Abstract: A gas laser comprises a pair of elongated electrodes arranged to define a discharge region between two opposing surfaces of said elongated electrodes, wherein the discharge region defines a longitudinal axis, a wide axis and a narrow axis. The gas laser further includes a lasing gas disposed in said discharge region and an excitation means for energizing the electrodes to excite the lasing gas. A first mirror is arranged in front of a first end of the pair of elongated electrodes, wherein the first mirror is spaced apart from the first end along the longitudinal axis by a first distance, and a second mirror is arranged in front of a second end of the pair of elongated electrodes. Moreover, the two opposing electrode surfaces define an electrode curvature, respectively, that is adapted such that a wave front of the a fundamental transverse radiation mode with respect to the narrow axis substantially coincides with a mirror curvature of the first mirror at the first distance.

Abstract: The present invention relates to laser devices with increased cooling capability by means of largely extended cooling surfaces contacting the laser active medium. According to the present invention there is provided a laser device comprising a large active volume in conjunction with a compact structure of the device and outputting single mode radiation. The laser device according to the present invention comprises the following features. A laser active medium, an optical resonator system defining an optical axis, exciting means for exciting said laser active medium and enabling a stimulated emission of radiation of said laser active medium, and cooling means, having first and second cooling elements arranged in spaced opposing relationship with surfaces facing each other, wherein said laser active medium is provided between said cooling elements along said optical axis.