Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
184 words
An image display apparatus comprising an image display device for displaying an image, and an ocular optical system for projecting the image displayed by said image display device and for leading the projected image to an observer's eyeball, said ocular optical system including a first optical element and a second optical element, said first optical element having at least three surfaces, wherein a space formed by said at least three surfaces is filled with a medium having a refractive index larger than 1, said at least three surfaces being, in order in which light rays pass according to backward ray tracing from said observer's eyeball toward said image display device, a first surface which serves as both a refracting surface and an internally reflecting surface, a second surface which is a reflecting surface of positive power facing said first surface and decentered or tilted with respect to an observer's visual axis, and a third surface which is a refracting surface closest to said image display device, said second optical element having refracting action and being disposed between said first surface and said observer's eyeball.
Claim 2
Dependent Claim
184 words
An image display apparatus comprising an image display device for displaying an image, and an ocular optical system for projecting the image displayed by said image display device and for leading the projected image to an observer's eyeball, said ocular optical system including a first optical element and a second optical element, said first optical element having at least three surfaces, wherein a space formed by said at least three surfaces is filled with a medium having a refractive index larger than 1, said at least three surfaces being, in order in which light rays pass according to backward ray tracing from said observer's eyeball toward said image display device, a first surface which serves as both a refracting surface and an internally reflecting surface, a second surface which is a reflecting surface of positive power facing said first surface and decentered or tilted with respect to an observer's visual axis, and a third surface which is a refracting surface closest to said image display device, said second optical element having refracting action and being disposed between said first surface and said observer's eyeball.
Claim 3
Dependent Claim
16 words
An image display apparatus according to claim 1, wherein said second optical element has positive power.
Claim 4
Dependent Claim
17 words
An image display apparatus according to claim 2, wherein said second optical element is a positive lens.
Claim 5
Dependent Claim
19 words
An image display apparatus according to claim 1 or 2, wherein said second optical element is a cemented lens.
Claim 6
Dependent Claim
24 words
An image display apparatus according to claim 1 or 2, wherein said second optical element is a special prism comprising two decentered optical surfaces.
Claim 7
Dependent Claim
24 words
An image display apparatus according to claim 1, wherein said second optical element is decentered or tilted with respect to said observer's visual axis.
Claim 8
Dependent Claim
23 words
An image display apparatus according to claim 1, wherein internal reflection at the first surface of said first optical element is total reflection.
Claim 9
Dependent Claim
26 words
An image display apparatus according to claim 1, wherein the first surface of said first optical element has an internally reflecting region which has been mirror-coated.
Claim 10
Dependent Claim
29 words
An image display apparatus according to claim 1, wherein at least one of the first, second and third surfaces of said first optical element is a decentered aspherical surface.
Claim 11
Dependent Claim
28 words
An image display apparatus according to claim 9, wherein at least one of the first, second and third surfaces of said first optical element is an anamorphic surface.
Claim 12
Dependent Claim
81 words
An image display apparatus according to claim 10, which satisfies the following condition: R.sub.y2 /R.sub.x2 ≧1 (1) where, assuming that a vertical plane containing said observer's visual axis is defined as a YZ-plane, and a horizontal plane containing said observer's visual axis is defined as an XZ-plane, R y2 is a radius of curvature in the YZ-plane of the second surface of said first optical element, and R x2 is a radius of curvature in the XZ-plane of said second surface.
Claim 13
Dependent Claim
30 words
An image display apparatus according to claim 1, wherein the first surface of said first optical element is a reflecting surface having a convex surface directed toward said second surface.
Claim 14
Dependent Claim
34 words
An image display apparatus according to claim 1, wherein at least one of the first and third surfaces of said first optical element is tilted or decentered with respect to said observer's visual axis.
Claim 15
Dependent Claim
39 words
An image display apparatus according to claim 1, which satisfies the following condition: 5°<α<30° (2) where α is an angle formed between a line normal to the second surface of said first optical element and an axial principal ray.
Claim 16
Dependent Claim
28 words
An image display apparatus according to claim 1, 9 or 10, wherein said image display device has a display surface tilted with respect to said observer's visual axis.
Claim 17
Dependent Claim
32 words
An image display apparatus according to claim 1, 9 or 10, further comprising means for positioning both said image display device and said ocular optical system with respect to an observer's head.
Claim 18
Dependent Claim
47 words
An image display apparatus according to any one of claims 1 to 16, further comprising means for supporting both said image display device and said ocular optical system with respect to an observer's head so that said image display apparatus can be fitted to said observer's head.
Claim 19
Dependent Claim
29 words
An image display apparatus according to claim 1, 9 or 10, further comprising means for supporting at least a pair of said image display apparatuses at a predetermined spacing.
Claim 20
Dependent Claim
23 words
An image display apparatus according to claim 1, 9 or 10, wherein said ocular optical system is used as an imaging optical system.