应用SiC反射镜表面改性技术提高TMC光学系统信噪比  

Improvement of signal noise ratio of TMC optical system by SiC surface modification technology

作　　者：陈红[1] 王彤彤[1] 高劲松[1] 巩盾[1,2] 王笑夷[1] 郑宣鸣[1] 申振峰[1,2] 张忠玉[1] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所中国科学院光学系统先进制造技术重点实验室,吉林长春130033 [2]中国科学院研究生院,北京100049

出　　处：《光学精密工程》2009年第12期2952-2958,共7页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.60478035)

摘　　要：为了消除SiC反射镜的固有缺陷,提高反射式光学系统的信噪比,使用SiC表面改性技术对同轴三反射(TMC)光学系统的SiC反射镜进行了处理。首先,应用等离子体辅助沉积(PIAD)技术沉积了一层Si改性层,接着对改性层进行精密抛光,然后在反射镜表面镀制Ag膜和增强膜,最后获得了表面改性对TMC光学系统信噪比的影响。Wyko轮廓仪测试表明,SiC反射镜的粗糙度Ra由10.42nm降低到了0.95nm;镀制高反射膜后,主镜、次镜、三镜及折叠镜在0.5～0.8μm可见光波段的反射率>98%。计算结果表明,应用了表面改性技术后TMC反射式光学系统的信噪比提高了5%以上,说明SiC表面改性技术是一种提高TMC光学系统信噪比的有效方法。A SiC surface modification technique was applied to a TMC （Three Mirror Coaxis） reflective optical system to eliminate the intrinsic defects of SiC mirrors and to improve the Signal Noise Ratio （SNR） of the reflective optical system. Firstly, a Si layer as a modified coating was deposited on the SiC mirror surface. Then, a fine polish process was employed in the modified layer and the high reflective coatings composed of a silver film and enhancing films were deposited on the mirror surface. Fi nally, the effect of surface modification on the TMC reflective optical system was obtained. The meas urement by a Wyko profilometer indicates that the roughness Rn of the SiC mirror is reduced from 10.42 nm to 0.95 nm and the reflectivities of the primary mirror, secondary mirror, tertiary mirror and fold mirror are all higher than 98% between 0. 540.8 μm. Calculation results indicate that the SNR has impr.oved more than 5% after surface modification, which proves that surface modification technique is an effective way to improve the SNR of a TMC reflective optical system.

关 键 词：TMC系统 表面改性 SiC反射镜 信噪比 

分 类 号：O484.4[理学—固体物理] TH703[理学—物理]