Laser processing with acoustic monitoring

Abstract

An apparatus for laser processing a workpiece includes a laser processing head that directs a laser beam to the workpiece and focuses the laser beam, and a collection of three or more acoustic sensors attached to the laser processing head. The acoustic sensors are distributed about an optical axis of the laser beam as incident on the workpiece. Mounting of the acoustic sensors to the laser processing head is advantageous for serial processing of multiple workpieces and of multiple different portions of a workpiece. Alignment between the acoustic sensors and the laser beam is maintained during movement of the laser processing head. Electrical signals produced by each acoustic sensor in response to acoustic signals incident thereon may be amplified and/or spectrally filtered. Both amplification and spectral filtering may be independently adjustable for each acoustic sensor. The acoustic sensors may be sensitive to acoustic frequencies higher than 20 kilohertz.

Dependencies are inferred from the claim text.