Efficiency of LEDs: Fabrication and Comparison

This lecture delves into the efficiency of LEDs, focusing on light extraction efficiency, optical output power, and wall-plug efficiency. It covers the eye sensitivity function, luminous flux, luminous efficacy, and efficiency comparison with alternative light sources. The discussion extends to LED fabrication, particularly blue LEDs, crucial for white LED realization. The lecture emphasizes the importance of the color rendering index in LED efficiency and introduces concepts like external quantum efficiency and power efficiency. Various techniques to improve LED efficiency, such as ThinGaN principle and resonant cavity LEDs, are explored. The lecture concludes with a historical perspective on white light sources and the growth potential of LEDs in general lighting.