InGaN-based single-chip multicolor light-emitting diodes

A light-emitting diode (LED) driving technique to realize single-chip multicolor LEDs was proposed. The technique utilizes one of the characteristics of InGaN-based visible LEDs, the current-induced spectral blueshift. By applying pulsed current, which had two pulses of different amplitude in a cycle, to an InGaN single-quantum-well green LED, the light of two wavelengths corresponding to bluegreen and green was emitted from the same point, and the emission color of the LED was controlled continuously from bluegreen to green by adjusting only the pulse widths.