传统自由曲面LED配光透镜由于在自由曲面求解时存在误差,往往导致最终配光效果不理想。为了进一步提高配光效果,提出基于非球面内表面调制的自由曲面配光透镜设计方法,采用非球面内表面对自由曲面的求解误差进行补偿,有效地减小了自由曲面的误差对配光效果的影响。通过对自由曲面求解误差进行定量计算,建立用于补偿误差的非球面内表面设计方法,形成了基于非球面内表面调制的自由曲面配光透镜的完整的设计思路。将这一方法应用于矩形照明区域的LED路灯透镜设计之中,相对于传统自由曲面配光透镜,照度均匀度由0.66提高到0.73,能量利用率从47.3%提高到63.2%。
In the free-form surface construction process, the solution deviation is produced, which will lead to the poor illumination performance of the traditional free-form lens. To make the illumination performance better and increase energy efficiency, a free-form lens design method based on the modulation of the aspheric inner surface was proposed. The aspheric inner surface was used to modify the deviation of the free-form surface. With a proper aspheric inner surface, the expected illumination performance was obtained and the energy efficiency was increased. By calculating the deviation of the free-form surface, the relationship between the incident ray and the slope of the inner surface was built. Taking an LED street light as an example, by using the method, the uniformity of illumination improved from 0.66 to 0.73, and the light usage efficiency is improved from 47.3% to 63.2%.