Abstract: A feature detection apparatus includes a reflective imaging system, a transmissive imaging system, and memory for generating an image of a workpiece. The reflective imaging system generates a first bit image of a surface of the workpiece. The transmissive imaging system generates a second, different bit image of the density of the workpiece. The two images are then combined in memory into a more complete image that contains data describing the surface and interior of the workpiece. The apparatus also includes a filter for enhancing the combined bit image so that physical features of the workpiece are accurately detected. The filter is constructed to perform the following steps. For detecting a feature of interest, the filter determines a mean, standard deviation, and normal distribution of the image's pixel intensities.
Type:
Grant
Filed:
January 30, 1997
Date of Patent:
April 6, 1999
Assignee:
Techne Systems, Inc.
Inventors:
John R. Goulding, Cary S. Kiest, Joseph G. LaChapelle