Zifukwa za Kutentha kwa Kutentha kwa LED
Monga momwe zimakhalira ndi magetsi ochiritsira, ma semiconductor emitting diode (ma LED) amatulutsanso kutentha panthawi yogwira ntchito, kutengera mphamvu zonse zowala. Pansi pa mphamvu yamagetsi yomwe imagwiritsidwa ntchito, ma radiation a ma elekitironi ndi mabowo amalumikizananso kuti apange electroluminescence, ndipo kuwala komwe kumatuluka pafupi ndi mphambano ya PN kumafunika kudutsa pakatikati pa semiconductor ndi kulongedza sing'anga ya chip yokha kuti ifike kunja (mpweya). Kuthekera kokwanira kwa jakisoni wamakono, kuwala kwamphamvu kwa radiation luminescence quantum, kugwiritsa ntchito bwino kwa chip kunja kwa kuwala, ndi zina zotero, chomaliza ndi 30-40% yokha ya mphamvu yolowera mu mphamvu yowunikira, ndipo 60-70% yotsalira ya mphamvu zake makamaka imapezeka m'malo opanda mphamvu. Ma radiation ovuta mawonekedwe a kutentha kwa dontho-matrix vibration.
Kuwonjezeka kwa kutentha kwa chip kudzakulitsa zovuta zosagwiritsa ntchito ma radiation, ndikuchepetsanso mphamvu yowala. Chifukwa anthu amaganiza kuti ma LED amphamvu kwambiri alibe kutentha, kwenikweni, amatero. Kutentha kwambiri kumayambitsa mavuto ambiri pakagwiritsidwe ntchito. Kuonjezera apo, anthu ambiri omwe amagwiritsa ntchito ma LED amphamvu kwambiri kwa nthawi yoyamba ndipo samamvetsa momwe angathetsere bwino mavuto a kutentha, kupanga kudalirika kwa kupanga kukhala vuto lalikulu. Ndiye nayi mafunso omwe tiyenera kuganizira: Kodi ma LED ali ndi kutentha kulikonse? Zingathe kutentha bwanji? Kodi ma LED amatulutsa kutentha kochuluka bwanji?
Pansi pa magetsi akutsogolo a LED, ma elekitironi amapeza mphamvu kuchokera kumagetsi. Pansi pa kuyendetsa magetsi, magetsi a PN akugonjetsedwa, ndipo kusintha kuchokera ku dera la N kupita ku P dera kumachitika. Ma elekitironi awa amalumikizananso ndi mabowo omwe ali m'chigawo cha P. Popeza kuti ma elekitironi aulere omwe amalowa m'chigawo cha P ali ndi mphamvu zambiri kuposa ma electron a valence m'chigawo cha P, ma electron amabwerera ku mphamvu yochepa panthawi yogwirizanitsa, ndipo mphamvu yowonjezereka imatulutsidwa mu mawonekedwe a photons. Kutalika kwa mawonekedwe a photon otulutsidwa kumakhudzana ndi kusiyana kwa mphamvu Mwachitsanzo. Zitha kuwoneka kuti malo opangira kuwala ali pafupi ndi mphambano ya PN, ndipo kutuluka kwa kuwala ndi zotsatira za mphamvu zomwe zimatulutsidwa ndi kuyanjananso kwa ma electron ndi mabowo. Mu semiconductor diode, ma elekitironi amakumana ndi kukana paulendo wonse kuchokera ku semiconductor zone kupita ku semiconductor zone. Mwachidule kuchokera pa mfundoyi, mawonekedwe a thupi la semiconductor diode amangochokera ku mfundo, chiwerengero cha ma elekitironi otulutsidwa kuchokera ku electrode yolakwika ndi ma electron omwe amabwerera ku electrode yabwino ya semiconductor diode ndi ofanana. Wamba diode, pamene elekitironi-bowo awiri recombination kumachitika, chifukwa cha kusiyana mphamvu mlingo Mwachitsanzo, anamasulidwa photon sipekitiramu si mu osiyanasiyana looneka.
Panjira mkati mwa diode, ma elekitironi amadya mphamvu chifukwa cha kukana. Mphamvu zomwe zimagwiritsidwa ntchito zimagwirizana ndi malamulo oyambira zamagetsi:
P = I2 R = I2 (RN + + RP) + IVTH
Zindikirani: RN ndiye kukana kwa thupi kwa N zone
VTH ndi mphamvu yamagetsi yamagetsi ya PN
RP ndiye kukana kwakukulu kwa dera la P
Kutentha kopangidwa ndi mphamvu yogwiritsidwa ntchito ndi:
Q = Pt
Kumene: t ndi nthawi yomwe diode imalimbikitsidwa.
M'malo mwake, LED ikadali diode ya semiconductor. Choncho, pamene LED ikugwira ntchito kutsogolo, ntchito yake ikugwirizana ndi zomwe tafotokozazi. Mphamvu yamagetsi yomwe imawononga ndi:
P LED = U LED × Ine LED
Kumene: U LED ndiye magetsi akutsogolo kudutsa gwero la kuwala kwa LED
I LED ndiyomwe imayenda kudzera mu LED
Mphamvu yamagetsi yomwe imagwiritsidwa ntchito imasinthidwa kukhala kutentha ndikumasulidwa:
Q＝P LED × t
Zindikirani: t ndiye mphamvu pa nthawi
Ndipotu, mphamvu yomwe imatulutsidwa pamene electron ikuphatikizanso ndi dzenje m'chigawo cha P sichiperekedwa mwachindunji ndi magetsi akunja, koma chifukwa electron ili m'dera la N, pamene palibe magetsi akunja, mphamvu yake ndi yapamwamba. kuposa dera la P. Mulingo wa elekitironi wa Valence ndi wapamwamba kuposa mwachitsanzo. Ikafika kudera la P ndikuphatikizanso ndi mabowo kuti ikhale ma elekitironi a valence m'chigawo cha P, imamasula mphamvu zambiri. Kukula kwa Eg kumatsimikiziridwa ndi zinthu zomwezo ndipo ziribe kanthu kochita ndi munda wamagetsi wakunja. Ntchito yamagetsi akunja kwa electron ndikukankhira kuti isunthe molunjika ndikugonjetsa gawo la PN mphambano.
Kuchuluka kwa kutentha komwe kumapangidwa ndi LED sikukhudzana ndi kuwala kwa kuwala; palibe mgwirizano pakati pa kuchuluka kwa mphamvu zamagetsi zomwe zimapanga kuwala, ndipo gawo lotsala la mphamvu zamagetsi limatulutsa kutentha. Kupyolera mu kumvetsa mfundo za kutulutsa kutentha, kukana kutentha ndi kutentha kwapakati pa ma LED amphamvu kwambiri komanso kutengeka kwa mafomu ofotokozera ndi kuyeza kwa kutentha kwa kutentha, tikhoza kuphunzira momwe ma CD ake amapangidwira, kuyesa ndi kugwiritsa ntchito mankhwala a ma LED amphamvu kwambiri. Tiyenera kuzindikira kuti kasamalidwe ka kutentha ndi nkhani yofunika kwambiri pakalipano ya kuwala kocheperako kwa zinthu za LED. Kuwongolera bwino kowala kuti muchepetse kutulutsa mphamvu za kutentha ndiko kumunsi kwa ketulo. Izi zimafuna kupanga chip, kuyika kwa LED ndi chitukuko cha ntchito. Kupita patsogolo kwaukadaulo m'mbali zonse.
