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cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Aspetto</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="//donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_it.wikipedia.org&uselang=it" class=""><span>Fai una donazione</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Speciale:CreaUtenza&returnto=Lumen" title="Si consiglia di registrarsi e di effettuare l'accesso, anche se non è obbligatorio" class=""><span>registrati</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Speciale:Entra&returnto=Lumen" title="Si consiglia di effettuare l'accesso, anche se non è obbligatorio [o]" accesskey="o" class=""><span>entra</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Altre 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class="vector-menu-heading"> Pagine per utenti anonimi <a href="/wiki/Aiuto:Benvenuto" aria-label="Ulteriori informazioni sulla contribuzione"><span>ulteriori informazioni</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Speciale:MieiContributi" title="Un elenco delle modifiche fatte da questo indirizzo IP [y]" accesskey="y"><span>contributi</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Speciale:MieDiscussioni" title="Discussioni sulle modifiche fatte da questo indirizzo IP [n]" accesskey="n"><span>discussioni</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Sito"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Indice" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Indice</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">sposta nella barra laterale</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">nascondi</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">Inizio</div> </a> </li> <li id="toc-Differenza_tra_lux_e_lumen" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Differenza_tra_lux_e_lumen"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Differenza tra lux e lumen</span> </div> </a> <ul id="toc-Differenza_tra_lux_e_lumen-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Note" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Note"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Note</span> </div> </a> <ul id="toc-Note-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Voci_correlate" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Voci_correlate"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Voci correlate</span> </div> </a> <ul id="toc-Voci_correlate-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Altri_progetti" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Altri_progetti"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Altri progetti</span> </div> </a> <ul id="toc-Altri_progetti-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Collegamenti_esterni" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Collegamenti_esterni"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Collegamenti esterni</span> </div> </a> <ul id="toc-Collegamenti_esterni-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Indice" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Mostra/Nascondi l'indice" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Mostra/Nascondi l'indice</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Lumen</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Vai a una voce in un'altra lingua. Disponibile in 69 lingue" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-69" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">69 lingue</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%84%D9%88%D9%85%D9%86" title="لومن - arabo" lang="ar" hreflang="ar" data-title="لومن" data-language-autonym="العربية" data-language-local-name="arabo" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Lumen" title="Lumen - asturiano" lang="ast" hreflang="ast" data-title="Lumen" data-language-autonym="Asturianu" data-language-local-name="asturiano" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%9B%D1%8E%D0%BC%D0%B5%D0%BD" title="Люмен - bielorusso" lang="be" hreflang="be" data-title="Люмен" data-language-autonym="Беларуская" data-language-local-name="bielorusso" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%9B%D1%8E%D0%BC%D1%8D%D0%BD" title="Люмэн - Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Люмэн" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9B%D1%83%D0%BC%D0%B5%D0%BD" title="Лумен - bulgaro" lang="bg" hreflang="bg" data-title="Лумен" data-language-autonym="Български" data-language-local-name="bulgaro" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%B2%E0%A7%81%E0%A6%AE%E0%A7%87%E0%A6%A8" title="লুমেন - bengalese" lang="bn" hreflang="bn" data-title="লুমেন" data-language-autonym="বাংলা" data-language-local-name="bengalese" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-bo mw-list-item"><a href="https://bo.wikipedia.org/wiki/%E0%BD%A3%E0%BD%B4%E0%BC%8B%E0%BD%98%E0%BD%BA%E0%BD%93%E0%BC%8D" title="ལུ་མེན། - tibetano" lang="bo" hreflang="bo" data-title="ལུ་མེན།" data-language-autonym="བོད་ཡིག" data-language-local-name="tibetano" class="interlanguage-link-target"><span>བོད་ཡིག</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Lumen_(jedinica)" title="Lumen (jedinica) - bosniaco" lang="bs" hreflang="bs" data-title="Lumen (jedinica)" data-language-autonym="Bosanski" data-language-local-name="bosniaco" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Lumen" title="Lumen - catalano" lang="ca" hreflang="ca" data-title="Lumen" data-language-autonym="Català" data-language-local-name="catalano" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Lumen" title="Lumen - ceco" lang="cs" hreflang="cs" data-title="Lumen" data-language-autonym="Čeština" data-language-local-name="ceco" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%9B%D1%8E%D0%BC%D0%B5%D0%BD" title="Люмен - ciuvascio" lang="cv" hreflang="cv" data-title="Люмен" data-language-autonym="Чӑвашла" data-language-local-name="ciuvascio" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Lumen" title="Lumen - danese" lang="da" hreflang="da" data-title="Lumen" data-language-autonym="Dansk" data-language-local-name="danese" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Lumen_(Einheit)" title="Lumen (Einheit) - tedesco" lang="de" hreflang="de" data-title="Lumen (Einheit)" data-language-autonym="Deutsch" data-language-local-name="tedesco" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%9B%CE%BF%CF%8D%CE%BC%CE%B5%CE%BD_(%CE%BC%CE%BF%CE%BD%CE%AC%CE%B4%CE%B1_%CE%BC%CE%AD%CF%84%CF%81%CE%B7%CF%83%CE%B7%CF%82)" title="Λούμεν (μονάδα μέτρησης) - greco" lang="el" hreflang="el" data-title="Λούμεν (μονάδα μέτρησης)" data-language-autonym="Ελληνικά" data-language-local-name="greco" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-en mw-list-item"><a href="https://en.wikipedia.org/wiki/Lumen_(unit)" title="Lumen (unit) - inglese" lang="en" hreflang="en" data-title="Lumen (unit)" data-language-autonym="English" data-language-local-name="inglese" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Lumeno" title="Lumeno - esperanto" lang="eo" hreflang="eo" data-title="Lumeno" data-language-autonym="Esperanto" data-language-local-name="esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Lumen" title="Lumen - spagnolo" lang="es" hreflang="es" data-title="Lumen" data-language-autonym="Español" data-language-local-name="spagnolo" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Luumen" title="Luumen - estone" lang="et" hreflang="et" data-title="Luumen" data-language-autonym="Eesti" data-language-local-name="estone" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Lumen_(unitatea)" title="Lumen (unitatea) - basco" lang="eu" hreflang="eu" data-title="Lumen (unitatea)" data-language-autonym="Euskara" data-language-local-name="basco" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%84%D9%88%D9%85%D9%86_(%DB%8C%DA%A9%D8%A7)" title="لومن (یکا) - persiano" lang="fa" hreflang="fa" data-title="لومن (یکا)" data-language-autonym="فارسی" data-language-local-name="persiano" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Luumen" title="Luumen - finlandese" lang="fi" hreflang="fi" data-title="Luumen" data-language-autonym="Suomi" data-language-local-name="finlandese" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Lumen_(unit%C3%A9)" title="Lumen (unité) - francese" lang="fr" hreflang="fr" data-title="Lumen (unité)" data-language-autonym="Français" data-language-local-name="francese" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-frr mw-list-item"><a href="https://frr.wikipedia.org/wiki/Lumen" title="Lumen - frisone settentrionale" lang="frr" hreflang="frr" data-title="Lumen" data-language-autonym="Nordfriisk" data-language-local-name="frisone settentrionale" class="interlanguage-link-target"><span>Nordfriisk</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/L%C3%BAman" title="Lúman - irlandese" lang="ga" hreflang="ga" data-title="Lúman" data-language-autonym="Gaeilge" data-language-local-name="irlandese" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Lumen" title="Lumen - galiziano" lang="gl" hreflang="gl" data-title="Lumen" data-language-autonym="Galego" data-language-local-name="galiziano" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%9C%D7%95%D7%9E%D7%9F" title="לומן - ebraico" lang="he" hreflang="he" data-title="לומן" data-language-autonym="עברית" data-language-local-name="ebraico" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Lumen" title="Lumen - croato" lang="hr" hreflang="hr" data-title="Lumen" data-language-autonym="Hrvatski" data-language-local-name="croato" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Lumen_(m%C3%A9rt%C3%A9kegys%C3%A9g)" title="Lumen (mértékegység) - ungherese" lang="hu" hreflang="hu" data-title="Lumen (mértékegység)" data-language-autonym="Magyar" data-language-local-name="ungherese" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D4%BC%D5%B5%D5%B8%D6%82%D5%B4%D5%A5%D5%B6_(%D5%B9%D5%A1%D6%83%D5%B4%D5%A1%D5%B6_%D5%B4%D5%AB%D5%A1%D5%BE%D5%B8%D6%80)" title="Լյումեն (չափման միավոր) - armeno" lang="hy" hreflang="hy" data-title="Լյումեն (չափման միավոր)" data-language-autonym="Հայերեն" data-language-local-name="armeno" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Lumen_(satuan)" title="Lumen (satuan) - indonesiano" lang="id" hreflang="id" data-title="Lumen (satuan)" data-language-autonym="Bahasa Indonesia" data-language-local-name="indonesiano" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-io mw-list-item"><a href="https://io.wikipedia.org/wiki/Lumeno" title="Lumeno - ido" lang="io" hreflang="io" data-title="Lumeno" data-language-autonym="Ido" data-language-local-name="ido" class="interlanguage-link-target"><span>Ido</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/L%C3%BAmen" title="Lúmen - islandese" lang="is" hreflang="is" data-title="Lúmen" data-language-autonym="Íslenska" data-language-local-name="islandese" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%83%AB%E3%83%BC%E3%83%A1%E3%83%B3" title="ルーメン - giapponese" lang="ja" hreflang="ja" data-title="ルーメン" data-language-autonym="日本語" data-language-local-name="giapponese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%9A%E1%83%A3%E1%83%9B%E1%83%94%E1%83%9C%E1%83%98" title="ლუმენი - georgiano" lang="ka" hreflang="ka" data-title="ლუმენი" data-language-autonym="ქართული" data-language-local-name="georgiano" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%9B%D1%8E%D0%BC%D0%B5%D0%BD" title="Люмен - kazako" lang="kk" hreflang="kk" data-title="Люмен" data-language-autonym="Қазақша" data-language-local-name="kazako" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%A3%A8%EB%A9%98" title="루멘 - coreano" lang="ko" hreflang="ko" data-title="루멘" data-language-autonym="한국어" data-language-local-name="coreano" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-ky mw-list-item"><a href="https://ky.wikipedia.org/wiki/%D0%9B%D1%8E%D0%BC%D0%B5%D0%BD" title="Люмен - kirghiso" lang="ky" hreflang="ky" data-title="Люмен" data-language-autonym="Кыргызча" data-language-local-name="kirghiso" class="interlanguage-link-target"><span>Кыргызча</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Liumenas" title="Liumenas - lituano" lang="lt" hreflang="lt" data-title="Liumenas" data-language-autonym="Lietuvių" data-language-local-name="lituano" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/L%C5%ABmens" title="Lūmens - lettone" lang="lv" hreflang="lv" data-title="Lūmens" data-language-autonym="Latviešu" data-language-local-name="lettone" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%9B%D1%83%D0%BC%D0%B5%D0%BD_(%D0%B5%D0%B4%D0%B8%D0%BD%D0%B8%D1%86%D0%B0)" title="Лумен (единица) - macedone" lang="mk" hreflang="mk" data-title="Лумен (единица)" data-language-autonym="Македонски" data-language-local-name="macedone" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%B2%E0%B5%82%E0%B4%AE%E0%B5%86%E0%B5%BB_(%E0%B4%AF%E0%B5%82%E0%B4%A3%E0%B4%BF%E0%B4%B1%E0%B5%8D%E0%B4%B1%E0%B5%8D)" title="ലൂമെൻ (യൂണിറ്റ്) - malayalam" lang="ml" hreflang="ml" data-title="ലൂമെൻ (യൂണിറ്റ്)" data-language-autonym="മലയാളം" data-language-local-name="malayalam" class="interlanguage-link-target"><span>മലയാളം</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Lumen_(unit)" title="Lumen (unit) - malese" lang="ms" hreflang="ms" data-title="Lumen (unit)" data-language-autonym="Bahasa Melayu" data-language-local-name="malese" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Lumen_(eenheid)" title="Lumen (eenheid) - olandese" lang="nl" hreflang="nl" data-title="Lumen (eenheid)" data-language-autonym="Nederlands" data-language-local-name="olandese" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Lumen" title="Lumen - norvegese nynorsk" lang="nn" hreflang="nn" data-title="Lumen" data-language-autonym="Norsk nynorsk" data-language-local-name="norvegese nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Lumen" title="Lumen - norvegese bokmål" lang="nb" hreflang="nb" data-title="Lumen" data-language-autonym="Norsk bokmål" data-language-local-name="norvegese bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Lumen" title="Lumen - polacco" lang="pl" hreflang="pl" data-title="Lumen" data-language-autonym="Polski" data-language-local-name="polacco" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/L%C3%BAmen" title="Lúmen - portoghese" lang="pt" hreflang="pt" data-title="Lúmen" data-language-autonym="Português" data-language-local-name="portoghese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Lumen" title="Lumen - rumeno" lang="ro" hreflang="ro" data-title="Lumen" data-language-autonym="Română" data-language-local-name="rumeno" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9B%D1%8E%D0%BC%D0%B5%D0%BD" title="Люмен - russo" lang="ru" hreflang="ru" data-title="Люмен" data-language-autonym="Русский" data-language-local-name="russo" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-scn mw-list-item"><a href="https://scn.wikipedia.org/wiki/Lumen" title="Lumen - siciliano" lang="scn" hreflang="scn" data-title="Lumen" data-language-autonym="Sicilianu" data-language-local-name="siciliano" class="interlanguage-link-target"><span>Sicilianu</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Lumen" title="Lumen - serbo-croato" lang="sh" hreflang="sh" data-title="Lumen" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="serbo-croato" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Lumen_(unit)" title="Lumen (unit) - Simple English" lang="en-simple" hreflang="en-simple" data-title="Lumen (unit)" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/L%C3%BAmen_(jednotka)" title="Lúmen (jednotka) - slovacco" lang="sk" hreflang="sk" data-title="Lúmen (jednotka)" data-language-autonym="Slovenčina" data-language-local-name="slovacco" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Lumen" title="Lumen - sloveno" lang="sl" hreflang="sl" data-title="Lumen" data-language-autonym="Slovenščina" data-language-local-name="sloveno" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Lumeni" title="Lumeni - albanese" lang="sq" hreflang="sq" data-title="Lumeni" data-language-autonym="Shqip" data-language-local-name="albanese" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9B%D1%83%D0%BC%D0%B5%D0%BD" title="Лумен - serbo" lang="sr" hreflang="sr" data-title="Лумен" data-language-autonym="Српски / srpski" data-language-local-name="serbo" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Lumen_(enhet)" title="Lumen (enhet) - svedese" lang="sv" hreflang="sv" data-title="Lumen (enhet)" data-language-autonym="Svenska" data-language-local-name="svedese" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%B2%E0%AF%82%E0%AE%AE%E0%AE%A9%E0%AF%8D" title="லூமன் - tamil" lang="ta" hreflang="ta" data-title="லூமன்" data-language-autonym="தமிழ்" data-language-local-name="tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-te mw-list-item"><a href="https://te.wikipedia.org/wiki/%E0%B0%B2%E0%B1%8D%E0%B0%AF%E0%B1%82%E0%B0%AE%E0%B1%86%E0%B0%A8%E0%B1%8D" title="ల్యూమెన్ - telugu" lang="te" hreflang="te" data-title="ల్యూమెన్" data-language-autonym="తెలుగు" data-language-local-name="telugu" class="interlanguage-link-target"><span>తెలుగు</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%A5%E0%B8%B9%E0%B9%80%E0%B8%A1%E0%B8%99" title="ลูเมน - thailandese" lang="th" hreflang="th" data-title="ลูเมน" data-language-autonym="ไทย" data-language-local-name="thailandese" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/L%C3%BCmen" title="Lümen - turco" lang="tr" hreflang="tr" data-title="Lümen" data-language-autonym="Türkçe" data-language-local-name="turco" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9B%D1%8E%D0%BC%D0%B5%D0%BD" title="Люмен - ucraino" lang="uk" hreflang="uk" data-title="Люмен" data-language-autonym="Українська" data-language-local-name="ucraino" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%D9%86%D9%88%D8%B1%DB%8C%DB%81_(%D8%A7%DA%A9%D8%A7%D8%A6%DB%8C)" title="نوریہ (اکائی) - urdu" lang="ur" hreflang="ur" data-title="نوریہ (اکائی)" data-language-autonym="اردو" data-language-local-name="urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Lumen_(birlik)" title="Lumen (birlik) - uzbeco" lang="uz" hreflang="uz" data-title="Lumen (birlik)" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="uzbeco" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Lumen_(%C4%91%C6%A1n_v%E1%BB%8B)" title="Lumen (đơn vị) - vietnamita" lang="vi" hreflang="vi" data-title="Lumen (đơn vị)" data-language-autonym="Tiếng Việt" data-language-local-name="vietnamita" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E6%B5%81%E6%98%8E" title="流明 - wu" lang="wuu" hreflang="wuu" data-title="流明" data-language-autonym="吴语" data-language-local-name="wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-xmf mw-list-item"><a href="https://xmf.wikipedia.org/wiki/%E1%83%9A%E1%83%A3%E1%83%9B%E1%83%94%E1%83%9C%E1%83%98" title="ლუმენი - mengrelio" lang="xmf" hreflang="xmf" data-title="ლუმენი" data-language-autonym="მარგალური" data-language-local-name="mengrelio" class="interlanguage-link-target"><span>მარგალური</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E6%B5%81%E6%98%8E" title="流明 - cinese" lang="zh" hreflang="zh" data-title="流明" data-language-autonym="中文" data-language-local-name="cinese" class="interlanguage-link-target"><span>中文</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E6%B5%81%E6%98%8E" title="流明 - cantonese" lang="yue" hreflang="yue" data-title="流明" data-language-autonym="粵語" data-language-local-name="cantonese" class="interlanguage-link-target"><span>粵語</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q484092#sitelinks-wikipedia" title="Modifica collegamenti interlinguistici" class="wbc-editpage">Modifica collegamenti</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespace"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Lumen" title="Vedi la voce [c]" accesskey="c"><span>Voce</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Discussione:Lumen" rel="discussion" title="Vedi le discussioni relative a questa pagina [t]" accesskey="t"><span>Discussione</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" 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title="Modifica questa pagina [v]" accesskey="v"><span>Modifica</span></a></li><li id="ca-more-edit" class="collapsible vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Lumen&action=edit" title="Modifica il wikitesto di questa pagina [e]" accesskey="e"><span>Modifica wikitesto</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Lumen&action=history"><span>Cronologia</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> Generale </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Speciale:PuntanoQui/Lumen" title="Elenco di tutte le pagine che sono collegate a questa [j]" accesskey="j"><span>Puntano qui</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Speciale:ModificheCorrelate/Lumen" rel="nofollow" title="Elenco delle ultime modifiche alle pagine collegate a questa [k]" accesskey="k"><span>Modifiche correlate</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/Speciale:PagineSpeciali" title="Elenco di tutte le pagine speciali [q]" accesskey="q"><span>Pagine speciali</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Lumen&oldid=133722788" title="Collegamento permanente a questa versione di questa pagina"><span>Link permanente</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Lumen&action=info" title="Ulteriori informazioni su questa pagina"><span>Informazioni pagina</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Speciale:Cita&page=Lumen&id=133722788&wpFormIdentifier=titleform" title="Informazioni su come citare questa pagina"><span>Cita questa voce</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Speciale:UrlShortener&url=https%3A%2F%2Fit.wikipedia.org%2Fwiki%2FLumen"><span>Ottieni URL breve</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Speciale:QrCode&url=https%3A%2F%2Fit.wikipedia.org%2Fwiki%2FLumen"><span>Scarica codice QR</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Stampa/esporta </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-create_a_book" class="mw-list-item"><a href="/w/index.php?title=Speciale:Libro&bookcmd=book_creator&referer=Lumen"><span>Crea un libro</span></a></li><li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Speciale:DownloadAsPdf&page=Lumen&action=show-download-screen"><span>Scarica come PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Lumen&printable=yes" title="Versione stampabile di questa pagina [p]" accesskey="p"><span>Versione stampabile</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In altri progetti </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q484092" title="Collegamento all'elemento connesso dell'archivio dati [g]" accesskey="g"><span>Elemento Wikidata</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Strumenti pagine"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Aspetto"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Aspetto</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">sposta nella barra laterale</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">nascondi</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">Da Wikipedia, l'enciclopedia libera.</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="it" dir="ltr"><style data-mw-deduplicate="TemplateStyles:r130658281">body:not(.skin-minerva) .mw-parser-output .hatnote.nota-disambigua{clear:both;margin-top:0;padding:.05em .5em}</style> <style data-mw-deduplicate="TemplateStyles:r139142988">.mw-parser-output .hatnote-content{align-items:center;display:flex}.mw-parser-output .hatnote-icon{flex-shrink:0}.mw-parser-output .hatnote-icon img{display:flex}.mw-parser-output .hatnote-text{font-style:italic}body:not(.skin-minerva) .mw-parser-output .hatnote{border:1px solid #CCC;display:flex;margin:.5em 0;padding:.2em .5em}body:not(.skin-minerva) .mw-parser-output .hatnote-text{padding-left:.5em}body.skin-minerva .mw-parser-output .hatnote-icon{padding-right:8px}body.skin-minerva .mw-parser-output .hatnote-icon img{height:auto;width:16px}body.skin--responsive .mw-parser-output .hatnote a.new{color:#d73333}body.skin--responsive .mw-parser-output .hatnote a.new:visited{color:#a55858}</style> <div class="hatnote noprint nota-disambigua"> <div class="hatnote-content"><span class="noviewer hatnote-icon" typeof="mw:File"><span><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Nota_disambigua.svg/18px-Nota_disambigua.svg.png" decoding="async" width="18" height="18" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Nota_disambigua.svg/27px-Nota_disambigua.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Nota_disambigua.svg/36px-Nota_disambigua.svg.png 2x" data-file-width="200" data-file-height="200" /></span></span> <span class="hatnote-text"><a href="/wiki/Aiuto:Disambiguazione" title="Aiuto:Disambiguazione">Disambiguazione</a> – Se stai cercando altri significati, vedi <b><a href="/wiki/Lumen_(disambigua)" class="mw-disambig" title="Lumen (disambigua)">Lumen (disambigua)</a></b>.</span></div> </div> <p>Il <b>lumen</b> (simbolo: <b>lm</b>) è l'unità di misura del <a href="/wiki/Flusso_luminoso" title="Flusso luminoso">flusso luminoso</a>.<sup id="cite_ref-iupac_1-0" class="reference"><a href="#cite_note-iupac-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>In passato il lumen era un'unità di misura derivata, definita tramite la <a href="/wiki/Candela_(unit%C3%A0_di_misura)" title="Candela (unità di misura)">candela</a>, che è l'unità di <a href="/wiki/Intensit%C3%A0_luminosa" title="Intensità luminosa">intensità luminosa</a> ossia il flusso luminoso <i>visibile</i> emesso da una sorgente per unità di <a href="/wiki/Angolo_solido" title="Angolo solido">angolo solido</a> misurato in <a href="/wiki/Steradiante" title="Steradiante">steradianti</a>. La candela ha subìto diversi aggiornamenti della sua definizione passando da quella del 1967-1969 (emissione luminosa per unità di angolo solido in direzione perpendicolare a una superficie di area <sup>1</sup>/<sub>60</sub> di cm<small><sup>2</sup></small> di Platino alla temperatura di fusione) a quella più recente (emissione luminosa, in una determinata direzione, di una sorgente di radiazione monocromatica di frequenza 540×10<small><sup>12</sup></small> Hz con una intensità luminosa in questa direzione di <sup>1</sup>/<sub>683</sub> di Watt per steradiante). <br />Com'è noto dalla matematica la superficie di una sfera di raggio <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle r}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>r</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle r}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/0d1ecb613aa2984f0576f70f86650b7c2a132538" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.049ex; height:1.676ex;" alt="{\displaystyle r}"></span> è <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 4\pi r^{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>4</mn> <mi>π</mi> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 4\pi r^{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b81fcce302776a01dc66fc186a1ce0a616b4d772" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:4.597ex; height:2.676ex;" alt="{\displaystyle 4\pi r^{2}}"></span>, da cui l'angolo solido totale (in tutte le direzioni) nello spazio tridimensionale è <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 4\pi }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>4</mn> <mi>π</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 4\pi }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/057444bf35a0c22b19bcae1ef06e06ecdf8abe56" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:2.494ex; height:2.176ex;" alt="{\displaystyle 4\pi }"></span>. Pertanto una sorgente <a href="/wiki/Isotropia" title="Isotropia">isotropa</a> emetterà luce in maniera uniforme in tutte le direzioni ricoprendo un angolo solido di <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 4\pi }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>4</mn> <mi>π</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 4\pi }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/057444bf35a0c22b19bcae1ef06e06ecdf8abe56" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:2.494ex; height:2.176ex;" alt="{\displaystyle 4\pi }"></span> steradianti. Se la sua l'intensità luminosa è di 1 candela allora il suo flusso luminoso totale sarà <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 4\pi }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>4</mn> <mi>π</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 4\pi }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/057444bf35a0c22b19bcae1ef06e06ecdf8abe56" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:2.494ex; height:2.176ex;" alt="{\displaystyle 4\pi }"></span> lumen. </p><p>Nell'aggiornamento delle unità di misura e costanti fondamentali della fisica del <a href="/wiki/Sistema_internazionale_di_unit%C3%A0_di_misura" title="Sistema internazionale di unità di misura">Sistema Internazionale</a> (SI) pubblicato nel 2020<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> il <b>lumen</b> viene <b>definito</b> esattamente dalla relazione 683 lm = 1 W di potenza di radiazione luminosa monocromatica di frequenza di 540 × 10<small><sup>12</sup></small> Hz. La costante 683 rientra ora tra le sette costanti del SI. Quindi il lumen non viene più definito tramite l'unità di intensità luminosa <i>candela</i> (è stata abrogata la risoluzione del SI del 1979 che definiva la candela), ma è la candela che viene definita tramite il lumen. La frequenza di 540 × 10<small><sup>12</sup></small> Hz corrisponde a una lunghezza d'onda nel vuoto di 555,1712 nm, assai spesso arrotondata per brevità a 555 nm. </p><p>Il flusso luminoso <i>visibile</i>, misurato appunto in lumen, è pesato secondo la curva di sensibilità dell'occhio umano al variare delle lunghezze d'onda della radiazione luminosa ossia i diversi colori (vedere alla voce candela la sezione su <a href="/wiki/Candela_(unit%C3%A0_di_misura)#La_curva_di_sensibilità" title="Candela (unità di misura)">curva di sensibilità</a>). Questa curva è definita e adottata a livello internazionale<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> ed è rappresentata da una funzione <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V(\lambda )}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>V</mi> <mo stretchy="false">(</mo> <mi>λ</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V(\lambda )}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3b6def6cd8f362fe0e921a3ab1b1df61b838a5e1" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:4.952ex; height:2.843ex;" alt="{\displaystyle V(\lambda )}"></span> dove <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \lambda }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>λ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \lambda }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b43d0ea3c9c025af1be9128e62a18fa74bedda2a" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.355ex; height:2.176ex;" alt="{\displaystyle \lambda }"></span> è la lunghezza d'onda. Per convenzione il massimo di <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V(\lambda )}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>V</mi> <mo stretchy="false">(</mo> <mi>λ</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V(\lambda )}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3b6def6cd8f362fe0e921a3ab1b1df61b838a5e1" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:4.952ex; height:2.843ex;" alt="{\displaystyle V(\lambda )}"></span> è 1 per <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \lambda }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>λ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \lambda }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b43d0ea3c9c025af1be9128e62a18fa74bedda2a" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.355ex; height:2.176ex;" alt="{\displaystyle \lambda }"></span> = 555 nm, che è la lunghezza d'onda a cui l'occhio presenta la massima sensibilità e che è percepita come un colore verde. Per altre lunghezze d'onda <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V(\lambda )}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>V</mi> <mo stretchy="false">(</mo> <mi>λ</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V(\lambda )}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3b6def6cd8f362fe0e921a3ab1b1df61b838a5e1" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:4.952ex; height:2.843ex;" alt="{\displaystyle V(\lambda )}"></span> è minore di 1 e scende a valori molto bassi (inferiori a 0,005) per <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \lambda }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>λ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \lambda }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b43d0ea3c9c025af1be9128e62a18fa74bedda2a" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.355ex; height:2.176ex;" alt="{\displaystyle \lambda }"></span> < 420 nm e per <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \lambda }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>λ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \lambda }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b43d0ea3c9c025af1be9128e62a18fa74bedda2a" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.355ex; height:2.176ex;" alt="{\displaystyle \lambda }"></span> > 700 nm. La relazione tra flusso luminoso in lumen e potenza luminosa in Watt è espressa dalla relazione </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \phi _{v}=683\int _{0}^{\infty }\phi _{e}(\lambda )V(\lambda )\,d\lambda }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>ϕ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>v</mi> </mrow> </msub> <mo>=</mo> <mn>683</mn> <msubsup> <mo>∫</mo> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="normal">∞</mi> </mrow> </msubsup> <msub> <mi>ϕ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>e</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>λ</mi> <mo stretchy="false">)</mo> <mi>V</mi> <mo stretchy="false">(</mo> <mi>λ</mi> <mo stretchy="false">)</mo> <mspace width="thinmathspace" /> <mi>d</mi> <mi>λ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \phi _{v}=683\int _{0}^{\infty }\phi _{e}(\lambda )V(\lambda )\,d\lambda }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/82849858707a185dbca5aa0d7e74ec33d3984e48" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:27.573ex; height:5.843ex;" alt="{\displaystyle \phi _{v}=683\int _{0}^{\infty }\phi _{e}(\lambda )V(\lambda )\,d\lambda }"></span>   [in lumen]</dd></dl> <p>dove <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \phi _{e}(\lambda )}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>ϕ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>e</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>λ</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \phi _{e}(\lambda )}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/0de9f1aedeb2182063507db93b49d4e59cb3c3a9" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:5.548ex; height:2.843ex;" alt="{\displaystyle \phi _{e}(\lambda )}"></span> è la distribuzione spettrale in potenza della sorgente luminosa con potenza complessiva P </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle P=\int _{0}^{\infty }\phi _{e}(\lambda )\,d\lambda }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>P</mi> <mo>=</mo> <msubsup> <mo>∫</mo> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="normal">∞</mi> </mrow> </msubsup> <msub> <mi>ϕ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>e</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>λ</mi> <mo stretchy="false">)</mo> <mspace width="thinmathspace" /> <mi>d</mi> <mi>λ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle P=\int _{0}^{\infty }\phi _{e}(\lambda )\,d\lambda }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c2763a610cc089ba88e70044db57980d377c2ddb" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:18.077ex; height:5.843ex;" alt="{\displaystyle P=\int _{0}^{\infty }\phi _{e}(\lambda )\,d\lambda }"></span>   [in Watt]</dd></dl> <p>Per una sorgente monocromatica di lunghezza d'onda <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \lambda _{0}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>λ</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \lambda _{0}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/cfa5ad1eb6cdaf3d8dfd77991ee9ce7bdf169184" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.409ex; height:2.509ex;" alt="{\displaystyle \lambda _{0}}"></span> non v'è distribuzione spettrale, ossia <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \phi _{e}(\lambda )=P\ \delta (\lambda -\lambda _{0})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>ϕ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>e</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>λ</mi> <mo stretchy="false">)</mo> <mo>=</mo> <mi>P</mi> <mtext> </mtext> <mi>δ</mi> <mo stretchy="false">(</mo> <mi>λ</mi> <mo>−</mo> <msub> <mi>λ</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \phi _{e}(\lambda )=P\ \delta (\lambda -\lambda _{0})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/0243ba7885a195f1d6d2eb5702efbb0dd6ac7a14" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:20.436ex; height:2.843ex;" alt="{\displaystyle \phi _{e}(\lambda )=P\ \delta (\lambda -\lambda _{0})}"></span> (dove <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \delta }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>δ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \delta }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c5321cfa797202b3e1f8620663ff43c4660ea03a" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.049ex; height:2.343ex;" alt="{\displaystyle \delta }"></span> è la funzione <a href="/wiki/Delta_di_Dirac" title="Delta di Dirac">delta di Dirac</a>) e quindi <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \phi _{v}=683\ P\ V(\lambda _{0})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>ϕ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>v</mi> </mrow> </msub> <mo>=</mo> <mn>683</mn> <mtext> </mtext> <mi>P</mi> <mtext> </mtext> <mi>V</mi> <mo stretchy="false">(</mo> <msub> <mi>λ</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \phi _{v}=683\ P\ V(\lambda _{0})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/824ce5ad3aec0e81d77ae2eecb453a1113231088" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:17.914ex; height:2.843ex;" alt="{\displaystyle \phi _{v}=683\ P\ V(\lambda _{0})}"></span>. Pertanto per una sorgente di luce verde di lunghezza d'onda 555 nm e potenza 1 W si avrà che i due integrali valgono 1 e il flusso luminoso è 683 lumen. Per una distribuzione spettrale su una gamma di più lunghezze d'onda - e anche su una distribuzione continua su un intervallo di lunghezze d'onda - il primo integrale è sempre minore del secondo e quindi si avrà che il flusso luminoso è minore di 683 × P. Nel caso di luce percepita come bianca, la relazione tra flusso luminoso e potenza luminosa dipende sia dalla tonalità di bianco, esprimibile come temperatura equivalente di <a href="/wiki/Corpo_nero" title="Corpo nero">corpo nero</a>, che dalla sua <i>qualità</i>, quantificabile coll'<a href="/wiki/Indice_di_resa_cromatica" title="Indice di resa cromatica">indice di resa cromatica</a> (abbreviato con CRI da Color Rendering Index). Per sorgenti con tonalità tra 2700 e 4000 kelvin con CRI di 80 il flusso luminoso può raggiungere valori massimi di 403-427 lm/W, mentre con CRI di 90 non può oltrepassare i 387-406 lm/W<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup>. </p><p>Il lumen non è da confondere con la dicitura Ansi Lumen, che rappresenta il risultato della misurazione del flusso luminoso nelle condizioni standard suggerite dall’<a href="/wiki/American_National_Standards_Institute" title="American National Standards Institute">American National Standards Institute</a>.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Differenza_tra_lux_e_lumen">Differenza tra lux e lumen</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Lumen&veaction=edit&section=1" title="Modifica la sezione Differenza tra lux e lumen" class="mw-editsection-visualeditor"><span>modifica</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Lumen&action=edit&section=1" title="Edit section's source code: Differenza tra lux e lumen"><span>modifica wikitesto</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Il <b><a href="/wiki/Lux" title="Lux">lux</a></b> e il <b>lumen</b> sono due diverse misure del flusso luminoso, ma mentre il <b>lumen</b> è una misura della "quantità di luce" attraverso una sfera unitaria (incentrata sulla sorgente), il <b>lux</b> è una misura relativa all'area illuminata piana tangente la porzione sferica. 1 <b>lumen</b> su un'area di 1 m² corrisponde a 1 <b>lux</b>, mentre lo stesso <b>lumen</b> concentrato in 1 cm² corrisponde a 10 000 <b>lux</b>. </p><p>La differenza tra lux e lumen riguarda la misurazione di diverse caratteristiche della luce. Ecco una spiegazione dei due termini: </p><p>Lumen (lm): Il lumen è un'unità di misura per il flusso luminoso, ovvero la quantità totale di luce emessa da una sorgente luminosa in tutte le direzioni. Rappresenta la quantità totale di energia luminosa prodotta dalla sorgente, indipendentemente da dove questa energia viene indirizzata. In sostanza, il lumen misura la "potenza" della sorgente di luce. </p><p>Lux (lx): Il lux è un'unità di misura dell'illuminamento, ovvero la quantità di luce che cade su una superficie specifica. Rappresenta l'intensità della luce che raggiunge una superficie in relazione alla sua area. In altre parole, il lux misura la "quantità" di luce che arriva a una determinata area. </p><p>Quindi, per riassumere, il lumen misura la quantità totale di luce emessa da una sorgente, mentre il lux misura l'illuminamento, ovvero la quantità di luce che raggiunge una superficie specifica. È possibile avere una fonte luminosa con un alto flusso luminoso in lumen, ma se questa luce viene diffusa su un'ampia area, l'illuminamento in lux su quella superficie potrebbe essere basso. D'altra parte, una sorgente luminosa con un flusso luminoso più basso potrebbe fornire un illuminamento più elevato se concentrata su una superficie più piccola. </p><p><b>In sintesi, il lumen è una misura del flusso luminoso totale, mentre il lux è una misura dell'illuminamento su una superficie specifica.</b> </p><p>Infine il <b><a href="/wiki/Nit_(unit%C3%A0_di_misura)" title="Nit (unità di misura)">nit</a></b> è l'unità di misura della luminanza, grandezza fisica ottica non appartenente al Sistema Internazionale di unità di misura. </p> <div class="mw-heading mw-heading2"><h2 id="Note">Note</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Lumen&veaction=edit&section=2" title="Modifica la sezione Note" class="mw-editsection-visualeditor"><span>modifica</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Lumen&action=edit&section=2" title="Edit section's source code: Note"><span>modifica wikitesto</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-iupac-1"><a href="#cite_ref-iupac_1-0"><b>^</b></a> <span class="reference-text">(<span style="font-weight:bolder; font-size:80%"><abbr title="inglese">EN</abbr></span>) <a rel="nofollow" class="external text" href="http://goldbook.iupac.org/L03639.html">IUPAC Gold Book, "lumen"</a></span> </li> <li id="cite_note-2"><a href="#cite_ref-2"><b>^</b></a> <span class="reference-text"><cite class="citation pubblicazione" style="font-style:normal"> <a rel="nofollow" class="external text" href="https://www.bipm.org/documents/20126/41483022/SI-Brochure-9.pdf"><span style="font-style:italic;">Le Système international d'unités - The International System of Units</span></a> (<span style="font-weight: bolder; font-size:80%"><abbr title="documento in formato PDF">PDF</abbr></span>), 9ª edizione, Bureau international des poids et mesures, 2020.</cite></span> </li> <li id="cite_note-3"><a href="#cite_ref-3"><b>^</b></a> <span class="reference-text"><cite class="citation web" style="font-style:normal">(<span style="font-weight:bolder; font-size:80%"><abbr title="inglese">EN</abbr></span>) <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190501164428/http://www.kayelaby.npl.co.uk/general_physics/2_5/2_5_3.html"><span style="font-style:italic;">2.5.3 Photometry - Photopic spectral luminous efficiency function V(λ)</span></a>, su <span style="font-style:italic;">kayelaby.npl.co.uk</span>, Kaye&Laby - National Physical Laboratory <small>(archiviato dall'<abbr title="http://www.kayelaby.npl.co.uk/general_physics/2_5/2_5_3.html">url originale</abbr> il 1º maggio 2019)</small>.</cite></span> </li> <li id="cite_note-4"><a href="#cite_ref-4"><b>^</b></a> <span class="reference-text"><cite class="citation pubblicazione" style="font-style:normal">(<span style="font-weight:bolder; font-size:80%"><abbr title="inglese">EN</abbr></span>) Geoges Zissis, Paolo Bertoldi e T. Serrenho, <a rel="nofollow" class="external text" href="https://publications.jrc.ec.europa.eu/repository/bitstream/JRC122760/status_of_led_lighting_world_market_2020_final_rev_2.pdf"><span style="font-style:italic;">Update on the Status of LED-Lighting world market since 2018</span></a> (<span style="font-weight: bolder; font-size:80%"><abbr title="documento in formato PDF">PDF</abbr></span>), Joint Research Centre - European Commission, 12 gennaio 2021.</cite> Vedi fig. 7 (a) a pag. 10.</span> </li> <li id="cite_note-5"><a href="#cite_ref-5"><b>^</b></a> <span class="reference-text"><cite class="citation web" style="font-style:normal"> <a rel="nofollow" class="external text" href="https://meeting-hub.net/blog/cosa-sono-gli-ansi-lumen/"><span style="font-style:italic;">Videoproiettore: cosa sono gli ansi lumen?</span></a>, su <span style="font-style:italic;">meeting-hub.net</span>.</cite></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="Voci_correlate">Voci correlate</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Lumen&veaction=edit&section=3" title="Modifica la sezione Voci correlate" class="mw-editsection-visualeditor"><span>modifica</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Lumen&action=edit&section=3" title="Edit section's source code: Voci correlate"><span>modifica wikitesto</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Lux" title="Lux">Lux</a></li> <li><a href="/wiki/Nit_(unit%C3%A0_di_misura)" title="Nit (unità di misura)">Nit (unità di misura)</a></li> <li><a href="/wiki/Candela_(unit%C3%A0_di_misura)" title="Candela (unità di misura)">Candela (unità di misura)</a></li> <li><a href="/wiki/Efficienza_luminosa" title="Efficienza luminosa">Efficienza luminosa</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Altri_progetti">Altri progetti</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Lumen&veaction=edit&section=4" title="Modifica la sezione Altri progetti" class="mw-editsection-visualeditor"><span>modifica</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Lumen&action=edit&section=4" title="Edit section's source code: Altri progetti"><span>modifica wikitesto</span></a><span class="mw-editsection-bracket">]</span></span></div> <div id="interProject" class="toccolours" style="display: none; clear: both; margin-top: 2em"><p id="sisterProjects" style="background-color: #efefef; color: black; font-weight: bold; margin: 0"><span>Altri progetti</span></p><ul title="Collegamenti verso gli altri progetti Wikimedia"> <li class="" title=""><a href="https://it.wiktionary.org/wiki/lumen" class="extiw" title="wikt:lumen">Wikizionario</a></li></ul></div> <ul><li><span typeof="mw:File"><a href="https://it.wiktionary.org/wiki/" title="Collabora a Wikizionario"><img alt="Collabora a Wikizionario" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Wiktionary_small.svg/18px-Wiktionary_small.svg.png" decoding="async" width="18" height="18" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Wiktionary_small.svg/27px-Wiktionary_small.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Wiktionary_small.svg/36px-Wiktionary_small.svg.png 2x" data-file-width="350" data-file-height="350" /></a></span> <a href="https://it.wiktionary.org/wiki/" class="extiw" title="wikt:">Wikizionario</a> contiene il lemma di dizionario «<b><a href="https://it.wiktionary.org/wiki/lumen" class="extiw" title="wikt:lumen">lumen</a></b>»</li></ul> <div class="mw-heading mw-heading2"><h2 id="Collegamenti_esterni">Collegamenti esterni</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Lumen&veaction=edit&section=5" title="Modifica la sezione Collegamenti esterni" class="mw-editsection-visualeditor"><span>modifica</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Lumen&action=edit&section=5" title="Edit section's source code: Collegamenti esterni"><span>modifica wikitesto</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.energysavinglamps.info/photometry_applet.html">Calcolo e visualizzazione di grandezze fotometriche</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20080611060104/http://www.energysavinglamps.info/photometry_applet.html">Archiviato</a> l'11 giugno 2008 in <a href="/wiki/Internet_Archive" title="Internet Archive">Internet Archive</a>. — Java applet grafico per lux/lumen/candela</li> <li><a rel="nofollow" class="external text" href="http://www.electroyou.it/vis_resource.php?section=Lezio&id=177">lumen e candele - ElectroYou</a> - Articolo sulle due più importanti grandezze fotometriche.</li></ul> <style data-mw-deduplicate="TemplateStyles:r141815314">.mw-parser-output .navbox{border:1px solid #aaa;clear:both;margin:auto;padding:2px;width:100%}.mw-parser-output .navbox th{padding-left:1em;padding-right:1em;text-align:center}.mw-parser-output .navbox>tbody>tr:first-child>th{background:#ccf;font-size:90%;width:100%;color:var(--color-base,black)}.mw-parser-output .navbox_navbar{float:left;margin:0;padding:0 10px 0 0;text-align:left;width:6em}.mw-parser-output .navbox_title{font-size:110%}.mw-parser-output .navbox_abovebelow{background:#ddf;font-size:90%;font-weight:normal}.mw-parser-output .navbox_group{background:#ddf;font-size:90%;padding:0 10px;white-space:nowrap}.mw-parser-output .navbox_list{font-size:90%;width:100%}.mw-parser-output .navbox_list a{white-space:nowrap}html:not(.vector-feature-night-mode-enabled) .mw-parser-output .navbox_odd{background:#fdfdfd;color:var(--color-base,black)}html:not(.vector-feature-night-mode-enabled) .mw-parser-output .navbox_even{background:#f7f7f7;color:var(--color-base,black)}.mw-parser-output .navbox a.mw-selflink{color:var(--color-base,black)}.mw-parser-output .navbox_center{text-align:center}.mw-parser-output .navbox .navbox_image{padding-left:7px;vertical-align:middle;width:0}.mw-parser-output .navbox+.navbox{margin-top:-1px}.mw-parser-output .navbox .mw-collapsible-toggle{font-weight:normal;text-align:right;width:7em}body.skin--responsive .mw-parser-output .navbox_image img{max-width:none!important}.mw-parser-output .subnavbox{margin:-3px;width:100%}.mw-parser-output .subnavbox_group{background:#e6e6ff;padding:0 10px}@media screen{html.skin-theme-clientpref-night .mw-parser-output .navbox>tbody>tr:first-child>th{background:var(--background-color-interactive)!important}html.skin-theme-clientpref-night .mw-parser-output .navbox th{color:var(--color-base)!important}html.skin-theme-clientpref-night .mw-parser-output .navbox_abovebelow,html.skin-theme-clientpref-night .mw-parser-output .navbox_group{background:var(--background-color-interactive-subtle)!important}html.skin-theme-clientpref-night .mw-parser-output .subnavbox_group{background:var(--background-color-neutral-subtle)!important}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbox>tbody>tr:first-child>th{background:var(--background-color-interactive)!important}html.skin-theme-clientpref-os .mw-parser-output .navbox th{color:var(--color-base)!important}html.skin-theme-clientpref-os .mw-parser-output .navbox_abovebelow,html.skin-theme-clientpref-os .mw-parser-output .navbox_group{background:var(--background-color-interactive-subtle)!important}html.skin-theme-clientpref-os .mw-parser-output .subnavbox_group{background:var(--background-color-neutral-subtle)!important}}</style><table class="navbox mw-collapsible mw-collapsed noprint metadata" id="navbox-Unità_di_misura"><tbody><tr><th colspan="2"><div class="navbox_navbar"><div class="noprint plainlinks" style="background-color:transparent; padding:0; font-size:xx-small; color:var(--color-base, #000000); white-space:nowrap;"><a href="/wiki/Template:Unit%C3%A0_di_misura" title="Template:Unità di misura"><span title="Vai alla pagina del template">V</span></a> · <a href="/wiki/Discussioni_template:Unit%C3%A0_di_misura" title="Discussioni template:Unità di misura"><span title="Discuti del template">D</span></a> · <a class="external text" href="https://it.wikipedia.org/w/index.php?title=Template:Unit%C3%A0_di_misura&action=edit"><span title="Modifica il template. Usa l'anteprima prima di salvare">M</span></a></div></div><span class="navbox_title"><a href="/wiki/Unit%C3%A0_di_misura" title="Unità di misura">Unità di misura</a></span></th></tr><tr><th colspan="2" class="navbox_abovebelow"><a href="/wiki/Sistemi_di_misurazione" title="Sistemi di misurazione">Sistemi di misurazione</a><b> ·</b> <a href="/wiki/Conversione_delle_unit%C3%A0_di_misura" title="Conversione delle unità di misura">Conversione delle unità di misura</a><b> ·</b> <a href="/wiki/Sistema_consuetudinario_statunitense" title="Sistema consuetudinario statunitense">Sistema consuetudinario statunitense</a><b> ·</b> <a href="/wiki/Sistema_imperiale_britannico" title="Sistema imperiale britannico">Sistema imperiale britannico</a><b> ·</b> <a href="/wiki/Antiche_unit%C3%A0_di_misura_italiane" title="Antiche unità di misura italiane">Antiche unità di misura italiane</a><b> ·</b> <a href="/wiki/Unit%C3%A0_di_misura_giapponesi" title="Unità di misura giapponesi">Unità di misura giapponesi</a></th></tr><tr><th colspan="1" class="navbox_group" style="text-align:center; width:22%;"><a href="/wiki/Sistema_internazionale_di_unit%C3%A0_di_misura" title="Sistema internazionale di unità di misura">Sistema internazionale</a></th><td colspan="1" class="navbox_list navbox_odd"><table class="subnavbox"><tbody><tr><th class="subnavbox_group" style="text-align:center; width:22%;"><a href="/wiki/Unit%C3%A0_fondamentali_del_sistema_internazionale" title="Unità fondamentali del sistema internazionale">Unità di base</a></th><td colspan="1"><a href="/wiki/Secondo" title="Secondo">secondo</a><b> ·</b> <a href="/wiki/Metro" title="Metro">metro</a><b> ·</b> <a href="/wiki/Chilogrammo" title="Chilogrammo">chilogrammo</a><b> ·</b> <a href="/wiki/Ampere" title="Ampere">ampere</a><b> ·</b> <a href="/wiki/Kelvin" title="Kelvin">kelvin</a><b> ·</b> <a href="/wiki/Mole" title="Mole">mole</a><b> ·</b> <a href="/wiki/Candela_(unit%C3%A0_di_misura)" title="Candela (unità di misura)">candela</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità derivate</th><td colspan="1"><a href="/wiki/Hertz" title="Hertz">hertz</a><b> ·</b> <a href="/wiki/Newton_(unit%C3%A0_di_misura)" title="Newton (unità di misura)">newton</a><b> ·</b> <a href="/wiki/Pascal_(unit%C3%A0_di_misura)" title="Pascal (unità di misura)">pascal</a><b> ·</b> <a href="/wiki/Joule" title="Joule">joule</a><b> ·</b> <a href="/wiki/Watt" title="Watt">watt</a><b> ·</b> <a href="/wiki/Coulomb" title="Coulomb">coulomb</a><b> ·</b> <a href="/wiki/Volt" title="Volt">volt</a><b> ·</b> <a href="/wiki/Ohm" title="Ohm">ohm</a><b> ·</b> <a href="/wiki/Siemens_(unit%C3%A0_di_misura)" title="Siemens (unità di misura)">siemens</a><b> ·</b> <a href="/wiki/Farad" title="Farad">farad</a><b> ·</b> <a href="/wiki/Tesla_(unit%C3%A0_di_misura)" title="Tesla (unità di misura)">tesla</a><b> ·</b> <a href="/wiki/Weber_(unit%C3%A0_di_misura)" title="Weber (unità di misura)">weber</a><b> ·</b> <a href="/wiki/Henry_(unit%C3%A0_di_misura)" title="Henry (unità di misura)">henry</a><b> ·</b> <a href="/wiki/Grado_Celsius" title="Grado Celsius">grado Celsius</a><b> ·</b> <a href="/wiki/Radiante" title="Radiante">radiante</a><b> ·</b> <a href="/wiki/Steradiante" title="Steradiante">steradiante</a><b> ·</b> <a class="mw-selflink selflink">lumen</a><b> ·</b> <a href="/wiki/Lux" title="Lux">lux</a><b> ·</b> <a href="/wiki/Becquerel" title="Becquerel">becquerel</a><b> ·</b> <a href="/wiki/Gray_(unit%C3%A0_di_misura)" title="Gray (unità di misura)">gray</a><b> ·</b> <a href="/wiki/Sievert" title="Sievert">sievert</a><b> ·</b> <a href="/wiki/Katal" title="Katal">katal</a></td></tr></tbody></table></td></tr><tr><th colspan="1" class="navbox_group" style="text-align:center; width:22%;"><a href="/wiki/Sistema_CGS" title="Sistema CGS">Sistema CGS</a></th><td colspan="1" class="navbox_list navbox_even"><table class="subnavbox"><tbody><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità di base</th><td colspan="1"><a href="/wiki/Metro" title="Metro">centimetro</a><b> ·</b> <a href="/wiki/Grammo" title="Grammo">grammo</a><b> ·</b> <a href="/wiki/Secondo" title="Secondo">secondo</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità derivate</th><td colspan="1"><a href="/wiki/Dyne" title="Dyne">dyne</a><b> ·</b> <a href="/wiki/Erg" title="Erg">erg</a><b> ·</b> <a href="/wiki/Baria" title="Baria">baria</a><b> ·</b> <a href="/wiki/Poise" title="Poise">poise</a><b> ·</b> <a href="/wiki/Statcoulomb" title="Statcoulomb">statcoulomb</a><b> ·</b> <a href="/wiki/Statvolt" title="Statvolt">statvolt</a><b> ·</b> <a href="/wiki/Oersted_(unit%C3%A0_di_misura)" title="Oersted (unità di misura)">oersted</a><b> ·</b> <a href="/wiki/Gauss_(unit%C3%A0_di_misura)" title="Gauss (unità di misura)">gauss</a><b> ·</b> <a href="/wiki/Maxwell_(unit%C3%A0_di_misura)" title="Maxwell (unità di misura)">maxwell</a><b> ·</b> <a href="/wiki/Rayl" title="Rayl">rayl</a><b> ·</b> <a href="/wiki/Gal" title="Gal">gal</a></td></tr></tbody></table></td></tr><tr><th colspan="1" class="navbox_group" style="text-align:center; width:22%;"><a href="/wiki/Sistema_pratico_degli_ingegneri" title="Sistema pratico degli ingegneri">Sistema Tecnico - MFS</a></th><td colspan="1" class="navbox_list navbox_odd"><table class="subnavbox"><tbody><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità di base</th><td colspan="1"><a href="/wiki/Metro" title="Metro">metro</a><b> ·</b> <a href="/wiki/Chilogrammo_forza" title="Chilogrammo forza">chilogrammo forza</a><b> ·</b> <a href="/wiki/Secondo" title="Secondo">secondo</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità derivate</th><td colspan="1"><a href="/wiki/Unit%C3%A0_tecnica_di_massa" title="Unità tecnica di massa">unità tecnica di massa</a></td></tr></tbody></table></td></tr><tr><th colspan="1" class="navbox_group" style="text-align:center; width:22%;"><a href="/wiki/Sistema_MTS" title="Sistema MTS">Sistema MTS</a></th><td colspan="1" class="navbox_list navbox_even"><table class="subnavbox"><tbody><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità di base</th><td colspan="1"><a href="/wiki/Metro" title="Metro">metro</a><b> ·</b> <a href="/wiki/Tonnellata" title="Tonnellata">tonnellata</a><b> ·</b> <a href="/wiki/Secondo" title="Secondo">secondo</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità derivate</th><td colspan="1"><a href="/wiki/Sth%C3%A8ne" title="Sthène">sthène</a><b> ·</b> <a href="/wiki/Joule" title="Joule">chilojoule</a><b> ·</b> <a href="/wiki/Watt" title="Watt">chilowatt</a><b> ·</b> <a href="/wiki/Pi%C3%A8ze" title="Pièze">pièze</a></td></tr></tbody></table></td></tr><tr><th colspan="1" class="navbox_group" style="text-align:center; width:22%;"><a href="/wiki/Unit%C3%A0_atomiche" title="Unità atomiche">Unità atomiche</a></th><td colspan="1" class="navbox_list navbox_odd"><table class="subnavbox"><tbody><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità di base</th><td colspan="1"><a href="/wiki/Raggio_di_Bohr" title="Raggio di Bohr">raggio di Bohr</a><b> ·</b> <a href="/wiki/Massa_a_riposo_dell%27elettrone" title="Massa a riposo dell'elettrone">massa a riposo dell'elettrone</a><b> ·</b> <a href="/wiki/Carica_elementare" title="Carica elementare">carica elementare</a><b> ·</b> <a href="/wiki/Costante_di_Planck#Valore" title="Costante di Planck">costante di Dirac</a><b> ·</b> <a href="/wiki/Energia_di_Hartree" title="Energia di Hartree">energia di Hartree</a></td></tr></tbody></table></td></tr><tr><th colspan="1" class="navbox_group" style="text-align:center; width:22%;"><a href="/wiki/Unit%C3%A0_di_misura_di_Planck" title="Unità di misura di Planck">Unità di misura di Planck</a></th><td colspan="1" class="navbox_list navbox_even"><table class="subnavbox"><tbody><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità di base</th><td colspan="1"><a href="/wiki/Tempo_di_Planck" title="Tempo di Planck">tempo di Planck</a><b> ·</b> <a href="/wiki/Lunghezza_di_Planck" title="Lunghezza di Planck">lunghezza di Planck</a><b> ·</b> <a href="/wiki/Massa_di_Planck" title="Massa di Planck">massa di Planck</a><b> ·</b> <a href="/wiki/Carica_di_Planck" title="Carica di Planck">carica di Planck</a><b> ·</b> <a href="/wiki/Temperatura_di_Planck" title="Temperatura di Planck">temperatura di Planck</a><b> ·</b> <a href="/wiki/Costante_di_Planck" title="Costante di Planck">quanto del momento angolare</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;">Unità derivate</th><td colspan="1"><a href="/wiki/Energia_di_Planck" title="Energia di Planck">energia di Planck</a><b> ·</b> <a href="/wiki/Forza_di_Planck" class="mw-redirect" title="Forza di Planck">forza di Planck</a><b> ·</b> <a href="/wiki/Potenza_di_Planck" class="mw-redirect" title="Potenza di Planck">potenza di Planck</a><b> ·</b> <a href="/wiki/Densit%C3%A0_di_Planck" class="mw-redirect" title="Densità di Planck">densità di Planck</a><b> ·</b> <a href="/wiki/Frequenza_angolare_di_Planck" class="mw-redirect" title="Frequenza angolare di Planck">frequenza angolare di Planck</a><b> ·</b> <a href="/wiki/Pressione_di_Planck" class="mw-redirect" title="Pressione di Planck">pressione di Planck</a><b> ·</b> <a href="/wiki/Corrente_di_Planck" class="mw-redirect" title="Corrente di Planck">corrente di Planck</a><b> ·</b> <a href="/wiki/Tensione_di_Planck" class="mw-redirect" title="Tensione di Planck">tensione di Planck</a><b> ·</b> <a href="/wiki/Resistenza_di_Planck" class="mw-redirect" title="Resistenza di Planck">resistenza di Planck</a></td></tr></tbody></table></td></tr><tr><th colspan="1" class="navbox_group" style="text-align:center; width:22%;">Altre unità di misura</th><td colspan="1" class="navbox_list navbox_odd"><table class="subnavbox"><tbody><tr><th class="subnavbox_group" style="text-align:center; width:22%;"><a href="/wiki/Area" title="Area">Area</a></th><td colspan="1"><a href="/wiki/Ettaro" title="Ettaro">ettaro</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;"><a href="/wiki/Densit%C3%A0_lineare" title="Densità lineare">Densità lineare</a></th><td colspan="1"><a href="/wiki/Denaro_(unit%C3%A0_di_misura)" title="Denaro (unità di misura)">denaro</a><b> ·</b> <a href="/wiki/Tex_(unit%C3%A0_di_misura)" title="Tex (unità di misura)">tex</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;"><a href="/wiki/Entropia" title="Entropia">Entropia</a></th><td colspan="1"><a href="/wiki/Clausius_(unit%C3%A0_di_misura)" title="Clausius (unità di misura)">clausius</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;"><a href="/wiki/Massa_(fisica)" title="Massa (fisica)">Massa</a></th><td colspan="1"><a href="/wiki/Grano_(unit%C3%A0_di_misura)" title="Grano (unità di misura)">grano</a><b> ·</b> <a href="/wiki/Scruple" title="Scruple">scruple</a><b> ·</b> <a href="/wiki/Dramma_(unit%C3%A0_di_misura)" title="Dramma (unità di misura)">dramma</a><b> ·</b> <a href="/wiki/Oncia_(unit%C3%A0_di_misura)" title="Oncia (unità di misura)">oncia</a><b> ·</b> <a href="/wiki/Libbra" title="Libbra">libbra</a><b> ·</b> <a href="/wiki/Pietra_(unit%C3%A0_di_misura)" class="mw-redirect" title="Pietra (unità di misura)">pietra</a><b> ·</b> <a href="/wiki/Quarto_(unit%C3%A0_di_misura)" title="Quarto (unità di misura)">quarto</a><b> ·</b> <a href="/wiki/Slug_(unit%C3%A0_di_misura)" title="Slug (unità di misura)">slug</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;"><a href="/wiki/Temperatura" title="Temperatura">Temperatura</a></th><td colspan="1"><a href="/wiki/Grado_R%C3%B8mer" title="Grado Rømer">grado Rømer</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;"><a href="/wiki/Energia" title="Energia">Energia</a></th><td colspan="1"><a href="/wiki/Caloria" title="Caloria">caloria</a><b> ·</b> <a href="/wiki/Frigoria" title="Frigoria">frigoria</a></td></tr><tr><th class="subnavbox_group" style="text-align:center; width:22%;"><a href="/wiki/Lunghezza" title="Lunghezza">lunghezza</a> in astronomia</th><td colspan="1"><a href="/wiki/Unit%C3%A0_astronomica" title="Unità astronomica">unità astronomica</a><b> ·</b> <a href="/wiki/Anno_luce" title="Anno luce">anno luce</a><b> ·</b> <a href="/wiki/Parsec" title="Parsec">parsec</a></td></tr></tbody></table></td></tr></tbody></table> <div class="noprint" style="width:100%; padding: 3px 0; display: flex; flex-wrap: wrap; row-gap: 4px; column-gap: 8px; box-sizing: border-box;"><div style="flex-basis: calc( 100% / 3 - 8px * 2/3 );"><style data-mw-deduplicate="TemplateStyles:r140555418">.mw-parser-output .itwiki-template-occhiello{width:100%;line-height:25px;border:1px solid #CCF;background-color:#F0EEFF;box-sizing:border-box}.mw-parser-output .itwiki-template-occhiello-progetto{background-color:#FAFAFA}@media screen{html.skin-theme-clientpref-night .mw-parser-output .itwiki-template-occhiello{background-color:#202122;border-color:#54595D}html.skin-theme-clientpref-night .mw-parser-output .itwiki-template-occhiello-progetto{background-color:#282929}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .itwiki-template-occhiello{background-color:#202122;border-color:#54595D}html.skin-theme-clientpref-os .mw-parser-output .itwiki-template-occhiello-progetto{background-color:#282929}}</style><div class="itwiki-template-occhiello"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Nuvola_apps_katomic.svg" class="mw-file-description" title="Fisica"><img alt=" " src="//upload.wikimedia.org/wikipedia/commons/thumb/5/55/Nuvola_apps_katomic.svg/25px-Nuvola_apps_katomic.svg.png" decoding="async" width="25" height="25" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/55/Nuvola_apps_katomic.svg/38px-Nuvola_apps_katomic.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/55/Nuvola_apps_katomic.svg/50px-Nuvola_apps_katomic.svg.png 2x" data-file-width="128" data-file-height="128" /></a></span> <b><a href="/wiki/Portale:Fisica" title="Portale:Fisica">Portale Fisica</a></b></div></div><div style="flex-basis: calc( 100% / 3 - 8px * 2/3 );"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r140555418"><div class="itwiki-template-occhiello"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Crystal_kcontrol_2.svg" class="mw-file-description" title="Ingegneria"><img alt=" " src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Crystal_kcontrol_2.svg/23px-Crystal_kcontrol_2.svg.png" decoding="async" width="23" height="25" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Crystal_kcontrol_2.svg/36px-Crystal_kcontrol_2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Crystal_kcontrol_2.svg/47px-Crystal_kcontrol_2.svg.png 2x" data-file-width="93" data-file-height="99" /></a></span> <b><a href="/wiki/Portale:Ingegneria" title="Portale:Ingegneria">Portale Ingegneria</a></b></div></div><div style="flex-basis: calc( 100% / 3 - 8px * 2/3 );"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r140555418"><div class="itwiki-template-occhiello"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Unbalanced_scales_simpler.svg" class="mw-file-description" title="Metrologia"><img alt=" " src="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/Unbalanced_scales_simpler.svg/25px-Unbalanced_scales_simpler.svg.png" decoding="async" width="25" height="22" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/17/Unbalanced_scales_simpler.svg/38px-Unbalanced_scales_simpler.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/17/Unbalanced_scales_simpler.svg/50px-Unbalanced_scales_simpler.svg.png 2x" data-file-width="400" data-file-height="354" /></a></span> <b><a href="/wiki/Portale:Metrologia" title="Portale:Metrologia">Portale Metrologia</a></b></div></div></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1&useformat=desktop" alt="" width="1" height="1" style="border: none; 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