| 摘要 |
PURPOSE:To enable a laser beam to be uniform widthwise in intensity by a method wherein a laser beam is made to be larger in beamwidth through a beam scanner provided with a rotating mirror and a concave cylindrical mirror and the beam scanner is regulated in a rotating angular velocity. CONSTITUTION:A laser beam A passes through a first sherical mirror 5 and a second spherical mirror 6, then is shrunk to have a diameter (c) on the outlet side of the second spherical mirror 6, and made to be parallel laser beam high in energy density. Next, the laser beam A is expanded in fan shape with an angle 2theta which is two times the rotation angle theta of rotating mirror 8 by a beam scanner 7, moreover passes a convex cylindrical minor 9 and a concave cylindrical mirror 10, expanded at the outlet side of the mirror 10 to be a laser beam B b in beamwidth, that is, expanded to be (b) in cross-sectional major diameter with the cross-sectional mirror diameter (c) being unchanged, so that the laser beam B is parallel and an ellipse in cross-section. And, a laser beam can be uniformed widthwise in intensity distribution by regulating a beam scanner. |
