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Abstract

Abstract PURPOSE:To convert easily polarized light without using a lambda/4 plate as a polarized light converting element by converting the polarized light by using a full-reflecting prism as the polarized light converting element. CONSTITUTION:The polarized light of incident light flux RPF generated from a semiconductor laser device 100 is linearly polarized light to be vertically vibrated within a surface rectangular to the light flux RPF as shown in (B) and is made parallel light flux through a collimate lens 102. The parallel light flux is made incident on the full-reflecting prism 106 through a polarized light separating optical element 104 and fully reflected twice to be turned to circularly polarized light, and made incident on a disk 110 through an objective 110. The reflected light flux RPF reflected by the disk 110 is reduced to a circularly polarized light reversed to the RPF in rotation, as shown by the figure (B), and said circularly polarized light is made horizontally linearly polarized light as shown in (C) through the full-reflecting prism 106. The linearly polarized light is separated by the polarized light separating optical element 104 and the separated component is made incident on a photoelectric conversion element 116. Thus, the light can be easily converted in polarization.

Inventors

• 👤 Hiroshi Kokado
• 👤 古角　博司

Bibliographic Details