CdSe波片6~12μm波段增透膜研究

Study on 6-12μm Anti-reflection Coating for CdSe Wave Plate

采用垂直无籽晶气相升华法生长出直径37 mm的优质硒化镉(CdSe)单晶体,并沿光轴方向切割出20 mm×20 mm×3 mm的CdSe波片初胚。经研磨和抛光,在2~20μm波段CdSe波片的红外透过率约为70%。为进一步提高波片的透过率,采用Essential-Macleod软件辅助设计方案,选用YF3和ZnS为双层增透膜材料,并获得最佳的膜系厚度。镀膜后的CdSe波片在6~12μm波段透过率达到90%,在10.5μm处的透过率最高,峰值高达99%。

High quality CdSe single crystal with diameter of 37 mm was grown by the modified vertical unseeded sublimation method,and the embryo of CdSe wave plate with size of 20 mm×20 mm×3 mm was cut along the optical axis.After grinding and polishing,the infrared transmittance test results show that the transmittance of the CdSe wave plate in the range of 6-12μm was about 70%.In order to further increase the transmittance of the CdSe wave plate,the Essential-Macleod software-assisted design solution was adopted.YF3 and ZnS were selected as the two-layer anti-reflection coating materials,and the optimal film thickness was obtained.The coated CdSe wave plate had a transmittance of 90%in the 6-12μm band,and the highest transmittance at 10.5μm,with a peak of 99%.