Abstract: An optical element holding and extraction device is provided. The device includes an optical element, an optical element holder having a tubular gripping portion and a tubular extraction portion connected at one end to the tubular gripping portion, and a retainer that is slideably carried on the tubular extraction portion. The diameter of the tubular extraction portion is less than the tubular gripping portion. In addition, the tubular gripping portion grips the peripheral edge of the optical clement. The device may be used in a variety of gas lasers, including excimer lasers.

Abstract: A gas laser and a dedusting unit thereof are provided. The gas laser comprises a tube containing a gas mixture including a laser gas and preferably a buffer gas. The tube preferably comprises a cylindrical inner wall. A discharge unit is inserted into the tube and has two elongated electrodes defining an electrical gas discharge gap therebetween for providing an electric gas discharge between said electrodes to generate laser light. A circulation means is included in the tube for generating a gas flow within the tube that passes through the discharge gap. A dedusting unit is mounted along the inner cylindrical wall of the tube in such a manner that only a bypass flow which is a part of the gas flow within the tube passes through the dedusting unit.

Abstract: An adjustable mounting unit for an optical element of a gas laser is provided. The typical gas laser for which the mounting unit will be used comprises a tube having a first end wall at one end and a second end wall at the other end, an optical axis extending longitudinally through the tube, and a port in the first end wall through which the optical axis passes. The mounting unit includes a rigid support structure having an aperture therein and an optical element mounted within the aperture. In addition, at least three adjustable mounting devices are used to attach the support structure to the laser tube. The mounting points are preferably selected so that they are displaced in an axial direction by substantially the same amount due to dimensional changes in the laser occurring during operation of the laser. When attached to the laser, the rigid support is spaced apart from the laser tube to allow for the adjustment of the angular positioning of the optical element.