Headlight optical increasingly stringent regulatory requirements, modeling lamp shell gap also increased, from the early iron with glass reflector lamp shells evolved to now most of the lamp housing are using the PC as the main material. PC lamp shell has good strength , good light transmission and can be used with a large gap between headlight shape, etc., can be widely used lights to use, but a large gap between modeling led lamp shell surface is curved, when the mirror projection lamp shell elapsed without refraction stable, resulting in optical light points NG, this paper will discuss how to change the gradient type to use flesh shell allows the lamp reflector optical radiation through refracted light shell is stable thereby allowing optical instability lower. In this paper, UG SHIP instance validation two cars in the car with light point instability and using a gradient-type lamp shell after the flesh in the light distribution point so let stabilize.