NARROW BAND EXCIMER LASER

• Main Authors: WAKATA HITOSHI, SUGIDACHI ATSUSHI
• Format: Patent
• Language: English
• Published: 31.03.1992
• Subjects: BASIC ELECTRIC ELEMENTS; DEVICES USING STIMULATED EMISSION; ELECTRICITY; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PURPOSE:To obtain a narrow band excimer laser having a low coherency and adapted for drop by composing an angle formed between an optical axis of an optical resonator and a normal of a reflecting surface of an etalon, a beam diameter of a direction inclined at the optical axis to the normal, and a distance between the etalon and a partial reflecting mirror in specified relationships. CONSTITUTION:An angle theta formed between the optical axis of an optical resonator and a normal of a reflecting surface of an etalon is at least ¦theta¦>tan<-1>(x/L), (where x(cm) is a beam diameter of a direction of an inclined optical axis to the normal, and L (cm) is a distance between' the etalon and a partial reflecting mirror), and ¦theta¦< lambda/ theta.lambda (lambda is a wavelength, lambda is a necessary wavelength width, and theta is dispersing angle of necessary beam). High pressure gas of rare gas, halogen gas, etc., is sealed in a discharger 1, and when energy by discharging is applied thereto, a strong light is generated. When an optical resonator is formed of a totally-reflecting mirror 2 and a partial reflecting mirror 3 through the discharger 1, a light irradiated from the discharger is reciprocated many times in the resonator. In this case, the light is amplified by the discharger 1 to become stronger light. Part of the light is output of the resonator from the mirror 3.