[OPTICAL REVIEW Vol. 1, No. 1 (1994) 94-96]
On Optical Sensing of Alkali Halide Crystal Surfaces
P. KETOLAINEN, R. SILVENNOINEN, K.-E. PEIPONEN and P. RAERINNE
Väisälä Laboratory, Department of Physics, University of Joensuu, P.O. Box 111, FIN-80101 Joensuu, Finiand
(Accepted August 4, 1994)
The surface quality of alkali halide crystals to be used in spectroscopy and as laser components has been sensed using a computer-generated hologram together with digital image processing. FFT and two-dimensional cross-correlation analyses. Surfaces cleaved only or finished to various extents are considered as examples.
Key words : optical sensing, surface quality, surface roughness, computer-generated hologram, image processing, fast Fourier transform, cross-correlation analysis