| 摘要 |
PURPOSE:To prevent a laser output from decreasing due to a thermal lensing effect by forming a coating layer containing Ce ions on the circumferential surface of a laser rod body. CONSTITUTION:A YAG laser rod 1 is mainly composed of a rod body 2 which is a laser medium portion and a coating layer 3 which covers the circumferential surface of the rod body 2. The rod body 2 is processed from a YAG ore composed of an Nd contained YAG single crystal to which Nd ions are added. The coating layer 3 is grown from the layer of the YAG single crystal containing Ce ions on the circumferential surface of the rod body 2 which is processed by heated hot phosphoric acid. Therefore, since the Ce ions contained in the coating layer make up for the Nd ions contained in the rod body, the coating layer absorbs energy in a wavelength region from 200nm to 500nm and acts as a kind of filter, the energy which does not contribute to a laser oscillation is little converted to heat. Thus, a heat generation in the central portion of the rod is suppressed and a thermal lens effect is decreased. |
