| 摘要 |
<p>A total reflection surface and a holographic optical element (HOE) surface are formed on the same surface (S3) in an eyepiece prism (15). In this structure, a smaller reflection angle can be set at an HOE (16) compared to a structure with the surfaces formed separately, and the HOE surface of the surface (S3) can be set in the direction parallel to a surface (S2). Thus, even in a structure in which at least a portion of the light flux of the image light fully reflected by the surface (S3) is incident on an affixing region (R1) of a hologram photosensitive material (16a), that portion of the light can be prevented from falling incident on the optical pupil (E) as ghost light. Consequently, in order to prevent the generation of ghost light, an optical path margin no longer needs to be provided between the diffraction and reflection region of the HOE (16) and the total reflection region of the image light; and the eyepiece prism (15) can be thinned by that amount. In addition, since a smaller reflection angle can be set at the HOE (16), the color dispersion caused by diffraction by the HOE (16) can also be reduced, and the image quality can be maintained.</p> |
