电兴奋扩散冷却的高功率激光器（10），布置有两个以小的距离彼此，光波导形成板（16，18）的宽度为它们的间隔的倍数，并且其封闭在它们之间的自由流动的放电空间;以及光学谐振腔， 波导的谐振镜（38，44）在两端（22,24）被布置成提高这样一种方式，良好的可聚焦激光束产生的，所以建议共振器为光学不稳定谐振器（50）具有纵向的谐振器 （52）延伸，并且，以所述谐振器轴线（52）的横向尺寸（54）到至少一个具有光学路径和横向尺寸横向于波导的纵向方向（20）和（近似平行于壁表面16出射的激光束（55） ，18）。

To an electrically excited diffusion cooled high-power laser (10) arranged with two at a small distance from each other, an optical waveguide-forming panels (16, 18) whose width is a multiple of their spacing and which enclose a flow-free discharge space between them, and with an optical resonator, the resonator mirrors (38, 44) at both ends (22, 24) of the waveguide are arranged to improve such a way that a well-focusable laser beam produced, it is proposed that the resonator is an optically unstable resonator (50) having a lengthwise of a resonator (52) extends and to the resonator axis (52) transverse extension (54) up to at least one exiting laser beam (55) having optical path and that the transverse extension transverse to a longitudinal direction (20) of said waveguide and approximately parallel to the wall surfaces (16 , 18).