**3.2 Blue LD chip and color conversion phosphors**

White light can be generated by using a blue LD to excite remote phosphor film composed of green and red-emitting phosphors. The mixture of the residual blue light and emitted red and green lights forms a white light. The green and red-emitting phosphors can have broad emission wavelength ranges, which helps generate high CRI white light. An enormous loss of energy occurs in converting the blue light into green and red through the phosphors.
