Patent · US Expired

Laser processing power output stabilization apparatus and method employing processing position feedback

US6172325A · kind A · utility

78Cited by
9References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 10, 1999
Grant dateJan 9, 2001
Priority date
Expiry dateFeb 10, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70725
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A Q-switched solid state laser system (24) operates in a pulse processing control system (10) that employs an autopulse mode and a pulse-on-position mode to stabilize the pulse-to-pulse laser energy delivered to a workpiece (20) that is moved by an X-Y positioner (18). In the autopulse mode, laser pulses are emitted at a near maximum PRF, but the pulses are blocked from reaching the workpiece by an external modulator (28, 32), such as an acousto-optic modulator ("AOM") or electro-optic modulator (also referred to as a Pockels cell). In the pulse-on-position mode, the laser emits a pulse in response to the positioner moving to a location on the workpiece that coincides with a commanded coordinate location. The processing control system delivers a stream of coordinate locations, some requiring processing, at a rate that moves the positioner and triggers the laser at about the near maximum PRF. The pulse processing control system sets the AOM to a transmissive state whenever a coordinate location requiring processing is commanded and otherwise sets the AOM to a blocking state. This pulse timing technique provides a nearly constant interpulse period for the laser, thereby improving its…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.