| 摘要 |
PROBLEM TO BE SOLVED: To precisely adjust the focus of a laser light source which emits plural laser light fluxes. SOLUTION: A collimator lens 11 is finely adjusted in the direction of an optical axis so that first laser light is best focused on a plane to be irradiated 15 in a meridional cross section and furthermore, a laser light emitting element 10 is rotationally adjusted to be the best focus. By repeating the fine adjustment of the collimator lens 11 and the rotational fine adjustment of the laser light emitting element 10 several times, the first and second laser light beams become the best focusing condition in the medional cross section. At this time, although the laser light in the sagittal cross section is light flux slightly widened by the collimator lens 11, a cylindrical lens 12 is finely adjusted in the direction of the optical axis to convert the light to converging light and to adjust focussing on the plane to be irradiated 15. |
