| 摘要 |
PROBLEM TO BE SOLVED: To provide an unstable type resonator wherein laser output and beam quality are improved by increasing the output of a downstream part in the flow direction of gas which forms laser medium. SOLUTION: In the unstable type resonator, a concave mirror (2), returning mirrors (51, 52), a convex mirror (3) and an output mirror (4) are arranged in such a manner that an optical axis of a laser light intersects almost perpendicularly the flow direction of the gas which forms the laser medium (6). In the concave mirror (2), the curvature radius of a downstream part in the flow direction of the gas to the optical axis is smaller than that of an upper stream part. |
