In the thesis, we design an optical system to meet the ECE regulation for the automobile low beam. In the optical system, we first design the arrangement of the LEDs and using a compound parabolic concentractor to serve as the first optics, which is to increase light extraction efficiency and enlarge the light pattern with keeping the etendue. We also design an imaging lens with an asymmetric structure to increase the contrast of the light pattern. We fabricate the design optical system and the comparison between the simulation and measurement is made. Finally, we analyze the alignment tolerance of the optical system.