双面镀膜法制备高面形精度滤光片

Research on high surface shape accuracy filter fabricated by dual-deposition method

对双面镀膜法制备高面形精度滤光器件进行研究,通过在一面沉积带通滤光膜,另外一面沉积应力/形变匹配膜层的方式,制备了外径Φ25 mm,径厚比为10∶1的HWB900基底高面形精度带通滤光膜。测试结果显示:在通带1 215 nm~1 265 nm波段的平均透过率■≥92%,截止带900 nm~1 135 nm、1 345 nm~1 700 nm内透过率■<1%,镀膜后零件2个表面的均方根(root-mean-square,RMS)值均优于λ/20。深入分析双面镀膜时2个表面面形的变化规律,确定了匹配膜层的厚度及该方法的使用特点。该方法实践性强,制备的光学器件光学性能优异,面形精度高,对高面形精度光学器件的制备具有重要参考价值和指导意义。

The preparation of high surface shape accuracy bandpass filter by double-sided coating method was studied,and the HWB900 substrate high surface shape accuracy bandpass filter film with outer diameter ofΦ25 mm and diameter-thickness ratio of 10:1 was prepared by dual-deposition.On one side the bandpass filter film was deposited and the matching layer was then coated to eliminate the stress-induced deformation on the ■ other side.The results show that the mean transmittance is greater than or equal to 92%in the passband■between 1215 nm~1265 nm,the transmittance max is less than 1%in the rejection band between 900 nm~1135 nm and 1345 nm~1700 nm,and the root-mean-square(RMS)values of both side are superior thanλ/20.Following a comprehensive analysis of the deformation law in both side,the thickness of the matching layer and the use characteristics of this method were determined.The described method has high practicality,and the prepared optical devices have excellent optical performance and high surface accuracy,which has important reference value and guiding significance for the preparation of optical devices with high surface shape accuracy.