| 摘要 |
PURPOSE:To reduce the height of a titled reader and to realize miniaturization for said reader, by constituting a polarizing prism with the 1st rectangular prism containing two slanting faces set to optical paths at light emitting and photodetecting sides, the 2nd rectangular prism cemented to the 1st prism and a polarizing film. CONSTITUTION:A case 12 contains a laser light source 16, a photodetecting element 22, polarizing prisms 25 and 26, etc. A polarizing prism consists of the 1st rectangular polarizing prism containing two slanting faces 25a and 25b set to optical paths at light emitting and photodetecting sides, respectively, and 2nd rectangular prism containing a bottom face 26a cemented to the face 25b, and a polarizing film attached to the cemented face. This polarizing prism is put into pierced holes 12a and 12b from a through-hole 12c of the case 12. A 1/4 wavelength plate 27 is set at the upper part of the prism. In such a way, a rectangular prism can be eliminated in comparison with a conventional case. This process can reduce the size in the height direction for an optical information reader. |
