摘要： An optimization method is proposed to improve the image quality of dynamic patterns in this paper. In order to obtain parallel emergent beam of high quality, aspheric microlens array is used in the optical system. Besides, an analytical model of the substrate and a single aspheric lens of MLA is presented based on the principle of ray tracing which is used in optical design for virtually tracing rays through an optical system. Moreover, how do the parameters influence the image quality is analyzed and the relationship between the conic constant and the divergence angle of emergent beam is derived. Preliminary optimization results with a second order aspheric lens are compared with the simulation results obtained by ZEMAX. The ray tracing method in this article helps improve the image quality of dynamic patterns and has the potential to be used in designing aspheric surface because it offers a way to improve the parallel rays and optimize the parameters of the optical system.