Abstract: A method calibrates a laser processing machine by commanding a scan head to direct a laser beam to a desired position, then senses an actual position of the laser beam directly using a position sensitive detector (PSD) after the scan head is positioned. A relative position between the scan head and PSD is altered using one or more linear actuators. A position feedback loop is closed around the linear actuators so that the relative position of the laser beam on the PSD is reduced to zero. The actual position of the laser spot is then measured indirectly by encoders attached to linear axes of the laser processing machine. The actual position is stored in a memory. An error is determined as a difference between the desired position and the actual position. Compensation coefficients are determined from the error and stored for later use during operation of the laser processing machine.

Abstract: A system for calibrating a laser cutting machine includes a calibration plate arranged to simulate a workpiece; a first quad photodiode (QPD) and a second QPD for converting light including an image of a portion of a surface of the calibration plate into a plurality of electrical signals, wherein the first and the second QPDs are positioned to receive the light propagated from the surface of the calibration plate through the optical path of the laser beam; and a control system for calibrating the laser cutting machine based on the plurality electrical signals.

Abstract: A method calibrates a laser processing machine by commanding a scan head to direct a laser beam to a desired position, then senses an actual position of the laser beam directly using a position sensitive detector (PSD) after the scan head is positioned. A relative position between the scan head and PSD is altered using one or more linear actuators. A position feedback loop is closed around the linear actuators so that the relative position of the laser beam on the PSD is reduced to zero. The actual position of the laser spot is then measured indirectly by encoders attached to linear axes of the laser processing machine. The actual position is stored in a memory. An error is determined as a difference between the desired position and the actual position. Compensation coefficients are determined from the error and stored for later use during operation of the laser processing machine.

Abstract: A system for calibrating a laser cutting machine includes a calibration plate arranged to simulate a workpiece; a first quad photodiode (QPD) and a second QPD for converting light including an image of a portion of a surface of the calibration plate into a plurality of electrical signals, wherein the first and the second QPDs are positioned to receive the light propagated from the surface of the calibration plate through the optical path of the laser beam; and a control system for calibrating the laser cutting machine based on the plurality electrical signals.