Abstract
Injection-molded lenses have been widely employed for 3 C products more recently. In this paper, 3D CAE flow analysis embedded with DOE methods have been adopted for studying lenses molded with cyclic-olefin-copolymers together with residual birefringence measurements. In addition, thermal annealing experiments have been performed on the relaxation effects on thermal history for further studies. Results have shown that shear stresses as birefringence are contributed by melt temperature and injection speed during filling; while, dimensional errors on optical surfaces of lenses have been influenced by melt temperature and holding pressure during the packing and cooling.