为了提高点源透过率(PST)测试系统的杂散光测试能力及测试精度, 提出并设计了一种标准镜头, 用于在大离轴角范围内对系统的杂散光测试范围及测试精度进行标定。利用简单的物理模型设计了一种在实验室内对点源透过率测试系统杂散光测试精度定标的标准镜头; 测量了标准镜头的表面物理参数, 并将其带入TracePro软件计算出了不同离轴角对应的PST。对设计分析的PST值与实测的PST值进行比较, 从而计算得到了该测试系统的测量精度。验证实验表明, 该标准镜头的PST分析值与实测值之差优于lg/0.5, 满足实验室内对点源透过率测试系统杂散光测量精度进行标定的要求, 是PST绝对测量的可靠方法。该项技术为国内PST测试系统的精度校准问题提供了技术保障。

To improve the stray light testing ability and calibration accuracy of the stray light equipment used in test of the Point Source Transmittance (PST), a calibration lens was proposed to calibrate the testing range and testing accuracy of the equipment in a large off-axial angle. By using a simple physical model, the calibration lens was designed in a laboratory. The physical parameters of the calibration lens were measured, then these parameters were taken into the TracePro to calculate the PSTs in different off-axial angles. Finally, the calculated result and the tested result of PSTs were compared, and the test accuracy of the equipment were obtained. The experimental results indicate that the difference between calculate results and testing results of the calibration lens is better than lg/0.5, meeting the need of testing accuracy calibration of the stray light equipment in testing PSTs and providing a reliable reference for the absolute measurement of PSTs. This technology solves the problem in testing accuracy calibration of PST measuring systems.