skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Slope measurement of bent plates using double grating shearing interferometry

Journal Article · · Applied Optics
DOI:https://doi.org/10.1364/AO.50.002958· OSTI ID:22036631

A grating-based shearing interferometeric setup for slope measurement of bent plates has been proposed. The specimen under test is illuminated by a collimated beam from the laser. Light reflected from the specimen passes through two identical holographic gratings placed in tandem. The grating frequency has been so chosen that the diffracted orders from each grating are separated out distinctly. Two first-order beams diffracted from each of the gratings superpose in space. In the resulting interferogram, the fringes due to slope information of the object are visualized. Mathematical formulation for experimental determination of slope values has been undertaken. Validation of the experimental results with theoretical predictions in case of cantilever beam provides good correlation. The main advantage of the technique has been the realization of very compact geometry without the need for spatial filtering arrangement commonly associated with the grating-based techniques used to date.

OSTI ID:
22036631
Journal Information:
Applied Optics, Vol. 50, Issue 18; Other Information: (c) 2011 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6935
Country of Publication:
United States
Language:
English