According to the practical solder paste printing inspection of PCB, digital fringe projector design used 0.45 WXGA DMD chip was performed in this paper. The design adopted LED as light source, and combined with lens array for evenness illumination. In order to reduce the influence of nonuniform fringe on inspection results caused by triangular relationship of projection, double telecentric optical configuration was used for imaging DMD-generating fringe on defected surface. The minimal inspection area of projector can reach 1mm2. Simulation results show that illumination evenness of the digital fringe projector on defected surface is about 91%, contrast of projection fringe is better than 0.8, and keep the fringe pitch uniform. Optical projector designed in this paper provides guarantee for inspection application and following fringe analysis.