05768443 is referenced by 77 patents and cites 6 patents.

A method is provided for use in a multi-camera machine vision system wherein each of a plurality of cameras simultaneously acquires an image of a different portion of an object of interest. The invention makes it possible to precisely coordinate the fields of view of the plurality of cameras so that accurate measurements can be precisely performed across multiple fields of view, even in the presence of image distortion within each field of view. The method includes the steps of, at calibration-time, fixing the plurality of cameras with respect to a substantially rigid dimensionally-stable substrate including a plurality of calibration targets each having a reference feature. For each camera, an image of a calibration target is acquired to provide a plurality of acquired calibration target images. Then a distortion-correction map is generated for each acquired calibration target image. At run-time, for each camera, an image is acquired, at least two of the images including a portion of the object to provide a plurality of partial object images. These partial object images are then transformed by a distortion-correction map to provide a plurality of corrected partial object images. Next, relative displacement information is used to determine the relative displacement of a first point in a first corrected partial object image with respect to a second point in a second corrected partial object image. A combined map can be generated that both corrects image distortion, and transforms local camera coordinates into global coordinates.

Title
Method for coordinating multiple fields of view in multi-camera
Application Number
8/574733
Publication Number
5768443
Application Date
December 19, 1995
Publication Date
June 16, 1998
Inventor
Aaron Wallack
Natick
MA, US
David Michael
Newton
MA, US
Agent
Russ Weinzimmer
Assignee
Cognex Corporation
MA, US
IPC
G06K 9/32
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