Page 18 - Demo PravySoft Ezine
P. 18
Solar cell Materials in detail ....................... 290
LED ................................................ 294
Introduction .............................................. 294
Luminescence ............................................ 294
i. Photoluminescence ................................................... 295
ii. Cathodoluminescence ............................................... 295
iii. Radioluminescence .................................................... 295
iv. Electroluminescence.................................................. 295
Radiative transitions .................................. 296
pn junction LEDs ........................................ 298
PravySoft Ezine demo
PravySoft Ezine demo
Double heterostructure LED ....................... 300
LED line width ............................................ 303
LED materials ............................................. 307
LED efficiency ............................................ 311
i. Internal quantum efficiency (ηin) ............................... 312
ii. External quantum efficiency (ηext): ............................ 312
iii. Power efficiency (ηp).................................................. 313
Organic LEDs .............................................. 313
LCD ................................................ 317
