05142648 is referenced by 17 patents and cites 21 patents.

Video monitors sequentially displaying coarse bar patterns of various spatial frequencies are spaced two feet or more from a painted surface to be inspected. Video cameras, also spaced far from the surface, view the images reflected from the paint and a computer system analyzes the images by determining the modulation transfer function (MTF) of each reflecting surface. Surface curvature is compensated for by selecting the spatial frequencies in the sequence of patterns in accordance with the effect of the curvature on a reference pattern. The area under the MTF curve correlates to the distinctness of image of the surface and the area under the low spatial frequency portion of the curve correlates to orange peel.

Title
Method and apparatus for paint inspection
Application Number
7/562059
Publication Number
5142648
Application Date
August 2, 1990
Publication Date
August 25, 1992
Inventor
Nilesh C Thakker
West Hills
CA, US
Douglas M Linn
Walled Lake
MI, US
John M Fitts
Santa Monica
CA, US
Agent
Charles E Leahy
Assignee
General Motors Corporation
MI, US
IPC
G01N 21/55
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