Patent ID: 7738088

Claim:
An optical method of generating calibration data for use in calibrating a part inspection system, the method comprising: supporting a calibration device having a central axis, a width and a plurality of regions which are rotationally symmetric about the axis; scanning the device with an array of planes of radiation wherein each of the planes has a width greater than the width of the device so that the device occludes each of the planes of radiation to create a corresponding array of unobstructed left and right planar portions of the planes of radiation passing by and not blocked by the supported device wherein each of the unobstructed left and right planar portions contains an amount of radiation which is representative of a respective geometric dimension of the device; measuring the amount of radiation present in each of the unobstructed left and right planar portions to obtain measurement signals; processing the measurement signals to obtain calibration data for calibrating the system without the need to measure radiation blocked or reflected by the supported device, the calibration data being capable of converting raw data to calibrated data; and storing the calibration data.