Abstract

Measurement of aspheric and freeform surfaces remains challenging due to the various shapes of the surface under test (SUT), especially when the SUT has a large aperture and strong deviation from the spherical surface. This paper proposes a two-step carrier-wave stitching method to enlarge the measurement bandwidth of a digital Moiré interferometry. Then, measurements of aspheric and freeform surfaces with a standard spherical interferometer without a phase-shifting mechanism are demonstrated. Experimental results with a root-mean-square repeatability of better than $1/200\lambda$ present good consistency to UA3P contact measurement results. Further simulation results with different residual wavefronts confirm measurement accuracies of peak-to-valley value of ${10}^{-3}\lambda$. The method is effective for large residual wavefronts and thus has potential for flexible measurement of aspheric and freeform surfaces.

© 2018 Optical Society of America

Virtual interferometer calibration method of a non-null interferometer for freeform surface measurements

Qun Hao, Shaopu Wang, Yao Hu, Hanglin Cheng, Meng Chen, and Tengfei Li
Appl. Opt. 55(35) 9992-10001 (2016)

Measurement investigation of an off-axis aspheric surface via a hybrid compensation method

Shijie Li, Jin Zhang, Weiguo Liu, Zhongda Guo, Hong Li, Zhiqiang Yang, Bingcai Liu, Ailing Tian, and Xiaoqin Li
Appl. Opt. 57(28) 8220-8227 (2018)

Vertex radius of curvature error measurement of aspheric surface based on slope asphericity in partial compensation interferometry

Qun Hao, Tengfei Li, Yao Hu, Shaopu Wang, Yan Ning, Yifeng Tan, and Xinmu Zhang
Opt. Express 25(15) 18107-18121 (2017)

Non-null annular subaperture stitching interferometry for steep aspheric measurement

Lei Zhang, Chao Tian, Dong Liu, Tu Shi, Yongying Yang, Hanshuo Wu, and Yibing Shen
Appl. Opt. 53(25) 5755-5762 (2014)

Modified stitching algorithm for annular subaperture stitching interferometry for aspheric surfaces

Yongfu Wen, Haobo Cheng, Hon-Yuen Tam, and Dongmei Zhou
Appl. Opt. 52(23) 5686-5694 (2013)