Absolute measurement method for correction of low-spatial frequency surface figures of aspherics

作者：Lin Wei Cheng^*; Chang Shenq Tsong; Ho Cheng Fang; Kuo Ching Hsiang; Chung Chien Kai; Hsu Wei Yao; Tseng Shih Feng; Sung Cheng Kuo

来源：Optical Engineering, 2017, 56(5): 055101.

DOI：10.1117/1.OE.56.5.055101

• computer-generated holograms
• Zernike coefficient
• absolute aspheric testing
• random ball test
• gravity distortion
• mounting deformation

An absolute measurement method involving a computer-generated hologram to facilitate the identification of manufacturing form errors and mounting-and gravity-induced deformations of a 300-mm aspheric mirror is proposed. In this method, the frequency and magnitude of the curve graph plotted from each Zernike coefficient obtained by rotating the mirror with various orientations about optical axis were adopted to distinguish the nonrotationally symmetric aberration. In addition, the random ball test was used to calibrate the rotationally symmetric aberration (spherical aberration). The measured absolute surface figure revealed that a highly accurate aspheric surface with a peak-to-valley value of 1/8 wave at 632.8 nm was realized after the surface figure was corrected using the reconstructed error map.

• 出版日期2017-5
• 单位清华大学