摘要 |
A gas laser of the type in which gas is impelled transversely through a region where lasing of the flowing gas occurs, employs a crossfield blower to propel the gas around a closed loop. The crossfield blower has an elongate impeller that is substantially the same length as the lasing region. The impeller generates at least one vortex in the gas flow. A part of that vortex is situated outside the path of the main gas flow to the lasing region. To remove heat from the gas without appreciably interfering with the main gas flow to the lasing region, cooling means are situated in that part of the vortex that is outside the path of the main gas flow to the lasing region. |