초록 ▼

An image display apparatus which enables observation of a clear image at a wide field angle, and which is extremely small in size and light in weight and hence unlikely to cause the observer to be fatigued. The image display apparatus has an image display device (7) and an ocular optical system for

An image display apparatus which enables observation of a clear image at a wide field angle, and which is extremely small in size and light in weight and hence unlikely to cause the observer to be fatigued. The image display apparatus has an image display device (7) and an ocular optical system for projecting the image of the image display device and leading the projected image to an observer's eyeball (1) The ocular optical system has, in the order of backward ray tracing, a first surface (3) which is a refracting surface, a second surface (4) which is a decentered reflecting surface of positive power, a third surface (5) which is a decentered reflecting surface, and a fourth surface (6) which is a refracting surface. At least two of the four surfaces have a finite curvature radius. A space formed by the first to fourth surfaces (3 to 6) is filled with a medium having a refractive index larger than 1. The two reflecting surfaces are disposed such that the principal ray extending from the observer's eyeball (1) to the image display device (7) does not intersect its own path in the ocular optical system. Thus, the first-order image of the image display device (7) is formed on the retina of the observer's eyeball.

대표청구항 ▼

[ What is claimed is:] [52.] A finder optical system comprising:an objective optical system for forming an object image;an image erecting optical system for erecting said object image;an ocular optical system for observing said object image; andat least one prism member, wherein said prism member ha

[ What is claimed is:] [52.] A finder optical system comprising:an objective optical system for forming an object image;an image erecting optical system for erecting said object image;an ocular optical system for observing said object image; andat least one prism member, wherein said prism member has four surfaces including:two reflecting surfaces having an action by which the image is reflected in said prism member;an entrance surface having a light-transmitting action; andan exit surface having a light-transmitting action; andwherein at least one of said two reflecting surfaces has a curved surface configuration which gives a power to a bundle of light rays, and said curved surface configuration is a rotationally asymmetric curved surface.