Method and apparatus for detecting characteristic features of surfaces
First Claim
1. A system for identifying a face on a three dimensional test body on a stage by comparing an optical representation of the face with stored signals indicative of optical representations of comparison faces of three dimensional comparison bodies, said system comprising:
- means for illuminating said comparison faces sequentially and for generating and storing an optical representation of the relative amounts of white, gray and black areas on each comparison face.means for illuminating said test body in a first direction and for creating an optical image,means for receiving the optical image in a second direction oblique to said first direction,means for generating electrical signals representative of the relative amount of white, gray and black area as viewed in said second direction,means for generating a signature signal comprising information representative of said relative amounts of white, gray and black areas on the face of the test body, andmeans for comparing the signature signal of the face with the stored signals indicative of optical representations of the comparison faces to determine which face is being viewed.
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Accused Products
Abstract
A novel system is provided for detecting the presence of a characteristic feature on an illuminated surface of an object when used in conjunction with known electro-optical systems for determining the position of the centroid of the outline of the object with relation to the supporting surface and the rotation of the object relative to the rotational orientation of a test part. The surface is illuminated at an angle that enhances the contrast of the characteristic feature while using a vidicon-type image converter tube which scans the field which includes the object. The location, with respect to the centroid, of a circular window area encompassing the characteristic feature and the radius of the circular window are determined utilizing a television monitor connected to the vidicon. Next the operator determines and stores a pair of separated threshold levels which control a level detector which compares the vidicon output to the threshold level to derive a binary output so that one of the threshold levels separates the white area in the window area from the gray-black area while the other threshold level separates the black area in the window area from the white-grey areas. The system then analyzes and stores the relative amounts of white, gray and black areas in the window as a signature signal representative of the characteristic feature of the surface. Following this "teach" phase, the system may be used to determine whether a subsequent object contains a feature which correlates well with the characteristic of the test part by analyzing the output of the vidicon at the window for both threshold levels and determining the correlation between these levels and the values obtained during the teach phase.
25 Citations
9 Claims
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1. A system for identifying a face on a three dimensional test body on a stage by comparing an optical representation of the face with stored signals indicative of optical representations of comparison faces of three dimensional comparison bodies, said system comprising:
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means for illuminating said comparison faces sequentially and for generating and storing an optical representation of the relative amounts of white, gray and black areas on each comparison face. means for illuminating said test body in a first direction and for creating an optical image, means for receiving the optical image in a second direction oblique to said first direction, means for generating electrical signals representative of the relative amount of white, gray and black area as viewed in said second direction, means for generating a signature signal comprising information representative of said relative amounts of white, gray and black areas on the face of the test body, and means for comparing the signature signal of the face with the stored signals indicative of optical representations of the comparison faces to determine which face is being viewed. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
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9. A method of identifying a face of a test object relative to faces of comparison objects, the steps of the method comprising:
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identifying individually a plurality of faces of comparison objects by illuminating a face in at least two directions to create a comparison image;
producing a comparison signal representative of the relative amount of white and black at two different gray-level thresholds for each face; and
storing the comparison signal as representative of the face;illuminating the test object in at least two directions to create a test image of the test object; generating a signature signal indicative of the relative amounts of white and black in the test image at corresponding to two different gray-level thresholds; and comparing the signature signal generated with at least one of the stored comparison signals to identify the test object with respect to the faces of the comparison objects, whereby the face of the test object may be identified as corresponding to one of the faces of the comparison objects.
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Specification