Optical component cleanliness and debris management in laser micromachining applications

US8320424B2 · kind B2 · utility

Assignee

• ELECTRO SCIENTIFIC INDUSTRIES, INC. · US

Inventors

• Bryan Bolt · Beaverton, US
• David Martin Hemenway · Beaverton, US
• Mark Kosmowski · Tigard, US
• A. Grey Lerner · Portland, US
• Brady Nilsen · Beaverton, US
• Richard Pope · Tipp City, US

Key dates

• Filing date: Nov 30, 2006
• Grant date: Nov 27, 2012
• Expiry date: Aug 31, 2031

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B23K26/142
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

Preferred embodiments of a purge gas port, laser beam attenuating input window, and laser shutter constitute subsystems of a UV laser optical system in which a laser beam is completely enclosed to reduce contamination of the optical system components. Purge gas is injected through multiple locations in a beam tube assembly to ensure that the optical component surfaces sensitive to contamination are in the flow path of the purge gas. The input window functions as a fixed level attenuator to limit photopolymerization of airborne molecules and particles. Periodically rotating optical elements asymmetrically in their holders reduces burn damage to the optics.