Pointing stability of copper vapor laser with novel off-axis unstableresonator,

摘要

Abstract: Off-axis unstable resonators are used in copper vapor lasers to obtain low divergence beam. In the common resonator design, the edge of a small diameter convex mirror is used as the front mirror. The beam pointing of such a laser is strongly dependent on the operation conditions of the head, and thus day to day fluctuations are observed. In a new cavity design, the convex mirror is coupled via the edge of a flat scraper mirror. As a result, a pointing stability as small as 0.2 mrad was observed. It is shown that in lasers with short inversion life time and high gain geometrical considerations may explain temporal and spatial properties of the laser output. The spatial and temporal properties of a 28 mm diameter CVL are also described, and the mode of operation of the laser is discussed. !