Led ismi, ingilizce Light Emitting Diode (I\u015f\u0131k Yayan Diyot) kelimelerinin ba\u015f harflerinden olu\u015fmaktad\u0131r.
\nBu \u0131\u015f\u0131kl\u0131 diyotlar, kullan\u0131\u015fl\u0131 ve pratik olmalar\u0131n\u0131n yan\u0131 s\u0131ra olduk\u00e7a ucuz olmalar\u0131 nedeniyle indikat\u00f6r (g\u00f6sterge) olarak di\u011fer tip lambalar\u0131n yerini alm\u0131\u015flard\u0131r. Piyasada \u00e7ok de\u011fi\u015fik \u015fekil, ebad, renk ve fiyatta LED bulundu\u011fundan herhangi bir devrede ne tip bir led kullan\u0131labilece\u011fi, genellikle bir soru i\u015fareti olu\u015fturmaktad\u0131r. Burada LED ‘ler ile ilgili baz\u0131 ayd\u0131nlat\u0131c\u0131 bilgi verilmeye \u00e7al\u0131\u015f\u0131lm\u0131\u015ft\u0131r. B\u00f6ylece LED se\u00e7iminde kolayl\u0131k sa\u011flayaca\u011f\u0131n\u0131 umuyoruz.<\/p>\n
I\u015f\u0131k yayan diyotlar, ilk olarak 1954 y\u0131l\u0131nda bulunmu\u015ftur. Galyum Fosfat (GaP) ile yap\u0131lm\u0131\u015f bir diyotun, iletim y\u00f6n\u00fcnde ak\u0131m ge\u00e7irildi\u011finde k\u0131rm\u0131z\u0131 bir \u0131\u015f\u0131k yayd\u0131\u011f\u0131 farkedilmi\u015ftir. B\u00f6ylece bir yar\u0131iletken \u0131\u015f\u0131k kayna\u011f\u0131 ke\u015ffedimi\u015ftir, ancak yar\u0131iletkenlerdeki \u0131\u015f\u0131k yay\u0131m\u0131n\u0131n fizi\u011fi pek anla\u015f\u0131lamad\u0131\u011f\u0131 ve seri \u00fcretim i\u00e7in yeterli teknolojik d\u00fczeye eri\u015filemedi\u011fi i\u00e7in led ‘ler yak\u0131n zamana kadar pek pop\u00fcler olamam\u0131\u015flard\u0131r. Bu sorunlar\u0131n a\u015f\u0131lmas\u0131dan sonra ledler inan\u0131lmaz bir \u015fekilde kendilerine \u00e7ok geni\u015f bir uygulama alan\u0131 bulmu\u015flard\u0131r.<\/p>\n
\u0130lk led ‘ler TO-18 transist\u00f6r k\u0131l\u0131f\u0131 i\u00e7erisinde ve u\u00e7lar\u0131 \u015feffaf plastik mercek \u015feklindeydi. Mevcut \u0131\u015f\u0131k rengi sadece k\u0131rm\u0131z\u0131yd\u0131 ve verim, yani uygulanan g\u00fcce kar\u015f\u0131 elde edilen \u0131\u015f\u0131k miktar\u0131 son derece yetersizdi.
\nZamanla yar\u0131iletkenlerde yay\u0131lan \u0131\u015f\u0131k ile ilgili teorik bilgiler geli\u015ftik\u00e7e GaP diyotlar\u0131ndan yay\u0131lan k\u0131rm\u0131z\u0131 \u0131\u015f\u0131\u011fa, bu yar\u0131iletken madde i\u00e7erisinde bulunan \u00e7inko ve oksijen atomlar\u0131n\u0131n sayesinde olu\u015ftu\u011fu anla\u015f\u0131lm\u0131\u015ft\u0131r. Daha saf GaP maddesiyle yap\u0131lan Led ‘lerin, bu sefer ye\u015fil bir \u0131\u015f\u0131k yayd\u0131klar\u0131 g\u00f6zlenmi\u015ftir. Daha sonra ise \u00e7ok \u00e7e\u015fitli yar\u0131iletken maddeler denenmi\u015f ve kullan\u0131lm\u0131\u015ft\u0131r. G\u00fcn\u00fcm\u00fczde ise en \u00e7ok kullan\u0131lan madde ise Galyum Arsenit Fosfat (GaAsP) ‘t\u0131r. Bu maddenin avantaj\u0131, arsenik ve fosfat oranlar\u0131n\u0131 de\u011fi\u015ftirmek suretiyle infraruj (infra-red) ile ye\u015fil aras\u0131nda pek \u00e7ok renk elde edilebilmesidir.<\/p>\n
G\u00fcn\u00fcm\u00fczde kullan\u0131lan Led ‘ler aras\u0131nda en pop\u00fcleri, k\u0131rm\u0131z\u0131 olan\u0131d\u0131r. Bu tip led ‘ler GaAs0,6P0,4 form\u00fcl\u00fc ile yap\u0131lmaktad\u0131r. Yani As : P oran\u0131 6 : 4 ‘t\u00fcr. K\u0131rm\u0131z\u0131 Led ‘ler yap\u0131m\u0131 en kolay, dolay\u0131s\u0131yla en ucuz, bunun yan\u0131nda da verimi en y\u00fcksek olanlar\u0131d\u0131r. Ye\u015fil Led ‘ler ise verimi en d\u00fc\u015f\u00fck LED \u00e7e\u015fididir. Ancak bu dezavantaj\u0131 insan g\u00f6z\u00fcn\u00fcn ye\u015file k\u0131rm\u0131z\u0131dan daha hassas olmas\u0131 nedeniyle ortadan kalkmaktad\u0131r.<\/p>\n
Herhangi bir uygulama i\u00e7in renk se\u00e7imi yaparken baz\u0131 hususlara dikkat edilmelidir. K\u0131rm\u0131z\u0131, genellikle ikaz devreleri i\u00e7in tercih edilmelidir. Ancak sar\u0131, turuncu ve ye\u015fil Led ‘ler, di\u011fer baz\u0131 ama\u00e7lar i\u00e7in daha estetik olabilmektedir.<\/p>\n
Led se\u00e7iminde verim \u00f6nemli bir fakt\u00f6rd\u00fcr. Ye\u015fil ve sar\u0131 Led ‘lerin verimleri, k\u0131rm\u0131z\u0131 Led ‘lere nazaran daha d\u00fc\u015f\u00fckt\u00fcr. Ancak pille \u00e7al\u0131\u015fan k\u00fc\u00e7\u00fck cihazlar d\u0131\u015f\u0131nda bu durum bir problem te\u015fkil etmemekte, verim d\u00fc\u015f\u00fckl\u00fc\u011f\u00fc biraz daha fazla g\u00fc\u00e7 tatbikiyle ortadan kalkmaktad\u0131r. Ye\u015fil bir Led ‘den k\u0131rm\u0131z\u0131 Led ‘lerdeki kadar \u0131\u015f\u0131k elde edebilmek i\u00e7in iki kat\u0131na yak\u0131n LED ak\u0131m\u0131na gereksinim duyulmaktad\u0131r. Ancak \u015febekeden beslenen cihazlar i\u00e7in bu bir sak\u0131nca te\u015fkil etmemektedir.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":" Led ismi, ingilizce Light Emitting Diode (I\u015f\u0131k Yayan Diyot) kelimelerinin ba\u015f harflerinden olu\u015fmaktad\u0131r. Bu \u0131\u015f\u0131kl\u0131…<\/p>\n","protected":false},"author":1,"featured_media":2585,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[1011,842,257,1012,1010],"aioseo_notices":[],"featured_image_urls":{"full":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false],"thumbnail":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images-150x150.jpg",150,150,true],"medium":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images-300x150.jpg",300,150,true],"medium_large":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false],"large":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false],"1536x1536":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false],"2048x2048":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false],"covernews-slider-full":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false],"covernews-slider-center":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false],"covernews-featured":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false],"covernews-medium":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false],"covernews-medium-square":["https:\/\/devrearsivi.com\/wp-content\/uploads\/2014\/06\/images.jpg",316,159,false]},"author_info":{"display_name":"Ferhat \u00c7elik","author_link":"https:\/\/devrearsivi.com\/author\/94ferhat\/"},"category_info":"Malzeme Bilgisi<\/a>","tag_info":"Malzeme Bilgisi","comment_count":"2","_links":{"self":[{"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/posts\/2584"}],"collection":[{"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/comments?post=2584"}],"version-history":[{"count":1,"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/posts\/2584\/revisions"}],"predecessor-version":[{"id":2586,"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/posts\/2584\/revisions\/2586"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/media\/2585"}],"wp:attachment":[{"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/media?parent=2584"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/categories?post=2584"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devrearsivi.com\/wp-json\/wp\/v2\/tags?post=2584"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}