猫眼波前定位虚实结合干涉非球面参数误差测量(特邀)

Virtual-real combination interferometry for aspheric surface parameter error measurement with cat-eye-wavefront positioning (invited)

非球面广泛应用于光学系统中。表征非球面的基本参数包括顶点曲率半径、圆锥系数以及高阶非球面系数,它们贯穿了非球面的设计、制造、检测、装调过程。对非球面参数的高精度测量是加工和装调的前提。提出了一种基于虚实结合干涉仪的部分补偿非球面参数误差测量系统。在该系统中,采用部分补偿干涉法测量剩余波前,复用干涉仪利用轴向扫描透镜的猫眼波前定位法测量补偿镜与被测镜之间的间距,采用虚实结合迭代算法进行参数误差求解。该系统仅需在部分补偿干涉光路中引入会聚透镜,装调简单,测量精度高。通过一个四次非球面参数误差测量实验验证了该方法的有效性和精度。

Aspheric surfaces are widely used in optical systems. Aspheric surface parameters, including vertex radius of curvature, conic constant, and high-order aspheric coefficients participate in optical design, manufacture,measurement, alignment and assembly. Precision measurement for aspheric surface parameters is the basis for manufacture, alignment and assembly. A partial compensation measurement system is proposed based on virtualreal combination interferometer for aspheric surface parameter error measurement. In this measurement system,residual wavefronts are measured by partial compensation interferometry. The interferometer is multiplexed in cat-eye-wavefront positioning method to measure the compensation distance which is the distance between compensator and aspheric surface under test. Aspheric surface parameter errors are calculated by virtual-real combination iterative algorithm. The system only needs to introduce a converging lens into the optical path of partial compensation interferometry, which is easy to align and assemble, and has high measurement accuracy.The effectiveness and accuracy are verified through the measurement of a 4th-order aspheric surface.