A new scanning common-path interferometric profiler capable of absolute-phase measurement is described. The key element is a computer-generated hologram, which acts as the beam-splitting element. Unlike most absolute phase systems, it can be made entirely common path with respect to piston microphonics and is thus exceptionally stable. In addition to operating in scanning mode, the optical configuration permits simultaneous operation as a single-shot phase measuring interferometer and is thus capable of simultaneous form and texture measurements. The operation and stability of the scanning profiler are demonstrated experimentally.
© 1998 Optical Society of America
(090.1970) Holography : Diffractive optics
Original Manuscript: June 15, 1998
Revised Manuscript: June 15, 1998
Published: October 1, 1998
Nicolas B. E. Sawyer, Chung Wah See, Matthew Clark, Michael G. Somekh, and Jason Y. L. Goh, "Ultrastable absolute-phase common-path optical profiler based on computer-generated holography," Appl. Opt. 37, 6716-6720 (1998)