Patent ID: 8398241
Filing Date: 2013-03-19
Classification: G02B,G03B,G11B

Abstract:
1. A half-wave plate comprising: a single crystal plate made of an inorganic material having a birefringent property and rotatory power, wherein a polarization plane of linearly polarized light entering from an entrance surface of the crystal plate is rotated and then output from an exit surface of the crystal plate, and assuming that a phase difference of the half-wave plate is Γ, a correction amount of the phase difference is Γa, an optical axis azimuth angle formed between an optical axis projection line obtained by projecting the optical axis of the crystal plate on the entrance surface and a polarization plane of the linearly polarized light entering the entrance surface is θ, and an angle β formed between a normal line with respect to the entrance surface of the crystal plate and an optical axis of the crystal plate is set in a range of 5°≦β≦30°, the following expressions are satisfied where: A A A A A A A A A A A A A A A A where: B B B B B B B B B B B B B B B B