| 摘要 |
PURPOSE: To provide a small-sized and light weight optical head with less number of parts and formable at a low cost. CONSTITUTION: A distorted image of a beam is obtained by tilting the beam to the normal of an inlet surface 13 of a prism 18 being a base of an isosceles prism 18. This prism 18 functions as a polarizing beam splitter also, and then, the inlet surface 13 is polarization-division-processed, and incident light that polarization is oriented according to the minor axis of an ellipse is transmitted perfectly by the processing, and the 90 deg. polarized light returning after reflected by a surface of a disk 4 is reflected perfectly. |
