Patent ID: 7719759
Filing Date: 2010-05-18
Classification: G02B

Abstract:
1. An imaging optical system, comprising: a first reflector, a second reflector, and a third reflector arranged on an optical path of incident ray, wherein wherein one of the first reflector and the third reflector is a convex mirror and the other is a concave mirror; and the three reflectors are positioned with respect to each-other such that, in terms of a central chief ray, which is defined as a chief ray of light beams forming an image at a center of the image plane, and further wherein, in terms of a reference plane containing three points that are the reflection point of the central chief ray on the first reflection surface, the reflection point of the central chief ray on the second reflection surface, and the reflection point of the central chief ray on the third reflection surface, when an angle formed by the central chief ray incident to the first reflector and the reference plane is represented as θ and an angle formed by the central chief ray reflected by the third reflector and the reference plane is represented as θ′, the following condition is satisfied: