Laser oscillator

摘要

A laser oscillator is provided, capable of preventing or reducing contamination of an optical component (4) by organic matter such as oil mist. Gas laser medium (7) in an optical resonator comprising an optical component (4) is pumped by an electric discharge (3) generated in an electric discharge tube (2) to produce a laser beam. The gas medium (7) flows at high speed in the electric discharge tube (2) incorporated in a circulating path including a blower. A part of lubrication oil of the blower is evaporated and mixed into the gas medium. Since the optical component (4) is cooled by a retaining mechanism (8) to prevent temperature rise of the component (4) and gas stagnation occurs between the optical component (4) and the electric discharge tube (2), the evaporated oil mist tends to be congealed and adhered to a surface of the optical component (4). A photocatalyst (9) arranged in the vicinity of the optical component (4) effectively decomposes and removes the oil mist. An ultraviolet ray (10) contained in light emitted by electric discharge is utilized for exciting the photocatalyst (9). A quartz tube may be adopted for supporting the photocatalyst (9) in the vicinity of the optical component (4).