Binciken manyan hanyoyin fasaha don fararen LEDs don haske
Nau'in Farin LED: Babban hanyoyin fasaha don fararen LEDs don haske sune: 1 blue LED + nau'in phosphor; 2RGB LED nau'in; 3 ultraviolet LED + nau'in phosphor
1. Blue-LED guntu + rawaya-kore phosphor nau'in ya hada da Multi-launi phosphor wanda aka samu
Layin phosphor mai launin rawaya-kore yana ɗaukar wani ɓangare na hasken shuɗi na guntu na LED don samar da haske mai haske, ɗayan ɓangaren hasken shuɗi daga guntuwar LED yana watsa Layer phosphor kuma yana haɗuwa tare da hasken rawaya-kore wanda phosphor ke fitarwa a wurare daban-daban a cikin sararin samaniya, kuma hasken ja, kore da shuɗi yana haɗuwa don samar da farin haske; Ta wannan hanyar, ƙimar mafi girman ka'idar ingancin canjin photoluminescence na ɗayan ƙimar ƙimar waje ba zai wuce 75% ba; kuma adadin cirewar guntu luminescence zai iya kaiwa kusan 70% kawai, don haka a ka'idar, hasken shuɗi fari ne. Hasken haske na LED ba zai wuce 340 Lm/W ba, CREE ya kai 303Lm/W a cikin shekarun da suka gabata, kuma yana da daraja yin bikin idan sakamakon gwajin ya kasance daidai.
2, Red, kore da blue uku na farko launi hade RGB LED irin ciki har da RGBW-LED irin, da dai sauransu.
R-LED (ja) + G-LED (kore) + B- LED (blue) LEDs guda uku an haɗa su, kuma ja, koren haske da shuɗi na launuka na farko guda uku ana gauraye su kai tsaye a sararin samaniya don zama farin haske. Domin samar da farin haske mai inganci ta wannan hanyar, da farko, LEDs masu launuka daban-daban, musamman koren ledoji, dole ne su kasance tushen haske mai inganci, wanda kusan kashi 69% ana iya gani daga “farin hasken wuta” a halin yanzu. Ingantattun LEDs masu launin shuɗi da ja ya kasance mai girma sosai, kuma ƙimar ƙididdigewa na ciki ya wuce 90% da 95%, bi da bi, amma ƙimar ƙididdige ƙididdigewa na cikin koren LEDs yana da nisa a baya. Lamarin da cewa irin wannan hasken koren LED na tushen GaN ba shi da inganci ana kiransa "rabin hasken kore." Babban dalili shi ne cewa koren LED bai sami nasa kayan epitaxial ba. Abubuwan da ake da su na phosphorous-arsenic nitride suna da ƙarancin inganci a cikin kewayon bakan launin rawaya-kore, kuma ana amfani da haske ja ko shuɗi mai haske epitaxial abu don yin koren LED. A ƙananan yanayi mai yawa na yanzu, koren LEDs suna da inganci mafi girma fiye da shuɗi + phosphor koren haske saboda babu asarar canjin phosphor. An ba da rahoton cewa ingancin haske ya kai 291 Lm / W a 1 mA. Duk da haka, tasirin haske na hasken koren da ke haifar da tasirin Droop ya ragu sosai a babban halin yanzu, kuma lokacin da yawan ƙarfin halin yanzu ya karu, tasirin haske yana da tasiri. saukar da sauri. A halin yanzu na 350 mA, ingantaccen ingantaccen haske shine 108 Lm/W, kuma ƙarƙashin yanayin 1 A, ingantaccen ingantaccen haske ya faɗi zuwa 66 Lm/W.
Ga rukuni na III phosphides, fitar da haske zuwa koren band ya zama babban shinge ga tsarin kayan. Canza abun da ke ciki na AlInGaP yana sa ya haskaka kore maimakon ja, lemu ko rawaya-wanda ke haifar da rashin isassun tsarewar jigilar kaya saboda ƙarancin tazarar kuzarin tsarin kayan, yana kawar da ingantaccen haɗewar haɗewa.
Sabanin haka, rukunin nitrides na rukuni na uku sun fi wahalar cimmawa, amma wahalar ba ta yuwuwa. Tare da wannan tsarin, abubuwa guda biyu waɗanda ke haifar da raguwar ingancin aiki saboda haɓakar haske a cikin koren band sune: ƙimar ƙima na waje da lalata ingancin wutar lantarki. Rage ƙimar ƙimar ƙididdigewa na waje yana haifar da gaskiyar cewa koren LED yana da babban ƙarfin wutar lantarki na GaN, wanda ke haifar da saurin jujjuya wutar lantarki. Rashin hasara na biyu shine cewa koren LED yana raguwa yayin da yawan alluran yanzu ke ƙaruwa, wanda tasirin faɗuwa ya kama. Har ila yau, tasirin Droop yana bayyana a cikin ledojin shuɗi, amma yana da mahimmanci a cikin koren LEDs, yana haifar da ƙananan igiyoyin aiki. Duk da haka, akwai dalilai da yawa na dalilin faɗuwar tasirin, ba wai kawai mahallin Auger ba, har ma da rashin wuri, ambaliya mai ɗaukar kaya ko ɗigon lantarki. Ƙarshen yana haɓaka ta wurin babban ƙarfin lantarki na ciki.
Sabili da haka, hanyar da za a inganta ingantaccen haske na LED LEDs: a gefe guda, yadda za a rage tasirin Droop a ƙarƙashin yanayin kayan abu na epitaxial na yanzu don inganta ingantaccen haske; al'amari na biyu, da photoluminescence hira na blue LED da koren phosphor na fitar da koren haske, Hanyar iya samun high-inganci koren haske, da kuma a ka'idar iya cimma mafi girma fiye da halin yanzu farin haske sakamako, wanda nasa ne maras maras lokaci koren haske, kuma tsaftar launi da ke haifar da faɗaɗawar gani yana raguwa, wanda ba shi da daɗi don nunawa, amma ga talakawa Babu matsala tare da haskakawa. Tasirin hasken kore da aka samu ta wannan hanya yana da yuwuwar fiye da 340 Lm/W, amma har yanzu bai wuce 340 Lm/W ba bayan haɗa farin haske. Na uku, ci gaba da bincike da gano kayan aikin epitaxial, kawai Ta wannan hanyar, akwai bege cewa ta hanyar samun ƙarin haske mai haske fiye da 340 Lm / w, hasken farin da aka haɗe da ja, kore da blue uku LEDs masu launi na farko na iya zama. sama da iyakar ingancin haske na nau'in guntu mai launin shuɗi fari LED 340 Lm / W.
3.UV LED guntu + uku na farko launi phosphor haske
Babban lahani na waɗannan fararen LEDs guda biyu na sama shine rashin daidaituwa na rarraba sararin samaniya na haske da chromaticity. Hasken ultraviolet baya gani ga idon ɗan adam. Saboda haka, bayan hasken ultraviolet ya fito daga guntu, sai ya zama nau'in phosphor uku na farko na nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i). Wannan ita ce babbar fa'idarsa, kamar fitilun fitilu na gargajiya, ba shi da rashin daidaituwar launi na sarari. Koyaya, tasirin haske na ka'idar ultraviolet guntu nau'in farin LED ba zai iya zama sama da ƙimar ka'idar shuɗin guntu nau'in farin haske ba, kuma ba shi da yuwuwa ya zama mafi girma fiye da ƙimar ƙimar nau'in farin haske na RGB. Koyaya, ta hanyar haɓaka phosphor masu inganci masu inganci waɗanda suka dace da haɓakar hasken ultraviolet cewa yana yiwuwa a sami nau'ikan fararen fararen haske na ultraviolet waɗanda ke kusa ko ma mafi inganci fiye da farar LED guda biyu na yanzu. Mafi kusa da hasken ultraviolet LEDs masu launin shuɗi, yuwuwar mafi girman matsakaicin matsakaicin raƙuman ruwa da gajeriyar ultraviolet nau'in farin LEDs, mafi yiwuwa ba zai yiwu ba.