Narrow band excimer laser with a prism-grating as line-narrowing optical element

US6795473B1 · kind B1 · utility

Assignee

• Lambda Physik AG · DE

Inventors

• Juergen Kleinschmidt · Oettingen, DE
• Thomas Schroeder · Oettingen, DE

Key dates

• Filing date: Jun 22, 2000
• Grant date: Sep 21, 2004
• Expiry date: Jun 25, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S3/1055
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An excimer or molecular fluorine laser system includes a laser chamber filled with a gas mixture at least including a halogen-containing species and a buffer gas, and multiple electrodes with the laser chamber connected to a discharge circuit energizing the gas mixture. The laser chamber is within a laser resonator generating an output beam. The resonator includes a line-narrowing package for reducing a bandwidth of the output beam. The line-narrowing package includes a grating or grism element for use with a highly reflective (HR) and/or an anti-reflective (AR) dielectric coating. The grating may serve as a resonator reflector having a dielectric HR coating. The grating may be disposed before a HR mirror and thus have a dielectric AR or HR coating when the grating is configured in transmission or reflection mode, respectively. The grating may be used as an output coupler, and may be partially reflective with or without a coating. The grism may have a dielectric AR coating on any transmissive surface and a dielectric HR coating on any reflective surface.