Measurement accuracy verification of aspheric surface test with computer-generated hologram

• 来源期刊: 中国光学快报（英文版）
• 年，卷（期）: 2012,（7）
• 页码范围: 35-38
• 页数: 4页
• 语种: 英文
• DOI: 10.3788/COL201210.071201

摘要

A convex aspheric surface using a computer-generated hologram (CGH) test plate fabricated with novel techniques and equipment is tested.However,the measurement result is not verified via comparison with other methods.To verify the accuracy of the measurement,a perfect sphere surface is measured by the following.The measurement result is quantified into four parts:the figure error from the tested spherical surface; the figure error from the reference spherical surface; the error from the hologram; and the adjustment error from misalignment.The measurement result,removed from the later three errors,shows agreement to 4-nm RMS with the test by Zygo interfermeter of the same surface.Analysis of thc CGH test showed the ovcrall accuracy of the 4-nm RMS,with 3.9 nm from the test plate figure,0.5 nm from the hologram,and 0.74 nm from other sources,such as random vibration,various second order effects,and so on.Thus,the measurement accuracy using the proposed CGH could be very high.CGH can therefore be used to measure aspheric surfaces accurately.