led、led顯示屏的發(fā)展歷史、發(fā)展意義及前景畢業(yè)論文-全文預覽
【正文】 LED，隨即又制造出能產(chǎn)生高強度的綠光和藍光銦氮鎵 Led。 80 年代早期到中期對砷化鎵磷化鋁的使用使得第一代高亮度的 LED 的誕生，先是紅色，接著就是黃色，最后為綠色。 LED 采用雙層磷化鎵蕊片（一個紅色另一個是綠色）能夠發(fā)出黃色光。據(jù)說在早期的試驗中， LED 需要放置在液化氮里，更需要進一步的操作與突破以便能高效率的在室溫下工作。再一次因發(fā)光暗淡而停止。然而照明需用的白色光 LED 僅在近年才發(fā)展起來 。這種通過藍光 LED 得到白光的方法，構(gòu)造簡單、成本低廉、技術(shù)成熟度高，因此運用最多。 GaN 芯片發(fā)藍光（ λp=465nm， Wd=30nm），高溫燒結(jié)制成的含 Ce3+的 YAG 熒光粉受此藍光激發(fā)后發(fā)出黃色光射，峰值 550nm。 汽車信號燈也是 LED光源應用的重要領(lǐng)域。 最初 LED 用作儀器儀表的指示光源，后來各種光色的 LED 在交通信號燈和大面積顯示屏中得到了廣泛應用，產(chǎn)生了很好的經(jīng)濟效益和社會效益。在某些半導體材料的 PN結(jié)中，注入的少數(shù)載流子與多數(shù)載流子復合時會把多余的能量以光的形式釋放出來，從而把電能直接轉(zhuǎn)換為光能。 with the progress of technology, the lightemitting diodes have been widely used in monitors, television lighting decoration and can only go in one direction conduction (electricity), a positive bias is called (forward bias), when the current flows, electron and hole in the posite and emit monochromatic light, this is called electroluminescence effect, and the wavelength of light, color and semiconductor materials with the incorporation of impurities in the using the. Has the advantages of high efficiency, long service life, not easy to be damaged, switch has the advantages of high reliability, high speed, less than the traditional light source. The luminous efficiency of white LED, in recent years there have been significantly improved, at the same time, in every thousand lumens of the purchase price, but also because of investment firms peting, dropped obviously. Although more and more people are using LED lighting for office furniture, decoration, signs, even street lamp uses, but technically, LED in the photoelectric conversion efficiency (the ratio of effective illumination electricity) remains below the fluorescent lamp model, is the country after the development of civilian39。具有效率高、壽命長、不易破損、開關(guān)速度高、高可靠性等傳統(tǒng)光源不及的優(yōu)點。安徽蚌埠機電技師學院應用電子 技術(shù)專業(yè) 畢業(yè)論文 第 1 頁 共 12 頁 目 錄 摘要 ??????????????????????????? 2 1 LED概述 ?????? ??? .??????????????? 3 LED發(fā)展歷史介紹 ??? ????? ??? ?????? 4 LED 的發(fā)展前景 ????? .????????? 5 2 LED 顯示屏概述 ????????????????????? 6 LED 顯示屏發(fā)展經(jīng)歷了三個階 ??? ???????? 7 我國 LED 顯示屏發(fā)展現(xiàn)狀 ????????????? 9 3結(jié)束語 ????? ???????????????????? 11 致謝 ?????????????????????????? 12 參考文獻 ??????????????? ???????? 12 安徽蚌埠機電技師學院應用電子 技術(shù)專業(yè) 畢業(yè)論文 第 2 頁 共 12 頁 LED、 LED 顯示 屏 的發(fā)展歷史 、 發(fā)展意義及前景 摘要 發(fā)光二極管（英語： LightEmitting Diode，簡稱 LED） 是一種能發(fā)光的半導體電子元件。 LED 只能往一個方向?qū)ǎㄍ姡凶髡蚱茫ㄕ蚱珘海?，當電流流過時，電子與空穴在其內(nèi)復合而發(fā)出單色光，這叫電致發(fā)光效應，而光線
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