Patent ID: 6462881
Filing Date: 2002-10-08
Classification: G02B

Abstract:
An image display apparatus comprising:a light source for illumination; a reflection type image display device adapted to display an image by reflecting a light beam from said light source; and a viewing optical system for leading the image displayed by said reflection type image display device to an observer; said viewing optical system having at least a first prism having at least a part thereof interposed in an optical path between said light source and said reflection type image display device; said light source and said reflection type image display device being so positioned that an illuminating light beam from said light source is applied to a display surface of said reflection type image display device after passing through at least a part of said first prism; wherein said first prism has: a first prism entrance surface through which an image display light beam reflected from said reflection type image display device enters said first prism; at least one first prism first reflecting surface for reflecting the light beam entering said first prism; and a first prism exit surface through which the light beam entering said first prism exits said first prism; wherein at least one of said first prism entrance surface, said first prism exit surface and said first prism first reflecting surface has a curved surface configuration that gives a power to a light beam; and wherein a harmful light eliminating member is provided in an illuminating light path extending from said light source to said reflection type image display device in a vicinity of said light source to eliminate harmful light resulting from branching off a part of the light beam emitted from said light source from said illuminating light path when it passes through said first prism.