Patent ID: 6728417
Filing Date: 2004-04-27
Classification: G01B

Abstract:
A measurement apparatus operating with camera means, an image processing device, and calibration means for performing calibration of the camera means and generating calibration information, in which the presence of a measurement object is detected on the basis of a reference image of a reference object obtained by the camera means taught in advance, and on the basis of an image of a measurement object obtained by the camera means, and based on measurement of one or more geometric characteristic elements of the measurement object, wherein the reference object and the measurement object have substantially the same form, the image processing device comprising:corrected reference image forming means for forming a corrected reference image by using the calibration information to correct said reference image so that a lens distortion or a distortion caused by performing image pickup in a diagonal direction is reduced; and corrected measurement object image forming means for forming a corrected image of the measurement object by using the calibration information to correct said image of the measurement object so that a lens distortion or a distortion caused by performing image pickup in a diagonal direction is reduced, and where detection of the presence of the measurement object is based on the measurement of the one or more geometric characteristics of the measurement object in the corrected image of the measurement object and on the basis of the corrected reference image.