A projection display module with compact size, low power consumption, and high resolution is key for augmented-reality glasses. To reduce the power consumption of the projection system, a silicon-based liquid-crystal projection system with dynamic illumination based on laser-beam scanning is designed. The system adopts a front-illumination architecture to realize spatial conversion between the laser-beam scanning angle and the imaging position of the spatial light modulator by multiplexing lenses. Additionally, it realizes 638 partitions in a 30°×40° field of view. By modeling the laser illumination intensity of individual partitions and simulating the dynamic illumination light-field distribution under different display scenarios, a partitioned illumination model of laser-beam scanning is established. Simulation results show that the dynamic illumination of laser-beam scanning can reduce lighting power consumption to less than 10% of power consumed by a non-dynamic illumination system in typical application scenarios of augmented reality, such as information prompting and navigation.