System and method for calibrating laser processing machines

US9718146B2 · kind B2 · utility

Assignee

• Mitsubishi Electric Research Laboratories, Inc. · US

Inventors

• Abraham Goldsmith · Boston, US
• Scott A. Bortoff · Brookline, US
• Vijay Shilpiekandula · Cambridge, US
• Alan Sullivan · Middleton, US
• William S. Yerazunis · Acton, US
• John C. Barnwell, III · Leominster, US

Key dates

• Filing date: Jun 3, 2013
• Grant date: Aug 1, 2017
• Expiry date: Oct 27, 2034

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S3/0014
• WIPO field: Measurement
• WIPO sector: Instruments

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.