| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an easily manufacturable wavelength plate having satisfactory polarizing conversion efficiency with no variability, a polarizing conversion element, an illumination optical system, and an image display device. <P>SOLUTION: This wavelength plate includes; a first crystal plate in which a crystal optical axis is inclined to a main surface; and a second crystal plate in which a crystal optical axis is inclined to a main surface superimposed to the main surface of the first crystal plate. Then, this wavelength plate is configured such that an angle made by the optical axis of the first crystal plate and the optical axis of the second crystal plate is 45 degrees in a front sight viewed from a direction which is vertical to the main surface, and that the optical axis of the first crystal plate is made in parallel with the optical axis of the second crystal plate in an upper sight viewed from a direction which is parallel with the main surface. Also, a polarizing conversion element, an illumination optical system, and an image display device are configured by using this wavelength plate. <P>COPYRIGHT: (C)2012,JPO&INPIT |
