PROFILE MEASUREMENT APPARATUS, BY DIGITAL MOIRE TECHNIQUE, CALIBRATED TO ALLOW A PRECISE CONVERSION OF PHASE INFORMATION INTO DISTANCE MEASUREMENTS FOLLOWING SEVERAL DIRECTIONS

摘要

P THE INVENTION RELATES TO A METHOD AND APPARATUS FOR MEASURING THE PROFILE OF AN OBJECT BY INTERFEROMETRY USING A DIGITAL MOIRE TECHNIQUE. THE SYSTEM INCLUDES A MEANS 10, 20, 22 FOR CALIBRATING A SPATIAL VOLUME IN WHICH THE OBJECT IS AVAILABLE DURING THE MEASURE THAT A REFERENCE PHASE INFORMATION IS IDENTIFIED THE POSITIONS OF SEVERAL GROUPS OF POSITIONS OF SAID VOLUME, EACH OF THESE GROUPS BEING IN A DIFFERENT CALIBRATION PLAN OF A PLURALITY OF PARALLEL PLANS, AN AVERAGE 20, 22 FOR OBTAINING PHASE INFORMATION FROM THE PROFILE OF THE OBJECT IN SAID POSITIONS; A MEANS OF IDENTIFYING THE PHASE INFORMATION OBTAINED FROM SAID PROFILE; AND A MEANS OF DETERMINING THE ABSOLUTE PROFILE DISTANCE MEASURES FROM THE DIFFERENCES BETWEEN THE INFORMATION COMING FROM SAID PROFILE AND THE SAME INFORMATION GROUPS RELATING TO BOTH CALIBRATION PLANS. /P