提出了低偏振分离的立方棱镜带通滤光片的设计方法。为减小光在立方棱镜中s、p偏振光的偏振分离, 采用三种材料来构成带通滤光片的反射镜, 并采用不同折射率排列的反射镜结构构成嵌入式的多个带通滤光片, 既提高了s、p偏振光的通带透射率, 又减小了s、p偏振光在通带中的偏振分离和偏振位相差。通过改变反射镜的基本周期数和滤光片的周期数, 可以调节滤光片的通带宽度和截止度, 经膜厚优化, 得到满意的设计结果。

The paper puts forward the design method of cubic-prism bandpass filter with low polarization separation. To reduce s-and p-polarization separation in the cubic prism, three kinds of materials are used to form reflectors of the bandpass filter and the refractive index arrangement of reflector structures embedded multiple band pass filters is analyzed. It can not only improve the transmittance of the passband filter, but also decrease the polarization separation and polarization phase difference of the s- and p-polarized light. By changing the mirror basic period and filter period, it can adjust the passband bandwidth and the extinction ratio of the filters. By optimizing the thickness of the layers, the desired design results can be obtained.