Share Email Print
cover

Optical Engineering

Diffraction-grating interferometer for testing aspheric concave mirrors with optimization of fringe visibility
Format Member Price Non-Member Price
PDF $20.00 $25.00

Paper Abstract

We describe a diffraction-grating interferometer that enables us to obtain a high contrast ratio of 120 between the test wave and the reference wave by optimizing the groove shape of a blazed-type diffraction grating. The high contrast provides good visibility for the resulting interference fringes when testing aspheric mirrors using computer-generated holograms (CGHs). Generally CGHs perform wavefront nulling, but greatly attenuate the intensity of the test wave. We present experimental results for an aspheric concave mirror of 600 mm diameter obtained using a blazed diffraction grating with a 1/1200 mm groove spacing and a 17-deg blazed angle. The binary-type CGH used for the experiments provided low transmittance efficiency but was cost effective.

Paper Details

Date Published: 1 September 2004
PDF: 5 pages
Opt. Eng. 43(9) doi: 10.1117/1.1778177
Published in: Optical Engineering Volume 43, Issue 9
Show Author Affiliations
Tae-Joon Hwang, Korea Advanced Institute of Science and Technology (South Korea)
Seung-Woo Kim, Korea Advanced Institute of Science and Technology (South Korea)


© SPIE. Terms of Use
Back to Top