METHOD FOR EXECUTING THREE=DIMENSIONAL MEASUREMENT UTILIZING CORRECTIVELY COMPUTING THE ABSOLUTE POSITIONS OF CCD CAMERAS WHEN IMAGE DATA VARY

A method of measuring three-dimensional dimension of a object comprising the steps of installing two or more than two of CCD cameras, installing a plurality of reference-point members to at least four locations in the periphery of or on a measurable object, installing a reference bar having a known distance between a pair of points thereof, computing positions of respective measurable points based on image data transmitted from those CCD cameras, wherein a computer unit computes absolute positions of those CCD cameras based on horizontal and vertical angles of respective reference-point members and a pair of points of the reference bar against light axes of the installed CCD camera and also based on the distance between a pair of points of the reference bar, and then, the computer unit computes positions of respective measurable points based on processed data as reference. Whenever those image data vary, the computer unit correctively computes absolute positions of the installed CCD cameras.