The cooling of the outer surface of the rod or other solid active element of a solid state laser is improved by causing coolant to travel in a plurality of, preferably streamline, helical flows extending around this surface in contact with it. The respective longitudinal components of a pair of the helical flows preferably extend in opposite directions along the surface to improve the uniformity of cooling.
A hand-held laser device includes a casing formed with a substantially hollow interior space and having a laser emitter thereinside. The laser emitter is formed with an exciting lamp and a laser rod. A source generating a stream of gaseous coolant is provided within the interior space. A fluid cooling arrangement at least partially surrounding the laser rod is disposed within the stream of gaseous coolant for heat removal therefrom.
