Patent ID: 7929219
Filing Date: 2011-04-19
Classification: A61B,G02B

Abstract:
1. An optical element rotationally symmetric around a central axis and formed by a transparent medium having a refractive index greater than 1, wherein: the transparent medium includes: a flux of light entering the transparent medium has a side view optical path and a direct view optical path therein and goes into the transparent medium to proceed along the side view optical path by way of the first transmissive surface so as to be reflected to the side opposite to the image plane by the first reflective surface and then to the image plane side by the second reflective surface to form an optical path before going out from the transparent medium to the outside at the image plane side by way of the second transparent surface in the order of forward ray tracing and also along the direct view optical path by way of the third transmissive surface to form another optical path before going out from the transparent medium into the outside at the image plane side by way of the fourth transmissive surface also as viewed in the order of forward ray tracing.