摘要 |
A computer assisted optical instrument analyzes a differential wave front developed by subtracting the wave front due to a circular grating reticle only in the optical path, from the wave front due to a reflecting surface being analyzed in the optical path including the reticle, to obtain a Foucault shadow fringe pattern indicating the surface curvature. The differential wave front is analyzed by the circular grating and a CCD camera, in polar coordinates, to obtain polynomial coefficients defining the wave front. The polynomial is then plotted and displayed as the topographic shadow fringe pattern of the reflected surface. Dedicated lens and reflector combinations adapt the instrument to specific embodiments in ophthalmology and metrology.
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