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class="vector-toc-link" href="#Black_light"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.3</span> <span>Black light</span> </div> </a> <ul id="toc-Black_light-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Seeing_in_the_dark" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Seeing_in_the_dark"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Seeing in the dark</span> </div> </a> <ul id="toc-Seeing_in_the_dark-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Human_dog_horse" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Human_dog_horse"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Human dog horse</span> </div> </a> <ul id="toc-Human_dog_horse-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item 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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">From Wikiversity</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="en" dir="ltr"><p><b>Night vision</b> is the ability to see in (relative) darkness. All natural vision involves reception of some light by the eye. This is true even in the dark; vision is possible only when light is present. Often, what appears to be total darkness is not the absence of light but rather the poor reception of available light. To see well in the dark, humans either enhance reception of limited available light, or provide more light. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Light_in_the_dark">Light in the dark</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Night_vision&veaction=edit&section=1" title="Edit section: Light in the dark" class="mw-editsection-visualeditor"><span>edit</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Night_vision&action=edit&section=1" title="Edit section's source code: Light in the dark"><span>edit source</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Many techniques and technologies for improving night vision involve reception of certain frequency bands (colors) of light. These frequency bands include: </p> <ul><li>infrared light (heat)</li> <li>red light</li> <li>soft ultraviolet (UV) light (also known as <a href="https://en.wikipedia.org/wiki/Blacklight" class="extiw" title="w:Blacklight">blacklight</a>)</li></ul> <div class="mw-heading mw-heading3"><h3 id="Infrared_light">Infrared light</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Night_vision&veaction=edit&section=2" title="Edit section: Infrared light" class="mw-editsection-visualeditor"><span>edit</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Night_vision&action=edit&section=2" title="Edit section's source code: Infrared light"><span>edit source</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Wiki_deer.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f1/Wiki_deer.jpg/220px-Wiki_deer.jpg" decoding="async" width="220" height="131" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f1/Wiki_deer.jpg/330px-Wiki_deer.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/f/f1/Wiki_deer.jpg 2x" data-file-width="404" data-file-height="240" /></a><figcaption>A deer's pelt is insulating, keeping the animal warm and limiting the amount of IR light emitted; the eyes and mouth, uninsulated, glow with IR light</figcaption></figure> <p>Because the human eye does not detect IR light, our visual detection of this light requires some kind of electronic imaging device. Many military and civilian SAR helicopters are equipped with forward looking infra red (FLIR)<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> devices. </p><p>Infrared (IR) imaging is used to search for clues that are expected to have a temperature far above ambient. Thus IR imaging is used most often at night (when ambient temperatures are lower) but also may be used in daylight, especially in cold weather. IR-detectable clues include hot engines, campfires, and live subjects. IR imaging cannot detect a clue that is not above ambient temperature, due to lack of contrast between clue and background. Thus, IR imaging may be ineffective during early night in hot deserts, and when the subject is under cover, dressed in heavy winter clothes, or deceased. </p><p><br /> </p> <div class="mw-heading mw-heading3"><h3 id="Red_light">Red light</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Night_vision&veaction=edit&section=3" title="Edit section: Red light" class="mw-editsection-visualeditor"><span>edit</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Night_vision&action=edit&section=3" title="Edit section's source code: Red light"><span>edit source</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Cone-absorbance-en.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/9c/Cone-absorbance-en.svg/220px-Cone-absorbance-en.svg.png" decoding="async" width="220" height="138" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/9c/Cone-absorbance-en.svg/330px-Cone-absorbance-en.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/9c/Cone-absorbance-en.svg/440px-Cone-absorbance-en.svg.png 2x" data-file-width="550" data-file-height="346" /></a><figcaption>Spectra of the three human photopsins (red, green, and blue) and of human rhodopsin (dashed)</figcaption></figure> <p>In humans, the rod cells that provide normal night vision are not sensitive to red light. Thus, a source of red light (such as a flashlight with a red filter) can be used to provide sufficient light for the cone cells without "blinding" the rod cells. </p> <div class="mw-heading mw-heading3"><h3 id="Black_light">Black light</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Night_vision&veaction=edit&section=4" title="Edit section: Black light" class="mw-editsection-visualeditor"><span>edit</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Night_vision&action=edit&section=4" title="Edit section's source code: Black light"><span>edit source</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Sorpion_Under_Blacklight.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/86/Sorpion_Under_Blacklight.jpg/220px-Sorpion_Under_Blacklight.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/86/Sorpion_Under_Blacklight.jpg/330px-Sorpion_Under_Blacklight.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/86/Sorpion_Under_Blacklight.jpg/440px-Sorpion_Under_Blacklight.jpg 2x" data-file-width="1024" data-file-height="768" /></a><figcaption>Scorpion under black light</figcaption></figure> <p>Scorpions appear black in daylight but under black light they glow blue. Black light flashlights are used to find scorpions in the wild. </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Airman_Battle_Uniform_washing_effects.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Airman_Battle_Uniform_washing_effects.jpg/220px-Airman_Battle_Uniform_washing_effects.jpg" decoding="async" width="220" height="347" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Airman_Battle_Uniform_washing_effects.jpg/330px-Airman_Battle_Uniform_washing_effects.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Airman_Battle_Uniform_washing_effects.jpg/440px-Airman_Battle_Uniform_washing_effects.jpg 2x" data-file-width="1083" data-file-height="1710" /></a><figcaption>Airman Battle Uniform</figcaption></figure> <p>Humans normally do not glow under black light, but often our clothing does. Most laundry detergents contain optical brighteners<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>, fluorescent dyes that absorb black light and emit blue light. These dyes make clothing appear brighter under daylight; under black light, they glow (fluoresce<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>) blue. Black light may be used at night to search for a subject's clothing. Because these dyes are in most laundry detergents, even in those labeled "no dyes", it may be not helpful to ask the subject's household members what brand of laundry detergent they use. Shining a black light on a sample of the subject's clothing may be helpful. </p><p>In 2007, the United States Air Force distributed laundry instructions for camouflage uniforms that included the instruction to use no detergents containing these dyes.<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> The Air Force later rescinded this instruction on the ground that research by the US Army found the effect was not important in the context of military combat.<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><p>Because horses' eyes are highly receptive for blue light, the combination of black light flashlights and mounted SAR field teams may be particularly effective. </p> <div class="mw-heading mw-heading2"><h2 id="Seeing_in_the_dark">Seeing in the dark</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Night_vision&veaction=edit&section=5" title="Edit section: Seeing in the dark" class="mw-editsection-visualeditor"><span>edit</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Night_vision&action=edit&section=5" title="Edit section's source code: Seeing in the dark"><span>edit source</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Reception of limited available light can be enhanced by using advanced technology and/or ancient behaviors most widely used by trackers and hunters. </p> <ul><li>electronics</li></ul> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Nightvision.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/52/Nightvision.jpg/220px-Nightvision.jpg" decoding="async" width="220" height="144" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/52/Nightvision.jpg/330px-Nightvision.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/52/Nightvision.jpg/440px-Nightvision.jpg 2x" data-file-width="512" data-file-height="335" /></a><figcaption>Scene viewed through an image intensifier</figcaption></figure> <ul><li>larger lenses: animals with very large eyes (eyeballs) tend to have very large lenses. Thus, horses have far better night vision than humans do. Humans can enhance their own night vision by using binoculars or scopes with lenses of very large diameter. All else being equal, due to the high cost of manufacturing large high quality lenses, these devices are far more expensive than others.</li></ul> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Night_Scope_on_M249.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Night_Scope_on_M249.jpg/220px-Night_Scope_on_M249.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Night_Scope_on_M249.jpg/330px-Night_Scope_on_M249.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Night_Scope_on_M249.jpg/440px-Night_Scope_on_M249.jpg 2x" data-file-width="3072" data-file-height="2304" /></a><figcaption>A night scope mounted on a military weapon</figcaption></figure> <ul><li>rods instead of cones</li></ul> <ul><li>peripheral instead of central vision</li></ul> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Netzhautlk-augekorp.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Netzhautlk-augekorp.jpg/220px-Netzhautlk-augekorp.jpg" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Netzhautlk-augekorp.jpg/330px-Netzhautlk-augekorp.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Netzhautlk-augekorp.jpg/440px-Netzhautlk-augekorp.jpg 2x" data-file-width="730" data-file-height="730" /></a><figcaption>Left eye scene on retina (simulation)</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Auge_Hund_Diagramm_engl.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/73/Auge_Hund_Diagramm_engl.jpg/220px-Auge_Hund_Diagramm_engl.jpg" decoding="async" width="220" height="101" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/73/Auge_Hund_Diagramm_engl.jpg/330px-Auge_Hund_Diagramm_engl.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/73/Auge_Hund_Diagramm_engl.jpg/440px-Auge_Hund_Diagramm_engl.jpg 2x" data-file-width="1347" data-file-height="616" /></a><figcaption>Human vs dog</figcaption></figure> <div class="mw-heading mw-heading2"><h2 id="Human_dog_horse">Human dog horse</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Night_vision&veaction=edit&section=6" title="Edit section: Human dog horse" class="mw-editsection-visualeditor"><span>edit</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Night_vision&action=edit&section=6" title="Edit section's source code: Human dog horse"><span>edit source</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul class="gallery mw-gallery-traditional"> <li class="gallerybox" style="width: 155px"> <div class="thumb" style="width: 150px; height: 150px;"><span typeof="mw:File"><a href="/wiki/File:Eye_iris.jpg" class="mw-file-description" title="Human pupils are round"><img alt="Human pupils are round" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Eye_iris.jpg/120px-Eye_iris.jpg" decoding="async" width="120" height="80" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Eye_iris.jpg/180px-Eye_iris.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/65/Eye_iris.jpg/240px-Eye_iris.jpg 2x" data-file-width="2788" data-file-height="1864" /></a></span></div> <div class="gallerytext">Human pupils are round</div> </li> <li class="gallerybox" style="width: 155px"> <div class="thumb" style="width: 150px; height: 150px;"><span typeof="mw:File"><a href="/wiki/File:Siberian_Husky_heterchromia_edit.jpg" class="mw-file-description" title="Dogs pupils are round"><img alt="Dogs pupils are round" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8d/Siberian_Husky_heterchromia_edit.jpg/120px-Siberian_Husky_heterchromia_edit.jpg" decoding="async" width="120" height="55" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8d/Siberian_Husky_heterchromia_edit.jpg/180px-Siberian_Husky_heterchromia_edit.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8d/Siberian_Husky_heterchromia_edit.jpg/240px-Siberian_Husky_heterchromia_edit.jpg 2x" data-file-width="1600" data-file-height="732" /></a></span></div> <div class="gallerytext">Dogs pupils are round</div> </li> <li class="gallerybox" style="width: 155px"> <div class="thumb" style="width: 150px; height: 150px;"><span typeof="mw:File"><a href="/wiki/File:Rokvitt_oga.jpg" class="mw-file-description" title="Horse pupils are horizontal ovals"><img alt="Horse pupils are horizontal ovals" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8c/Rokvitt_oga.jpg/120px-Rokvitt_oga.jpg" decoding="async" width="120" height="90" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8c/Rokvitt_oga.jpg/180px-Rokvitt_oga.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8c/Rokvitt_oga.jpg/240px-Rokvitt_oga.jpg 2x" data-file-width="500" data-file-height="375" /></a></span></div> <div class="gallerytext">Horse pupils are horizontal ovals</div> </li> </ul> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Netzhautlk-polarp.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a8/Netzhautlk-polarp.jpg/220px-Netzhautlk-polarp.jpg" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a8/Netzhautlk-polarp.jpg/330px-Netzhautlk-polarp.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a8/Netzhautlk-polarp.jpg/440px-Netzhautlk-polarp.jpg 2x" data-file-width="730" data-file-height="730" /></a><figcaption>Left eye field of view</figcaption></figure> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Night_vision&veaction=edit&section=7" title="Edit section: External links" class="mw-editsection-visualeditor"><span>edit</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Night_vision&action=edit&section=7" title="Edit section's source code: External links"><span>edit source</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Wikipedia: <a href="https://en.wikipedia.org/wiki/Eye" class="extiw" title="w:Eye">eye</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Questions">Questions</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Night_vision&veaction=edit&section=8" title="Edit section: Questions" class="mw-editsection-visualeditor"><span>edit</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Night_vision&action=edit&section=8" title="Edit section's source code: Questions"><span>edit source</span></a><span class="mw-editsection-bracket">]</span></span></div> <ol><li>Why is the US military not concerned about dyes on camouflage uniforms? Because the effect of these dyes occurs only when illuminated with black light, and for combat use artificial illumination has limited tactical advantage and greater tactical disadvantage.</li></ol> <ol><li>Does this lack of concern mean black light is not useful for SAR? Why? No, because for SAR black light illumination has more tactical advantages than disadvantages.</li></ol> <p><br /> </p> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Night_vision&veaction=edit&section=9" title="Edit section: References" class="mw-editsection-visualeditor"><span>edit</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Night_vision&action=edit&section=9" title="Edit section's source code: References"><span>edit source</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r2661605">.mw-parser-output .reflist{font-size:90%;margin-bottom:0.5em;list-style-type:decimal}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width reflist-columns-2"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><a href="#cite_ref-1">↑</a></span> <span class="reference-text">Wikipedia: <a href="https://en.wikipedia.org/wiki/Forward_looking_infrared" class="extiw" title="w:Forward looking infrared">Forward looking infrared</a></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><a href="#cite_ref-2">↑</a></span> <span class="reference-text">Wikipedia: <a href="https://en.wikipedia.org/wiki/Optical_brightener" class="extiw" title="w:Optical brightener">Optical brightener</a></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><a href="#cite_ref-3">↑</a></span> <span class="reference-text">Wikipedia: <a href="https://en.wikipedia.org/wiki/Fluorescence" class="extiw" title="w:Fluorescence">Fluorescence</a></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><a href="#cite_ref-4">↑</a></span> <span class="reference-text"><i><a rel="nofollow" class="external text" href="http://www.vandenberg.af.mil/news/story.asp?id=123065881">Optical brightners make ABUs dangerously easy to see</a></i>, Vandenberg Air Force Base, 24 August 2007</span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><a href="#cite_ref-5">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://archive.is/20121212202932/http://www.af.mil/news/story.asp?id=123099665">Airmen can use regular detergent on ABUs</a>, Air Force Link, 21 May 2008</span> </li> </ol></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; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikiversity.org/w/index.php?title=Night_vision&oldid=2415839">https://en.wikiversity.org/w/index.php?title=Night_vision&oldid=2415839</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Special:Categories" title="Special:Categories">Categories</a>: <ul><li><a href="/wiki/Category:Search_and_rescue" title="Category:Search and rescue">Search and rescue</a></li><li><a href="/wiki/Category:Freshly_started_resources" title="Category:Freshly started resources">Freshly started resources</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 17 August 2022, at 13:27.</li> <li id="footer-info-copyright">Text is available under the <a rel="nofollow" class="external text" href="//creativecommons.org/licenses/by-sa/4.0/">Creative Commons Attribution-ShareAlike License</a>; additional terms may apply. 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