The polygonal mirror-flat rotating-vibrating mirror laser scanner system is designed for PAL standard TV signal. The polygonal mirror has 40 facets and its rotating speed is ω=390.625 r/s. An analysis solution is obtained for horizontal scanning velocity of laser point on the screen. Based on the solution, it is found that exposure amount at the beginning (or end) of horizontal scanning line is 97.7% of that at the middle time of 32 μs.