Controlling laser beam parameters by crystal shifting

US10312659B1 · kind B1 · utility

Assignee

• Coherent LaserSystems GmbH & Co. KG · DE

Inventors

• Guenter Hollemann · Jena, DE
• Axel Kneip · Kiel, DE

Key dates

• Filing date: Mar 20, 2018
• Grant date: Jun 4, 2019
• Expiry date: Mar 20, 2038

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S3/005
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

This disclosure provides methods and apparatuses which advantageously stabilize beam parameters and elongate crystal lifetime. In one aspect, a UV laser apparatus includes a non-linear crystal, a laser source, a beam-crystal displacer, a beam parameter monitor, and a laser control unit. The laser source directs a source beam to the non-linear crystal to produce a UV beam and the beam-crystal displacer shifts the non-linear crystal relative to the source beam at a plurality of shift speeds. The beam parameter monitor measures the UV beam and outputs a measurement of a beam parameter. The laser control unit: receives the measurement; determines, based on the measurement, an adjustment in shift speed that steers the beam parameter toward a target value; and outputs the adjustment to the beam-crystal displacer.