This method involves coating LEDs of one color (mostly blue LEDs made of InGaN) with phosphors of different colors to form white light; the resultant LEDs are called phosphor-based or phosphor-converted white LEDs (pcLEDs). A fraction of the blue light undergoes the Stokes shift being transformed from shorter wavelengths to longer. Depending on the color of the original LED, phosphors of different colors can be employed. If several phosphor layers of distinct colors are applied, the emitted spectrum is broadened, effectively raising the color rendering index (CRI) value of a given LED. COUNT 5
QSN1 What method involves coating LEDs of one color with phosphors of different colors? ANS1 phosphor-converted white LEDs (pcLEDs) QSN2 In pcLEDs method, a fraction of what light is used? ANS2 blue QSN3 What shift does blue light undergo in the pcLEDs method? ANS3 Stokes QSN4 The different colors of phosphors that can be used is based on what? ANS4 the color of the original LED QSN5 What broadens the emitted spectrum in a pcLEDs method? ANS5 If several phosphor layers of distinct colors are applied