Diode lasers are often used as the light source of LiDAR for their high energy conversion efficiency, small size and good reliability. A novel collimator based on integrated aspheric cylindrical lens are proposed, which have different surface types in two surfaces, and it could collimate the diode laser in both directions. According to Fermat′s principle and beam expanding collimation theory, the surface parameters were determined preliminarily. The optical system of the light source projection was completed, which was optimized with the minimum spot radius and maximum luminous flux as the goals and the MEMS scanning mirror size as the limiting factor. Results show that the divergence angle in the meridional direction is 2 mrad, and the divergence angle in the sagittal direction is 9.6 mrad. The collimation effect is close to the average angular resolution of MEMS-LiDAR in the market, the lens volume is 10×10×24 mm3, the total length of the transmitter system is 40 mm, and the luminous rate of the system is 98.6%. It meets the requirements of MEMS-LiDAR for the collimation of the light source, the integration degree and stability of the transmitter system.