Optical simulation of a plastic lens reflecting injection molding effects

The present work covers a new ray tracing method of an injection-molded plastic lens linked with CAE analysis of injection molding processes. The traditional ray tracing schemes have been based on the assumption that optical property of the lens is homogeneous throughout the entire volume. However, this assumption is quite unrealistic since material properties vary at every point due to injection molding effects. In order to consider non-homogeneous property of a lens, a modified ray tracing method is proposed in connection with finite element analysis of injection molding. Through the injection molding simulation, we can obtain the distribution of refractive indices of the lens. This information is then applied to the proposed ray tracing scheme based on finite element meshes. The effect of mold temperature is investigated through injection molding simulation, and the relevant optical quality is evaluated through the proposed ray tracing simulation.