Narrow band excimer or molecular fluorine laser having an output coupling interferometer

US6553050B1 · kind B1 · utility

Assignee

• Lambda Physik AG · DE

Inventors

• Juergen Kleinschmidt · Oettingen, DE
• Peter Lokai · Oettingen, DE

Key dates

• Filing date: Feb 21, 2002
• Grant date: Apr 22, 2003
• Expiry date: Feb 21, 2022

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S3/225
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An excimer or molecular fluorine laser includes a discharge chamber filled with a gas mixture, multiple electrodes within the discharge chamber connected to a power supply circuit for energizing the gas mixture, and a resonator including the discharge chamber and a pair of resonator reflectors for generating an output laser beam. The resonator includes an interferometric device, which may be a resonator reflector such as an output coupling interferometer or HR reflector, or a transmissive intracavity component, including a pair of opposing reflecting surfaces tuned to produce a response maximum at a selected wavelength for narrowing a linewidth of the output laser beam. One of the pair of opposing reflecting surfaces is preferably configured such that the opposing reflecting surfaces of the interferometer have a varying optical distance therebetween over an incident beam cross-section which serves to suppress at least one side band or outer portions of the response maximum to reduce spectral purity. Preferably, this surface is non-planar, and may include a step, a recess or a raised or recessed curved portion of a quarter wavelength in height or depth, respectively, and may be cyli…