A general graphical convolution method for fringe analysis of testing methods that use a spatially incoherent light source is presented. Results are shown for the grating-slit test using optical narrow and cross slits. The convolution method shows that phase shifting grating-slit test can be done with the cross slit at the expense of a reduced fringe contrast ratio. A phase shifting measurement with a cross-slit modulator yields high measurement precision and validates our fringe contrast theory.
© 2010 Optical Society of America
Optical Design and Fabrication
Original Manuscript: October 7, 2009
Revised Manuscript: December 11, 2009
Manuscript Accepted: December 16, 2009
Published: February 8, 2010
Chao-Wen Liang, Chien-Fu Ou, and Jose Sasian, "Phase shifting grating-slit test with a cross slit," Opt. Lett. 35, 496-498 (2010)