| 摘要 |
PURPOSE:To enable a laser resonator to be simplified in structure, reduced in cost, and easily assembled and adjusted by a method wherein an etalon is used as an output mirror. CONSTITUTION:An air-gap etalon composed of two glass plate, which are provided with a half mirror face on one of the sides respectively and arranged in parallel slightly distant from each other making the half-mirror faces confront each other, is used as a laser output mirror 5a. The half-mirror face is formed by evaporating a dielectric multilayered film on a synthetic quartz substrate, and the other side of the substrate is coated with a AR coating so as to lessen the surface in reflectivity to prevent a parasitic oscillation in a resonator. The etalon is fixed vertical to a laser optical axis, so that it is impossible to adjust an angle of insertion which is adjustable in a conventional one. Therefore, the adjustment of oscillation frequency is executed through a space adjustment mechanism provided between two glass plates of the etalon 4, or the re-adjustment of the space between the opposed glass plates can be dispensed with by fixing the space concerned after it is strictly adjusted at the time of manufacture of the etalon 4. |
