Police laser blinding devices are primarily used in the field of security. A human target will lose vision temporarily when exposed to the green laser emitted by the device because the human eye is sensitive to the 532-nm green laser. The laser light must cover the target human body as much as possible to improve utilization of the laser. This subject obtains video from the camera and detects pedestrian targets through a video processing system based on digital signal processing (DSP) using the Gentle Adaboost algorithm. The detection results include the size and location of the pedestrian targets. According to the size of the pedestrian, a single chip microcomputer control circuit controls the laser lens to focus on pedestrian targets automatically to accommodate pedestrian targets.