针对同一光学产品的杂光系数由于测试条件的不同，测试结果往往差别很大，无法进行准确比较的问题，对几种光学镜头在不同的测试条件下反复进行了杂光系数测试实验。通过理论分析和实验测试给出了不同黑体目标尺寸和接收光阑孔径以及是否加装准直镜对杂光系数测量结果的影响。结果表明，对同一光学产品，选取的黑体目标尺寸越大，测试结果杂光越小；选取的光电接收器件接收光阑孔径越大，测试结果杂光越大。另外，准直物镜的使用会引入新的杂光，令杂光测试结果增大，但增大的量值可视为定值，进而从测试结果中减除。

The same optical product can show different stray light coefficients in different measuring conditions, and it is impossible to compare the different results correctly. According to this situation, the stray light coefficients of several kinds of optical lenses have been experimentally investigated in different measuring conditions, such as sizes of block body, receiving apertures of photoelectric device and mounting the collimating objective or not, and the theoretical analysis and experimental results supply the dependences of stray light coefficients on test conditions. The experimental results indicate that the larger size of the black body, the smaller value of stray light; the larger receiving aperture of photoelectric receiving device, the larger value of stray light; the use of collimating objective will induce new stray lights which increase the value of stray light in experiments, but the increased part can be deducted from the results, as the value can be seen a fixed one.