In order to improve the low transmittance of the oblique incident lig ht in the conventional diffuser plate,while in the design of LED lamps and lanterns witho ut light guide plate,based on geometrical optics and Fresnel formulas,the surface microstruct ures of diffuser plate with high-performance anti-reflection properties for oblique incident li ght are designed. Parameter formulas of three prismatic microstructures for high efficiency light transmission are derived theoretically.Diffuser modeling using Solidworks software,the inf luence of micro-structural parameters of diffusers on light transmission efficiency and i lluminance uniformity on the lighting surface are analyzed by ray tracing simulation using TracePro software. The results show that not only the size and shape of non-isosceles prism on the surface of light incident side can but also the concave spherical microlens diameter on the surfa ce of light exit side can influence the obliquely incident light transmissi on efficiency greatly.At 1mm distance from the diffuser surface of light exit side,optimization of parameters makes the li ght transmission efficiency be 0.92and the illumination uniformity be 96.8%,and the illuminatio n uniformities at different distances from the diffuser surface of light exit side can all reach m ore than 80%. The diffuser plate according to the optimal parameters obtained by theoretic al analysis is fabricated and the transmission efficiency of 0.91is achieved.