Abstract: In order to meet the demand for high pixels, miniaturization and without stray light of a modern mobile phone lens, a three-unit 5106 pixel optical system based on CODEV software was designed by optical plastic aspherical technology and Monte Carlo ray tracing method. Stray light was analyzed based on LightTools software. After theoretical analysis and experimental verification, the results show that the F number of lens is 2.6, the full field of view angle is 72.9, the total length of system is 3.1mm. Performance test results of the final assembled products meet design requirements and have no unacceptable stray light.