04448527 is referenced by 14 patents and cites 2 patents.

The detection of surface defects in mechanical parts is effected by the analysis of diffracted light coming from these defects. The detection method includes the steps of illuminating the surface of the part to be examined with incoherent light and forming a flat image of the said surface in a transparent photosensitive layer of a spatial light modulator. The spatial distribution of the intensity of the incoherent light reflected by the said surface produces a corresponding and proportional spatial distribution of values of refractive index in the photosensitive layer. This layer is illuminated with plane polarized, coherent light by frame scanning in elementary areas. During the scanning operation, the variations in at least one of the polarization components of the coherent light are detected by a matrix of converters after the light has traversed the said transparent photosensitive medium.

Method and apparatus for detecting surface defects in mechanical workpieces
Application Number
Publication Number
Application Date
February 8, 1982
Publication Date
May 15, 1984
Emilio Milana
Sughrue Mion Zinn Macpeak and Seas
Centro Ricerche Fiat S p A
G01N 21/00
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