The use of multiple-beam interferometry makes it possible to observe very small deviations in the flatness of optical surfaces. A method is described which reduces the contour interval between multiple beam fringes to between 1/20 and 1/100 wavelength. This method has been applied to the critical examination of a quantity of Fabry-Perot plates for use in continuous helium-neon optical masers.
No takes yet. Share an insight, caveat, or question.
D. R. Herriott (1961) studied this question.
Synapse has enriched one closely related paper. Consider it for comparative context: