| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a new laser optical element having less beam loss by combining a total reflection mirror function and a toroidal mirror function.SOLUTION: A block having a beam incident surface (ABB'A plane), an emission surface (ACC'A' plane) and a reflection surface (BCC'B' plane) is cut out of a highly transparent solid, as shown in FIG. 1, to polish the reflection surface to be a toroidal surface. The refractive index of a base material is selected so that reflection in the solid becomes total reflection. The toroidal surface has a meridional plane curvature radius of Rh=2fh/cos(alpha) and a sagittal plane curvature radius of Rv=2fvcos(alpha), when a laser beam enters the center of the reflection surface (point o) at an incidence angle alpha, where a focal distance is fh in the surface including the beam, and a focal distance in a direction perpendicular to the focal distance fh is fv.</p> |
