">Magnetic tape</a></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235371"><a class="w-100 link-gray-900" href="/technology/television-technology/Video-discs">Video discs</a></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235372"><a class="w-100 link-gray-900" href="/technology/television-technology/Video-discs#ref235372">Special techniques</a></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235373"><a class="w-100 link-gray-900" href="/technology/television-technology/Video-discs#ref235373">Flying spot scanner</a></li></ul><ul class="list-unstyled" data-level="h3"><li data-target="#ref235374" class="has-children"><a class="w-100 link-gray-900" href="/technology/television-technology/Motion-picture-recording">Motion-picture recording</a><ul class="list-unstyled" data-level="h4"><li data-target="#ref235375"><a class="w-100 link-gray-900" href="/technology/television-technology/Motion-picture-recording#ref235375">The continuous projector</a></li></ul><ul class="list-unstyled" data-level="h4"><li data-target="#ref235376"><a class="w-100 link-gray-900" href="/technology/television-technology/Motion-picture-recording#ref235376">The intermittent projector</a></li></ul></li></ul></li></ul></div></li></ul> <a class="toc-extra-link link-gray-900" href="https://www.britannica.com/technology/television-technology/additional-info">References & Edit History</a> <a class="toc-extra-link link-gray-900" href="/facts/television-technology">Related Topics</a> </div> <div class="tlr-media-slider pb-10 mb-30"> <a class="section-header link-gray-900 font-serif font-14 font-weight-bold mb-10 mx-10" href="https://www.britannica.com/technology/television-technology/images-videos">Images</a> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 "> <div class="slider-container js-slider-container overflow-hidden d-flex overflow-hidden text-nowrap ml-15"> <a href="https://cdn.britannica.com/97/6897-050-FF2A9614/electron-guns-color-television-picture-tube-right.jpg" data-href="/media/1/1262241/788" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/97/6897-004-C4D7843D/electron-guns-color-television-picture-tube-right.jpg" alt="colour television picture tube" height="50" /> </a> <a href="https://cdn.britannica.com/15/70015-004-007D6A99/John-Logie-Baird-Stookie-Bill-television-transmitter.jpg" data-href="/media/1/1262241/60151" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/15/70015-004-007D6A99/John-Logie-Baird-Stookie-Bill-television-transmitter.jpg" alt="John Logie Baird with television transmitter" height="50" /> </a> <a href="https://cdn.britannica.com/88/6888-050-33880C71/television-camera-tube-iconoscope-Iconoscope-VK-globules-1939-broadcasting.jpg" data-href="/media/1/1262241/48982" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/88/6888-004-9F178267/television-camera-tube-iconoscope-Iconoscope-VK-globules-1939-broadcasting.jpg" alt="iconoscope television camera tube" height="50" /> </a> <a href="https://cdn.britannica.com/16/70016-004-9C058FA5/Production-line-CT-100-Radio-Corporation-of-America-1954.jpg" data-href="/media/1/1262241/60153" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/16/70016-004-9C058FA5/Production-line-CT-100-Radio-Corporation-of-America-1954.jpg" alt="production line for the RCA CT-100 television" height="50" /> </a> <a href="https://cdn.britannica.com/17/70017-050-E801E785/picture-Picture-tube-aspect-ratios-HDTV-SDTV-broadcasting-television.jpg" data-href="/media/1/1262241/60156" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/17/70017-004-C1041EC7/picture-Picture-tube-aspect-ratios-HDTV-SDTV-broadcasting-television.jpg" alt="picture tube aspect ratios for SDTV and HDTV" height="50" /> </a> <a href="https://cdn.britannica.com/83/6883-050-7E3ECED1/scanning-television-display-field-scan-lines-each-broadcasting.jpg" data-href="/media/1/1262241/775" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/83/6883-004-D53F95F3/scanning-television-display-field-scan-lines-each-broadcasting.jpg" alt="interlaced scanning for standard television display" height="50" /> </a> <a href="https://cdn.britannica.com/84/6884-050-F6044F26/Wave-forms-deflection-scanning-spot-broadcasting-television.jpg" data-href="/media/1/1262241/776" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/84/6884-004-FDFF31BE/Wave-forms-deflection-scanning-spot-broadcasting-television.jpg" alt="wave forms in sequential scanning" height="50" /> </a> <a href="https://cdn.britannica.com/20/70020-050-E5E9D945/Wave-form-television-picture-signal.jpg" data-href="/media/1/1262241/60159" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/20/70020-004-A45162CB/Wave-form-television-picture-signal.jpg" alt="wave form for black-and-white TV" height="50" /> </a> <a href="https://cdn.britannica.com/19/70019-050-8A9239B5/television-signal-luminance-information-carrier-wave-video.jpg" data-href="/media/1/1262241/60158" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/19/70019-004-5CC1614C/television-signal-luminance-information-carrier-wave-video.jpg" alt="composite TV signal" height="50" /> </a> <a href="https://cdn.britannica.com/18/70018-050-7DC418CB/Wave-form-synchronization-signal-end-pulses-series-television.jpg" data-href="/media/1/1262241/60157" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/18/70018-004-EECE95AD/Wave-form-synchronization-signal-end-pulses-series-television.jpg" alt="wave form of vertical synchronization signal" height="50" /> </a> </div> <button disabled class="prev-button js-prev-button position-absolute btn btn-circle shadow btn-blue " aria-label="Previous"> <span class="material-icons md-24" data-icon="keyboard_arrow_left"></span> </button> <button disabled class="next-button js-next-button position-absolute btn btn-circle shadow btn-blue " aria-label="Next"> <span class="material-icons md-24" data-icon="keyboard_arrow_right"></span> </button> </div> </div> <div class="mb-30 tlr-student-links"> <div class="text-gray-900 p-5 font-serif font-14 font-weight-bold mx-10 mb-10"> For Students </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/summary/television-technology"> <img loading="lazy" src="https://cdn.britannica.com/96/77396-004-895151AA/vintage-television-set.jpg?w=200&h=200&c=crop" alt="television" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/summary/television-technology" >television summary</a> </div> </div> </div> <div class="mb-30 tlr-read-next"> <div class="text-gray-900 p-5 font-serif font-14 font-weight-bold mx-10 mb-10"> Read Next </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/history-of-technology-timeline"> <img loading="lazy" src="https://cdn.britannica.com/84/203584-131-357FBE7D/speed-internet-technology-background.jpg?w=200&h=200&c=crop" alt="Abstract vector hi speed internet technology background" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/history-of-technology-timeline" >History of Technology Timeline</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/why-do-television-shows-use-laugh-tracks"> <img loading="lazy" src="https://cdn.britannica.com/29/190729-131-C283A0A9/Human-backs-shooting-auditorium-television-talk-show.jpg?w=200&h=200&c=crop" alt="Human backs in auditorium on shooting of television talk-show" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/why-do-television-shows-use-laugh-tracks" >Why Do Television Shows Use Laugh Tracks?</a> </div> </div> </div> <div class="mb-30 tlr-discover"> <div class="text-gray-900 p-5 font-serif font-14 font-weight-bold mx-10 mb-10"> Discover </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/which-waters-do-you-pass-through-when-you-sail-the-seven-seas"> <img loading="lazy" src="https://cdn.britannica.com/97/196697-131-0155C802/Sailboat-landscape.jpg?w=200&h=200&c=crop" alt="Sailboat against a beautiful landscape" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/which-waters-do-you-pass-through-when-you-sail-the-seven-seas" >Which Waters Do You Pass Through When You “Sail the Seven Seas”?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/what-is-the-ides-of-march"> <img loading="lazy" src="https://cdn.britannica.com/10/189610-131-C06C6A6B/Calendar-march-15th-march-15th.jpg?w=200&h=200&c=crop" alt="Calendar marking march 15th" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/what-is-the-ides-of-march" >What Is the “Ides” of March?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/timeline-of-the-first-opium-war"> <img loading="lazy" src="https://cdn.britannica.com/23/199823-131-346B9183/Chinese-Opium-den.jpg?w=200&h=200&c=crop" alt="Chinese Opium den, 19th Century" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/timeline-of-the-first-opium-war" >Timeline of the First Opium War</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/why-did-the-soviet-union-collapse"> <img loading="lazy" src="https://cdn.britannica.com/45/195145-131-784B0AED/hammer-sickle-star-Ukraine-Pavilion-All-Russia.jpg?w=200&h=200&c=crop" alt="Communism - mosaic hammer and sickle with star on the Pavilion of Ukraine at the All Russia Exhibition Centre (also known as VDNKh) in Moscow. Communist symbol of the former Soviet Union. USSR" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/why-did-the-soviet-union-collapse" >Why Did the Soviet Union Collapse?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/why-are-there-only-28-days-in-february"> <img loading="lazy" src="https://cdn.britannica.com/17/191117-131-1D995EB8/Calendar.jpg?w=200&h=200&c=crop" alt="Calendar showing the month of February" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/why-are-there-only-28-days-in-february" >Why Are There Only 28 Days in February?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/10-best-hockey-players-of-all-time"> <img loading="lazy" src="https://cdn.britannica.com/13/134913-131-D9520745/Ice-Sledge-Hockey-Canada-Cup-USA-ice-2010.jpg?w=200&h=200&c=crop" alt="Ice Sledge Hockey, Hockey Canada Cup, USA (left) vs Canada, 2009. UBC Thunderbird Arena, Vancouver, BC, competition site for Olympic ice hockey and Paralympic ice sledge hockey. Vancouver 2010 Olympic and Paralympic Winter Games, Vancouver Olympics" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/10-best-hockey-players-of-all-time" >10 Best Hockey Players of All Time</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/nostradamus-and-his-prophecies"> <img loading="lazy" src="https://cdn.britannica.com/39/193239-131-181E3553/Statue-Nostradamus.jpg?w=200&h=200&c=crop" alt="Statue of Nostradamus" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/nostradamus-and-his-prophecies" >Nostradamus and His Prophecies</a> </div> </div> </div> </div> </div> </div> <button class="drawerToggle btn position-sticky border btn-xs btn-white btn-circle rounded-sm d-none d-lg-flex " type="button" aria-label="Toggle Drawer"> <em class="material-icons font-18 text-blue" data-icon="keyboard_arrow_left"></em> </button> </div> </div> <div class="col"> <div class="h-100 ml-0 pr-lg-0 "> <div class="h-100 grid gx-0 gx-lg-20"> <div class="h-100 col-sm"> <div class="h-100 infinite-pagination-container d-flex flex-column position-relative"> <div class="position-absolute top-0 h-100 w-100"> <div class="toc-sticky-header d-none d-lg-none bg-gray-50 px-10 px-sm-30 position-sticky w-100 "> <div class="toc-sticky-header-inner-container align-items-center d-flex mx-auto h-100 w-100"> <button class="d-flex d-lg-none btn btn-sm btn-white text-blue border-2 border-gray-100 gtm-mobile-toc-header-button js-sections-button d-lg-none p-10"> <em class="material-icons my-n5 md-icon" data-icon="toc"></em> Contents </button> <div class="header-ai-simplify-button-placeholder"></div> <div class="header-ai-ask-button-placeholder"></div> </div> </div> </div> <div class="grey-box w-100 grey-box-top"> <div class="grey-box-content mx-auto w-100"> <script type="application/ld+json"> { "@context" : "https://schema.org", "@type" : "BreadcrumbList", "itemListElement" : [ { "@type" : "ListItem", "position" : 1, "item" : { "@id" : "https://www.britannica.com/browse/Technology", "name": "Technology" } } , { "@type" : "ListItem", "position" : 2, "item" : { "@id" : "https://www.britannica.com/browse/Web-Communication", "name": "The Web & Communication" } } ] } </script> <nav class="breadcrumb mt-20"> <span class="breadcrumb-item "> <a class="link-gray-600" href="/browse/Technology">Technology</a> </span> <span class="breadcrumb-item "> <a class="link-gray-600" href="/browse/Web-Communication">The Web & Communication</a> </span> </nav> <div class="page2ref-true topic-content topic-type-REGULAR" data-student-article="false"> <script class="page-description-json" type="application/json"> { "url": "/technology/television-technology", "shareUrl": "https://www.britannica.com/technology/television-technology", "browserTitle": "Television | History, Components, & Uses", "firstTopicPage": true, "topicId":1262241 } </script> <div class="reading-channel"> <div class="desktop-header-image module-spacing"> <figure class="md-assembly m-0 mb-20 mb-md-0 card card-borderless print-false" data-assembly-id="13684" data-asm-type="image"> <div class="md-assembly-wrapper card-media " data-type="image"> <a style="min-height: 160px;" href="https://cdn.britannica.com/97/6897-050-FF2A9614/electron-guns-color-television-picture-tube-right.jpg" class="gtm-assembly-link position-relative d-flex align-items-center justify-content-center media-overlay-link card-media" data-href="/media/1/1262241/788"> <picture> <source media="(min-width: 680px)" srcset="https://cdn.britannica.com/97/6897-050-FF2A9614/electron-guns-color-television-picture-tube-right.jpg?w=300"> <img src="https://cdn.britannica.com/97/6897-050-FF2A9614/electron-guns-color-television-picture-tube-right.jpg?w=400&h=300&c=crop" alt="colour television picture tube" loading="eager" /> </picture> <button class="magnifying-glass btn btn-circle position-absolute shadow btn-white top-10 right-10" aria-label="Zoom in"> <em class="material-icons link-blue" data-icon="zoom_in"></em> </button> </a> </div> <figcaption class="card-body"> <div class="md-assembly-caption text-muted font-14 font-serif line-clamp"> <span> <a class="gtm-assembly-link md-assembly-title font-weight-bold d-inline font-sans-serif mr-5 media-overlay-link" href="https://cdn.britannica.com/97/6897-050-FF2A9614/electron-guns-color-television-picture-tube-right.jpg" data-href="/media/1/1262241/788">colour television picture tube</a> <span><span> At right are the electron guns, which generate beams corresponding to the values of red, green, and blue light in the televised image. At left is the aperture grille, through which the beams are focused on the phosphor coating of the screen, forming tiny spots of red, green, and blue that appear to the eye as a single colour. The beam is directed line by line across and down the screen by deflection coils at the neck of the picture tube. </span></span> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-white js-content" aria-label="Toggle more/less fact data"> <span class="link-blue">(more)</span> </button> </span> </div> </figcaption> </figure> </div><div class="topic-header"> <div class="d-flex align-items-top justify-content-between"> <div class="d-flex flex-column"> <div> <div> <h1>television</h1></div> </div> </div> </div> <div class="d-none d-sm-flex flex-row"> <div class="mr-10 mb-15"> <button class="ai-ask-button btn btn-sm border-2 btn-outline-red-400 border-red-400 btn-sm btn-outline-red-400 border-red-400 px-sm-5 px-md-10 js-inline-ai-ask-button"> Ask the Chatbot a Question </button> </div> <div class="d-block md-topic-tools qa-action-buttons mb-15" data-topic-id="1262241"> <button class="js-tooltip btn btn-sm btn-outline-blue border pr-10 border-2 text-nowrap" > <em class="material-icons md-icon ml-n10 my-n5 mr-5" data-icon="more_vert"></em> More Actions </button> <div class="md-more-popover popover popover-sm p-0 font-14 z-1"> <div> <button class="js-print-modal-button js-modal gtm-topic-tool btn btn-sm btn-link gtm-topic-tool font-weight-bold btn-link" data-modal="[data-topic-id=1262241] .md-print-modal" > <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="print"></em> Print </button> <div class="md-print-modal size-lg d-none"> <div class="md-modal-body"> <div class="h2 font-serif d-flex align-items-center pb-15 border-bottom"> <em class="material-icons text-blue mr-10">print</em> Print </div> <div class="mt-20 mb-10"> Please select which sections you would like to print: </div> <form action="/print/article/1262241" method="post" target="_blank" rel="noopener"> <div class="print-box-items"> <ul class="list-unstyled"> <li><label><input class="mr-10" type="checkbox" name="sequence[]" value="0">Table Of Contents</label></li> </ul> </div> <input type="submit" class="btn btn-blue md-disabled" value="Print" /> </form> </div> </div> </div> <div> <button class="js-modal qa-cite-modal-button btn btn-sm btn-link gtm-topic-tool font-weight-bold btn-link" data-modal="[data-topic-id=1262241] .md-cite-modal"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="verified"></em> Cite </button> <div class="md-cite-modal size-lg d-none"> <div class="md-modal-body"> <div class="h2 font-serif d-flex align-items-center pb-15 border-bottom mb-15"> <em class="material-icons text-blue mr-10">verified</em>Cite </div> <div class="font-serif"> While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions. </div> <div class="label mt-20 mb-10">Select Citation Style</div> <select class="js-citation-format-select form-select"> <option selected value="mla">MLA</option> <option value="apa">APA</option> <option value="chicago">Chicago Manual of Style</option> </select> <div class="citation font-serif border rounded p-15 mt-20" data-authors="Fisher, David E., Fisher, Marshall Jon, Noll, A. Michael, Fink, Donald G." data-authors-initial="Fisher, D.E., Fisher, M.J., Noll, A.M., Fink, D.G." data-title="television" data-published-date="21 Jan. 2025" data-url="https://www.britannica.com/technology/television-technology" > <div class="citation-text"></div> </div> <button class="js-copy-citation-button mt-20 btn btn-xs btn-outline-blue border shadow-sm pr-10" > <em class="material-icons md-icon ml-n10 my-n5 mr-5" data-icon="file_copy"></em> <span class="js-citation-status-text">Copy Citation</span> </button> </div> </div> </div> <div> <button class="js-share-modal-button js-modal btn btn-sm btn-link gtm-topic-tool font-weight-bold btn-link" data-modal="[data-topic-id=1262241] .md-share-modal"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="share"></em> Share </button> <div class="md-share-modal size-lg d-none qa-share-modal"> <div class="md-modal-body"> <div class="h2 font-serif d-flex align-items-center pb-15 border-bottom"> <em class="material-icons text-blue mr-10" data-icon="share"></em> Share </div> <div class="label my-20">Share to social media</div> <div class="md-social-toolbar-circle d-flex align-items-start inverted" data-value="share" title="television" data-url="https://www.britannica.com/technology/television-technology" > <a class="social-icon facebook justify-content-center d-flex align-items-center align-self-center" data-provider="facebook" href="https://www.facebook.com/BRITANNICA/" target="_blank" rel="noopener"><span>Facebook</span></a> <a class="social-icon x justify-content-center d-flex align-items-center align-self-center" data-provider="x" href="https://x.com/britannica" target="_blank" rel="noopener"><span>X</span></a> </div> <div class="label pt-20 mt-20 mb-5 border-top">URL</div> <a class="font-serif text-truncate d-inline-block" href="https://www.britannica.com/technology/television-technology">https://www.britannica.com/technology/television-technology</a> </div> </div> </div> <div> <button class="js-feedback-modal-button js-modal btn btn-sm btn-link gtm-topic-tool font-weight-bold btn-link" data-modal=".md-feedback-modal"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="message"></em> Feedback </button> </div> <div> <button class="qa-external-website-modal-button js-modal btn btn-sm btn-link gtm-topic-tool font-weight-bold btn-link" data-modal="[data-topic-id=1262241] .md-websites-modal"> <em class="material-icons md-icon ml-n10 mr-5" data-icon="link"></em> External Websites </button> </div> </div> <div class="md-feedback-modal size-lg d-none"> <div class="md-modal-body"> <div class="h2 font-serif pb-15 border-bottom"> Feedback </div> <form method="post" action="/submission/feedback/1262241"> <div class="my-20"> Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login). </div> <div class="type-menu"> <label for="feedback-type" class="label mb-10">Feedback Type</label> <select id="feedback-type" class="form-select mb-30" name="feedbackTypeId" required> <option value="" selected="selected">Select a type (Required)</option> <option value="1">Factual Correction</option> <option value="2">Spelling/Grammar Correction</option> <option value="3">Link Correction</option> <option value="4">Additional Information</option> <option value="5">Other</option> </select> </div> <label for="feedback" class="label mb-10">Your Feedback</label> <textarea id="feedback" class="form-control mb-30" name="feedback" maxlength="3000" rows="7" required></textarea> <button class="btn btn-blue" type="submit">Submit Feedback</button> </form> <div class="success-messaging d-none mt-30"> <div class="title">Thank you for your feedback</div> <p>Our editors will review what you’ve submitted and determine whether to revise the article.</p> </div> </div> </div> <div class="md-websites-modal size-lg d-none"> <div class="md-modal-body"> <div class="h2 font-serif pb-15 border-bottom font-weight-bold"> External Websites </div> <div class="pb-20"> <ul class="list-unstyled mt-20 lh-lg"> <li><a class="external" href="http://www.factmonster.com/ce6/sci/A0861471.html" target="_blank" rel="noopener nofollow">Fact Monster - Science - Television Technology</a></li> <li><a class="external" href="https://business.columbia.edu/sites/default/files-efs/imce-uploads/CITI/Articles/978-1-4615-4971-0_1.pdf" target="_blank" rel="noopener ">Columbia Business School - The Evolution of Television Technology</a></li> </ul> </div> <div class="md-websites-ebk-title">Britannica Websites</div> <div class="md-websites-ebk-subtitle">Articles from Britannica Encyclopedias for elementary and high school students.</div> <ul class="list-unstyled bps-topic-web-sites lh-lg"> <li><a class="external" href="https://kids.britannica.com/kids/article/television/353844" target="_blank" rel="noopener">television - Children's Encyclopedia (Ages 8-11)</a></li> <li><a class="external" href="https://kids.britannica.com/students/article/television/277292" target="_blank" rel="noopener">television - Student Encyclopedia (Ages 11 and up)</a></li> </ul> </div> </div> </div> </div> <div class="toc-header-marker"></div> <button class="ai-ask-button btn btn-sm border-2 btn-outline-red-400 border-red-400 d-none mr-0 mr-lg-10 ml-5 ml-sm-10 ml-lg-0 p-10 px-sm-5 px-md-10 js-header-ai-ask-button"> Ask the Chatbot a Question </button> <div class="md-byline module-spacing "> <div class="font-serif font-12"> <span class="written-by text-gray-700"> Written by </span> <div class="editor-popover popover p-0"> <a class="d-block p-20 qa-editor-popup gtm-byline font-12 byline-contributor" href="/contributor/David-E-Fisher/5439" > <div class="editor-title font-16 font-weight-bold">David E. Fisher</div> <div class="editor-description font-12 font-serif mt-5 clamp-description text-black">Professor of Geology, the University of Miami, Florida, U.S. Co-author of <i>Tube: The Invention of Television.</i></div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link gtm-byline font-12 byline-contributor text-decoration-underline"> David E. Fisher</span>, <div class="editor-popover popover p-0"> <a class="d-block p-20 qa-editor-popup gtm-byline font-12 byline-contributor" href="/contributor/Marshall-Jon-Fisher/5440" > <div class="editor-title font-16 font-weight-bold">Marshall Jon Fisher</div> <div class="editor-description font-12 font-serif mt-5 clamp-description text-black">Free-lance writer. Co-author of <i>Tube: The Invention of Television.</i></div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link gtm-byline font-12 byline-contributor text-decoration-underline"> Marshall Jon Fisher</span><span class="text-gray-700 mx-5">•</span><a class="see-all border-gray-700 gtm-byline" rel="nofollow" href="https://www.britannica.com/technology/television-technology/additional-info#contributors">All</a> </div> <div class="font-serif font-12 text-gray-700"> <span class="qa-fact-checked-by">Fact-checked by</span> <div class="editor-popover popover p-0"> <a class="d-block p-20 qa-editor-popup font-12" href="/editor/The-Editors-of-Encyclopaedia-Britannica/4419" > <div class="editor-title font-16 font-weight-bold">The Editors of Encyclopaedia Britannica</div> <div class="editor-description font-12 font-serif mt-5 text-black">Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors.</div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link font-12 "> The Editors of Encyclopaedia Britannica</span></div> <div class="last-updated font-12 font-serif"> <span class="text-gray-700"> Last Updated: <time datetime="2025-01-21T00:00:00CST" >Jan 21, 2025</time> •</span> <a class="byline-edit-history" href="https://www.britannica.com/technology/television-technology/additional-info#history" rel="nofollow">Article History</a> </div></div> </div> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button d-none d-sm-block js-sections-inline-button module-spacing btn d-lg-none"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <div class="d-flex d-sm-none flex-row"> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button js-sections-inline-button module-spacing"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <button class="ai-ask-button btn btn-sm border-2 btn-outline-red-400 border-red-400 module-spacing js-inline-ai-ask-button p-10 ml-5"> Ask the Chatbot </button> </div> <div class="js-qf-module qf-module px-40 px-sm-20 py-15 mx-auto module-spacing font-14 bg-gray-50 rounded"> <div class="facts-list mt-10"> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Related Topics: </dt> <dd><a href="/technology/cable-television" topicid="87642">cable television</a></dd> <dd><a href="/technology/HDTV" topicid="265176">HDTV</a></dd> <dd><a href="/technology/V-chip" topicid="1489772">V-chip</a></dd> <dd><a href="/technology/electronic-television-system" topicid="2126401">electronic television system</a></dd> <dd><a href="/technology/mechanical-television-system" topicid="2126406">mechanical television system</a></dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> <div class="text-center"> <a class="btn btn-sm btn-link p-0" href="/facts/television-technology"> See all related content </a> </div> </div> </div> </div><span class="marker before-article"></span><section data-level="1" id="ref1"><span class="marker PREMOD1 mod-inline"></span><p class="topic-paragraph"><strong><span id="ref463773"></span>television (TV)</strong>, a form of <a href="https://www.britannica.com/topic/mass-media" class="md-crosslink " data-show-preview="true">mass media</a> based on the <span id="ref211680"></span><a href="https://www.britannica.com/technology/electronics" class="md-crosslink " data-show-preview="true">electronic</a> delivery of moving images and sound from a source to a <a href="https://www.britannica.com/technology/receiver" class="md-crosslink autoxref " data-show-preview="true">receiver</a>. By extending the senses of <span id="ref211681"></span><a href="https://www.britannica.com/science/vision-physiology" class="md-crosslink " data-show-preview="true">vision</a> and hearing beyond the limits of physical distance, television has had a considerable influence on society. <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="Conceived" href="https://www.britannica.com/dictionary/Conceived" data-type="EB">Conceived</a> in the early 20th century as a possible medium for education and interpersonal <a href="https://www.britannica.com/topic/communication" class="md-crosslink autoxref " data-show-preview="true">communication</a>, it became by mid-century a vibrant broadcast medium, using the model of broadcast <a href="https://www.britannica.com/topic/radio" class="md-crosslink " data-show-preview="true">radio</a> to bring news and entertainment to people all over the world. Television is now delivered in a variety of ways: “over the air” by terrestrial <a href="https://www.britannica.com/science/radio-wave" class="md-crosslink " data-show-preview="true">radio waves</a> (traditional broadcast TV); along <a href="https://www.britannica.com/technology/coaxial-cable" class="md-crosslink " data-show-preview="true">coaxial cables</a> (cable TV); reflected off of <a href="https://www.britannica.com/technology/communications-satellite" class="md-crosslink " data-show-preview="true">satellites</a> held in geostationary <a href="https://www.britannica.com/place/Earth" class="md-crosslink " data-show-preview="true">Earth</a> orbit (direct broadcast satellite, or DBS, TV); streamed through the Internet; and recorded optically on digital video discs (<a href="https://www.britannica.com/technology/DVD" class="md-crosslink " data-show-preview="true">DVDs</a>) and <a href="https://www.britannica.com/technology/Blu-ray" class="md-crosslink " data-show-preview="true">Blu-ray</a> discs.</p><span class="marker MOD1 mod-inline"></span><span class="marker PREMOD2 mod-inline"></span><p class="topic-paragraph">The technical standards for modern television, both monochrome (black-and-white) and <a href="https://www.britannica.com/science/color" class="md-crosslink autoxref " data-show-preview="true">colour</a>, were first established in the middle of the 20th century. Improvements have been made continuously since that time, and television <a href="https://www.britannica.com/technology/technology" class="md-crosslink autoxref " data-show-preview="true">technology</a> changed considerably in the early 21st century. Much attention was focused on increasing the picture resolution (high-definition television [HDTV]) and on changing the <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="dimensions" href="https://www.britannica.com/dictionary/dimensions" data-type="EB">dimensions</a> of the television receiver to show wide-screen pictures. In addition, the transmission of digitally encoded television signals was instituted to provide interactive service and to broadcast multiple programs in the channel space previously occupied by one program.</p><span class="marker MOD2 mod-inline"></span><span class="marker PREMOD3 mod-inline"></span><p class="topic-paragraph">Despite this continuous technical evolution, modern television is best understood first by learning the history and principles of monochrome television and then by extending that learning to colour. The emphasis of this article, therefore, is on first principles and major developments—basic knowledge that is needed to understand and appreciate future technological developments and enhancements. Because American TV programs, like American popular <a href="https://www.britannica.com/topic/culture" class="md-crosslink " data-show-preview="true">culture</a> in general in the 20th and early 21st centuries, have spread far beyond the boundaries of the United States and have had a <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="pervasive" href="https://www.merriam-webster.com/dictionary/pervasive" data-type="MW">pervasive</a> influence on global popular <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="culture" href="https://www.merriam-webster.com/dictionary/culture" data-type="MW">culture</a>, see also "<a href="https://www.britannica.com/art/television-in-the-United-States" class="md-crosslink " data-show-preview="true">television in the United States</a>," which deals with the history and development of TV programs.</p><span class="marker MOD3 mod-inline"></span></section> <span class="md-signature font-12"><a href="/contributor/A-Michael-Noll/5434">A. Michael Noll</a></span> <span class="marker h2"></span><section data-level="1" id="ref25145"> <h2 class="h1">The development of television systems</h2> <section data-level="2" id="ref25146"> <h2 class="h2"><span id="ref1257623"></span>Mechanical systems</h2> <span class="marker PREMOD4 mod-inline"></span><p class="topic-paragraph">The dream of seeing distant places is as old as the human imagination. Priests in ancient Greece studied the entrails of birds, trying to see in them what the birds had seen when they flew over the horizon. They believed that their gods, sitting in comfort on <a href="https://www.britannica.com/place/Mount-Olympus-mountain-Greece" class="md-crosslink autoxref " data-show-preview="true">Mount Olympus</a>, were gifted with the ability to watch human activity all over the world. And the opening scene of <a href="https://www.britannica.com/biography/William-Shakespeare" class="md-crosslink autoxref " data-show-preview="true">William Shakespeare’s</a> play <em>Henry IV, Part 1</em> introduces the character Rumour, upon whom the other characters rely for news of what is happening in the far corners of England.</p><span class="marker MOD4 mod-inline"></span> <span class="marker PREMOD5 mod-inline"></span><p class="topic-paragraph">For ages it remained a dream, and then television came along, beginning with an accidental discovery. In 1872, while investigating materials for use in the transatlantic cable, English <a href="https://www.britannica.com/technology/telegraph" class="md-crosslink autoxref " data-show-preview="true">telegraph</a> worker Joseph May realized that a <span id="ref211682"></span><a href="https://www.britannica.com/science/selenium" class="md-crosslink " data-show-preview="true">selenium</a> wire was varying in its electrical conductivity. Further investigation showed that the change occurred when a beam of sunlight fell on the wire, which by chance had been placed on a table near the window. Although its importance was not realized at the time, this happenstance provided the basis for changing light into an electric signal.</p><div class="module-spacing"> </div><span class="marker MOD5 mod-inline"></span> <span class="marker PREMOD6 mod-inline"></span><p class="topic-paragraph">In 1880 a French engineer, Maurice LeBlanc, published an article in the journal <em>La Lumière électrique</em> that formed the basis of all subsequent television. LeBlanc proposed a scanning mechanism that would take advantage of the <a href="https://www.britannica.com/science/retina" class="md-crosslink autoxref " data-show-preview="true">retina’s</a> temporary but finite retainment of a visual image. He <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="envisaged" href="https://www.merriam-webster.com/dictionary/envisaged" data-type="MW">envisaged</a> a <span id="ref211684"></span><a href="https://www.britannica.com/technology/photoelectric-cell" class="md-crosslink " data-show-preview="true">photoelectric cell</a> that would look upon only one portion at a time of the picture to be transmitted. Starting at the upper left corner of the picture, the cell would proceed to the right-hand side and then jump back to the left-hand side, only one line lower. It would continue in this way, transmitting information on how much light was seen at each portion, until the entire picture was scanned, in a manner similar to the eye reading a page of text. A receiver would be synchronized with the transmitter, reconstructing the original image line by line.</p><span class="marker MOD6 mod-inline"></span> <span class="marker PREMOD7 mod-inline"></span><p class="topic-paragraph">The <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="concept" href="https://www.britannica.com/dictionary/concept" data-type="EB">concept</a> of scanning, which established the possibility of using only a single wire or channel for transmission of an entire image, became and remains to this day the basis of all television. LeBlanc, however, was never able to construct a working machine. Nor was the man who took television to the next stage: <a href="https://www.britannica.com/biography/Paul-Gottlieb-Nipkow" class="md-crosslink " data-show-preview="true">Paul Nipkow</a>, a German engineer who invented the scanning disk. Nipkow’s 1884 patent for an <em>Elektrisches Telescop</em> was based on a simple rotating disk perforated with an inward-spiraling sequence of holes. It would be placed so that it blocked reflected light from the subject. As the disk rotated, the outermost hole would move across the scene, letting through light from the first “line” of the picture. The next hole would do the same thing slightly lower, and so on. One complete revolution of the disk would provide a complete picture, or “scan,” of the subject.</p><div class="module-spacing"> <DIV class="marketing-INLINE_SUBSCRIPTION marketing-content" data-marketing-id="INLINE_SUBSCRIPTION"><style> .student-promo-banner-wrapper { container-type: inline-size; margin-bottom: 15px; } @container (min-width: 475px) { .student-promo-banner { flex-direction: row; } .student-promo-banner-img-wrapper { margin-bottom: 0; margin-right: 10px; justify-content: flex-start; } .student-promo-banner-text-wrapper { text-align: left; margin-bottom: 0px; margin-left: 10px; } .student-promo-banner-button-wrapper { margin-right: 0; } }</style> <div class="student-promo-banner-wrapper"> <div class="student-promo-banner d-flex flex-column align-items-center bg-blue rounded p-20"> <div class="student-promo-banner-img-wrapper mb-20 mr-0 d-flex justify-content-center"> <img class="rounded" style="max-width: 100px; min-width: 80px" src="https://cdn.britannica.com/marketing/BlueThistle.webp" /> </div> <div class="student-promo-banner-text-wrapper ml-0 mb-10 text-center text-white"> <div class="h2 mb-10">Get Unlimited Access</div> <div class="h4 font-weight-semi-bold">Try Britannica Premium for free and discover more.</div> </div> <div class="student-promo-banner-button-wrapper d-flex justify-content-center align-items-center ml-auto mr-auto"> <a class="btn btn-m btn-orange" href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=inline-cta&utm_campaign=august-2024">Subscribe</a> </div> </div> </div> </DIV></div><span class="marker MOD7 mod-inline"></span> <span class="marker PREMOD8 mod-inline"></span><div class="assemblies"><div class="w-100"><figure class="md-assembly m-0 mb-md-0 card card-borderless print-false" data-assembly-id="60151" data-asm-type="image"><div class="md-assembly-wrapper card-media" data-type="image"><a href="https://cdn.britannica.com/15/70015-004-007D6A99/John-Logie-Baird-Stookie-Bill-television-transmitter.jpg" class="gtm-assembly-link position-relative d-flex align-items-center justify-content-center media-overlay-link card-media" data-href="/media/1/1262241/60151"><picture><source media="(min-width: 680px)" srcset="https://cdn.britannica.com/15/70015-004-007D6A99/John-Logie-Baird-Stookie-Bill-television-transmitter.jpg?w=300"><img src="https://cdn.britannica.com/15/70015-004-007D6A99/John-Logie-Baird-Stookie-Bill-television-transmitter.jpg?w=300" alt="John Logie Baird with television transmitter" data-width="444" data-height="300" loading="eager"></picture><button class="magnifying-glass btn btn-circle position-absolute shadow btn-white top-10 right-10" aria-label="Zoom in"><em class="material-icons link-blue" data-icon="zoom_in"></em></button></a></div><figcaption class="card-body"><div class="md-assembly-caption text-muted font-14 font-serif line-clamp"><span><a class="gtm-assembly-link md-assembly-title font-weight-bold d-inline font-sans-serif mr-5 media-overlay-link" href="https://cdn.britannica.com/15/70015-004-007D6A99/John-Logie-Baird-Stookie-Bill-television-transmitter.jpg" data-href="/media/1/1262241/60151">John Logie Baird with television transmitter</a><span>John Logie Baird standing next to his television transmitter of 1925–26. To Baird's left in the case is “Stookie Bill,” a ventriloquist's dummy that was scanned by the spinning Nipkow disk in order to produce a picture signal.</span><button class="js-more-btn d-none btn btn-unstyled font-12 bg-white js-content" aria-label="Toggle more/less fact data"><span class="link-blue">(more)</span></button></span></div></figcaption></figure></div></div><p class="topic-paragraph">This concept was eventually used by <span id="ref287209"></span><a href="https://www.britannica.com/biography/John-Logie-Baird" class="md-crosslink " data-show-preview="true">John Logie Baird</a> in <span id="ref827577"></span><a href="https://www.britannica.com/topic/history-of-United-Kingdom" class="md-crosslink ">Britain</a> (<em>see</em> the <span class="link-blue media-overlay-link asmref" data-href="/media/1/1262241/60151">photograph</span>) and <span id="ref827575"></span>Charles Francis Jenkins in the <span id="ref827574"></span><a href="https://www.britannica.com/topic/history-of-United-States" class="md-crosslink ">United States</a> to build the world’s first successful televisions. The question of priority depends on one’s definition of television. In 1922 Jenkins sent a still picture by radio waves, but the first true television success, the transmission of a live human face, was achieved by Baird in 1925. (The word <em>television</em> itself had been coined by a Frenchman, Constantin Perskyi, at the 1900 <a href="https://www.britannica.com/place/Paris" class="md-crosslink autoxref " data-show-preview="true">Paris</a> Exhibition.)</p><span class="marker MOD8 mod-inline"></span> <span class="marker PREMOD9 mod-inline"></span><p class="topic-paragraph">The efforts of Jenkins and Baird were generally greeted with ridicule or <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="apathy" href="https://www.merriam-webster.com/dictionary/apathy" data-type="MW">apathy</a>. As far back as 1880 an article in the British journal <em>Nature</em> had speculated that television was possible but not worthwhile: the cost of building a system would not be repaid, for there was no way to make money out of it. A later article in <em>Scientific American</em> thought there might be some uses for television, but entertainment was not one of them. Most people thought the concept was lunacy.</p><span class="marker MOD9 mod-inline"></span> <span class="marker PREMOD10 mod-inline"></span><p class="topic-paragraph">Nevertheless, the work went on and began to produce results and competitors. In 1927 the American Telephone and Telegraph Company (<a href="https://www.britannica.com/money/ATandT-Corporation" class="md-crosslink " data-show-preview="true">AT&T</a>) gave a public demonstration of the new technology, and by 1928 the <a href="https://www.britannica.com/money/General-Electric" class="md-crosslink " data-show-preview="true">General Electric Company</a> (GE) had begun regular television broadcasts. GE used a system designed by <a href="https://www.britannica.com/biography/Ernst-F-W-Alexanderson" class="md-crosslink " data-show-preview="true">Ernst F.W. Alexanderson</a> that offered “the <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="amateur" href="https://www.britannica.com/dictionary/amateur" data-type="EB">amateur</a>, provided with such receivers as he may design or acquire, an opportunity to pick up the signals,” which were generally of smoke rising from a chimney or other such interesting subjects. That same year Jenkins began to sell television kits by mail and established his own television station, showing cartoon pantomime programs. In 1929 Baird convinced the <span id="ref287214"></span><a href="https://www.britannica.com/money/British-Broadcasting-Corporation" class="md-crosslink " data-show-preview="true">British Broadcasting Corporation</a> (BBC) to allow him to produce half-hour shows at midnight three times a week. The following years saw the first “television boom,” with thousands of viewers buying or constructing primitive sets to watch primitive programs.</p><div class="one-good-fact-module"> </div><span class="marker MOD10 mod-inline"></span> <span class="marker PREMOD11 mod-inline"></span><p class="topic-paragraph">Not everyone was entranced. C.P. Scott, editor of the <em>Manchester Guardian</em>, warned: “Television? The word is half Greek and half Latin. No good will come of it.” More important, the lure of a new technology soon paled. The pictures, formed of only 30 lines repeating approximately 12 times per second, flickered badly on dim receiver screens only a few inches high. Programs were simple, repetitive, and ultimately <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="boring" href="https://www.britannica.com/dictionary/boring" data-type="EB">boring</a>. Nevertheless, even while the boom collapsed a competing development was taking place in the realm of the electron.</p><span class="marker MOD11 mod-inline"></span> </section> </section><span class="marker end-of-content"></span><span class="marker after-article"></span></div> <div id="chatbot-simplify-root"></div> <div id="chatbot-root"></div> </div> </div> </div> <div class="ai-dialog-placeholder"></div> </div> </div> <aside class="col-md-da-320"></aside> </div> </div> </div> </div> </article> </div> </div> </div> </div> </main> <div id="md-footer"></div> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>  <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"Topic","templateName":"DESKTOP","pageNumber":1,"pagesTotal":21,"pageId":1262241,"pageLength":1270,"initialLoad":true,"lastPageOfScroll":false} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-133/js/libs/jquery-3.5.0.min.js?v=3.133.48"></script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-133/dist/topic-page.js?v=3.133.48' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"B","adLeg":"B","userType":"ANONYMOUS","pageType":"Topic","pageSubtype":null,"articleTemplateType":"PAGINATED","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":true,"hasAiTopQuestions":false,"hasSimplifyButton":false} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>

CINXE.COM

Television | History, Components, & Uses | Britannica