| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polarizing element which absorbs no light and is compact and inexpensive by projecting one of polarized and split light beams through a phase difference layer which rotates the plane of polarization and the other through a part where the phase difference layer is not formed. SOLUTION: Light which is made incident on a birefringent layer 102 formed out of an optical anisotropic material is split into a couple of linear polarized light components (ordinary light beam 103 and extraordinary light beam 104) which have mutually crossing planes of polarization. The separation angle of the birefringent layer 102 between the two polarized components is determined by the birefringence of the material forming the birefringent layer 102 and the shape of the birefringent layer 102. The ordinary light and extraordinary light which are split by the birefringent layer 102 and have the mutually orthogonal planes of polarization are converged by a lens body 105 respectively to form focuses at mutually different positions. And, extraordinary light beam passes through the phase difference layer 106 of λ/2 formed at the focus position of the extraordinary light beam and then the plane of polarization of the light beam is rotated by 90 deg.. Consequently, the polarization directions of all light beams at the projection end of the polarizing element are aligned in one direction. |
