Abstract
A two-dimensional surface profile imaging technique that uses a low-coherence heterodyne interferometer is proposed. A double-grating frequency shifter was used in a tandem interferometer to provide the achromatic frequency shift for low-coherence light. A chopper, together with a processing circuit, was implemented to modulate the interference fringes. The surface profile was measured from the interference fringes taken by a CCD camera using a five-step method. The uncertainty in the displacement measurement is 0.34 μm for a displacement range of 43 μm. The surface profile of a glass sample with low effective reflectivity was acquired.
© 2005 Optical Society of America
Full Article | PDF ArticleMore Like This
Sheng-Hua Lu, Hsiao-Ping Chiang, Che-Yu Lin, and Che-Chung Chou
Appl. Opt. 53(6) 1047-1051 (2014)
Youichi Bitou
Appl. Opt. 44(9) 1577-1581 (2005)
Madhuri Thakur, Cho Jui Tay, and Chenggen Quan
Appl. Opt. 44(13) 2541-2545 (2005)