针对直下式发光二极管(LED)平板光源,在矩形阵列排布条件下,通过照度图的对称性分析,采用一种基于分段式配光曲线生成折射率为1.4935的配光透镜的方法,从而实现整体照度均匀。设置距高比为4.1,以方形阵列排布的直下式LED平板光源为例,通过能量分配设计方法完成配光透镜的设计,仿真结果表明,目标面上照度的均匀度高于0.85,光效达到0.9以上,并适用于扩展光源。利用对称性分析可得到上述直下式LED平板光源出光面所能达到的均匀度上限,这对LED平板光源的光学设计具有指导意义。 According to the symmetry analysis of the illuminance map under the condition of rectangular array, aiming at the direct light-emitting diode (LED) flat panel light source, a method of generating a light distributing lens with a refractive index of 1.4935 based on the sectional light distribution curve is adopted To achieve the overall illumination uniformity. As an example, a straight-type LED flat panel light source with a height-to-height ratio of 4.1 and arranged in a square array was used as an example to design a light distributing lens through an energy distribution design method. The simulation results show that the illuminance uniformity on the target surface is higher than 0.85. Reaches 0.9 above, and is suitable for expanding the light source. Using the symmetry analysis, the upper limit of the uniformity that can be achieved by the light emitting surface of the direct type LED flat panel light source can be obtained, which has guiding significance for the optical design of the LED flat light source.