倾斜分束片型复色自准直仪光学系统

Optical system of tilted beam splitter type multicolor autocollimator

为了实现对倾斜分束片型自准直仪的设计,针对由平板分束器引入的轴上像散提出了校正方法。对其轴上点像散产生的原因进行分析,研究了柱面镜对轴上像散的校正方法。推导了柱面镜校正参数的计算方法,针对复色自准直仪系统的残余色差,提出柱面分束器与柱面镜组合的校正方法,并与平板分束器与双柱面镜组合方法进行对比,分析发现前者可减少元件数量,更适合用于倾斜分束片型复色自准直仪中。设计结果表明,柱面分束器与柱面镜组合型系统的波像差RMS值为λ/26,PV值为λ/5,系统的消像散、消色差效果良好,成像质量得到有效复原。对样机的波前进行检测,RMS值为λ/25,PV值为5λ/26,小于λ/4,系统成像质量良好。

To design a tilted beam splitter type autocollimator,a method of correcting the on-axis astigmatism introduced by the plate beam splitter is proposed herein. The reason behind the astigmatism of the points on the axis is analyzed,and the method of correcting this astigmatism using a cylindrical lens is studied. A method of calculating the correction parameters for the cylindrical lens is developed. To tackle the residual chromatic aberration problem of the polychromatic autocollimator system,the correction method of combining the cylindrical beam splitter and cylindrical lens is proposed and compared with the method of combining the plate beam splitter and double cylindrical lens. The former is found to be better through a comparative analysis. The number of components can be reduced,and is more suitable for use in a tilted beam splitter type multicolor autocollimator. The design results indicate that the RMS value of the wave aberration of the system combining the cylindrical beam splitter and cylindrical lens is 1/26 waves,and the PV value is 1/5 waves. The system shows good astigmatism and achromatic effects. The image quality is effectively restored. Detecting the wavefront of the prototype,the RMS value is 1/25 waves,and the PV value is 5/26 waves,which is less than a quarter of the wave. The system imaging is good,verifying the correctness and feasibility of the design.