**3.1 Multiple LD's chips**

White light can be generated by mixing light from three individual (red, green, and blue) LDs. The luminous efficacy of generated white light is relatively higher because of the absence of color conversion phosphors and quantum deficits. Color variations with temperature can be observed because each LD's wavelength shift may differ with temperature changing. Because multiple LDs are used in this scheme, it is relatively expensive and complex.
