A lighting system for grating light modulator based on LED light source is designed.The system is composed of free form surface TIR lens,light pipe and condensing lens,which are used as primary elements to improve the utility rate of luminous energy of LED and realize optical uniformity.The simulation results show that the utility rate of luminous energy is 78.7%,and the optical uniformity is 85%,which are consistent with the experimental results.It shows that the optimized lighting system for the grating l...