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Some technical applications of reflected‐light interference microscopy
Author(s) -
ARREGGER CONSTANCE E.
Publication year - 1967
Publication title -
journal of the royal microscopical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.569
H-Index - 111
eISSN - 1365-2818
pISSN - 0368-3974
DOI - 10.1111/j.1365-2818.1967.tb04505.x
Subject(s) - interference microscopy , optics , magnification , monochromatic color , flatness (cosmology) , interference (communication) , materials science , microscopy , chromatic aberration , microscope , chromatic scale , physics , computer science , computer network , channel (broadcasting) , cosmology , quantum mechanics
SYNOPSIS The use of interference techniques in microscopy provides a useful tool for scientists and engineers in the investigation and measurement of very small changes in height on a reflecting surface. The interference fringes may be regarded as contour lines spaced at half the wave length of the monochromatic light used for illumination. This gives, in effect, a remarkably high magnification in depth and makes possible the assessment of the variations of flatness and finish of highly finished surfaces and the measurement of the thickness of vacuum evaporated films and the height of surface steps on crystals. Replica techniques can be used for the examination of inaccessible surfaces and also for the variation of the value of the fringe spacing if the pellicle is viewed when immersed in liquids of various refractive indices, thus varying the effective magnification and hence the range of measurement. Further, the use of fringes of equal chromatic order, involving the use of a spectroscope as an accessory to the microscope, as described by Tolansky and others, enables depth measurements to an accuracy of a few micrometres to be made readily.