Weihong SONG^1,2*, Fan WU¹, Xi HOU¹, Wenchuan ZHAO¹, and Yongjian WAN¹

¹Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209, China
²University of Chinese Academy of Sciences, Beijing 100039, China

(Received June 4, 2013; Accepted July 8, 2013)

We present an absolute measurement of flats in a Fizeau interferometer with the method of shift-rotation, which only requires rotational measurements and shift measurement with a translation. Experiments have been carried out to verify the validity of the absolute testing method, and the results show that the reference surface deviation measured with the shift-rotation method agrees well with that of another calibration result with traditional three-flat absolute procedure; the root-mean-square (RMS) of the residual figure between them is ∼0.4 nm.

Key words: absolute measurement, shift-rotation, interferometry, surface measurements

^*E-mail address: songscu@163.com