Title :
Phosphor-Free White Light From InGaN Blue and Green Light-Emitting Diode Chips Covered With Semiconductor-Conversion AlGaInP Epilayer
Author :
Horng, Ray-Hua ; Han, Pin ; Wuu, Dong-Sing
Author_Institution :
Inst. of Precision Eng., Nat. Chung Hsing Univ., Taichung
fDate :
7/1/2008 12:00:00 AM
Abstract :
A phosphor-free white lamp was fabricated using the InGaN-based blue and green light-emitting diode (LED) chips covered with semiconductor-conversion layer AlGalnP. The lamp can provide three bands: a 460-nm blue emission coming from the blue LED, a 555-nm green emission coming from the green LED, and 630-nm red emission coming from the excited AlGalnP epilayer. As 50 mA was injected into the white lamp at room temperature, the chromaticity coordinates and correlated color temperature (TC) are (0.338,0.335) and 5348 K, respectively. By separating injection current into blue and green LED chips, TC of lamp can be tuned from about 4000 K to 5400 K.
Keywords :
III-V semiconductors; LED lamps; aluminium compounds; colour; gallium compounds; indium compounds; optical fabrication; semiconductor epitaxial layers; AlGaInP; InGaN; chromaticity coordinates; correlated color temperature; current 50 mA; injection current; light-emitting diode chips; phosphor-free white light lamp fabrication; semiconductor-conversion epilayer; temperature 293 K to 298 K; temperature 5348 K; wavelength 460 nm; wavelength 555 nm; wavelength 630 nm; Commercialization; Light emitting diodes; Luminescence; Phosphors; Power generation; Recycling; Resins; Stability; Temperature; Voltage control; AlGaInP; InGaN; chromaticity coordinates; correlated color temperature; light-emitting diode (LED); phosphor-free white lamp;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2008.924882
