US5596433A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Head-mounted image display apparatus having a prism with an aspherical surface
Assignee: Olympus Corp
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Filing: 1994-04-26
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Granted: 1997-01-21
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Expires: 2014-04-26
Abstract
Abstract An image display apparatus, for example, a head-mounted image display apparatus, which has a compact magnifying optical system designed so that the horizontal angle of view is as wide as 30° or more, and yet the most off-axis distortion can be reduced to about 5%. The image display apparatus has a display device (D), an optical system (L+R) for projecting the content of information displayed by the display device (D) on an observer's eyeball as a enlarged virtual image without effecting image formation in the optical path, and an optical axis bending device (P) for bending the optical axis of the optical system. The optical axis bending device (P) is a beam splitter prism having a semitransparent surface. The beam splitter prism has an aspherical surface (r 11 ) constituting a surface thereof which faces the display device (D). The aspherical surface (r 11 ) is shaped so that the power thereof changes from a relatively positive value to a relatively negative value as the distance from the optical axis of the prism increases toward the periphery thereof.
Inventors
- 👤 Osamu Konuma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:04
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/10; G02B27/1066; G02B27/01; G02B27/017; G02B27/0172; G02B27/14; G02B27/144; G02B27/0101; G02B2027/011; G02B2027/0178
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
86 words
A head-mounted image display apparatus comprising: an image display device for displaying an image, and an ocular optical system for forming an exit pupil to lead said image into an observer's eyeball, wherein said ocular optical system includes a prism having a predetermined surface having both reflecting and transmitting functions and being provided at a tilt with respect to an optical axis of light emitted from said image display device, said prism having an aspherical surface on the side thereof which faces said image display device.
Claim 2
Dependent Claim
86 words
A head-mounted image display apparatus comprising: an image display device for displaying an image, and an ocular optical system for forming an exit pupil to lead said image into an observer's eyeball, wherein said ocular optical system includes a prism having a predetermined surface having both reflecting and transmitting functions and being provided at a tilt with respect to an optical axis of light emitted from said image display device, said prism having an aspherical surface on the side thereof which faces said image display device.
Claim 3
Dependent Claim
58 words
A head-mounted image display apparatus comprising: an image display device for displaying an image, and an ocular optical system for forming an exit pupil to lead said image into an observer's eyeball, wherein said ocular optical system includes a prism having a first surface disposed to face said image display device, said first surface being an aspherical surface.
Claim 4
Dependent Claim
58 words
A head-mounted image display apparatus comprising: an image display device for displaying an image, and an ocular optical system for forming an exit pupil to lead said image into an observer's eyeball, wherein said ocular optical system includes a prism having a first surface disposed to face said image display device, said first surface being an aspherical surface.
Claim 5
Dependent Claim
35 words
An apparatus according to claim 1 or 2, wherein said aspherical surface is shaped so that negative power becomes stronger as the distance from an optical axis of said prism increases toward the periphery thereof.
Claim 6
Dependent Claim
106 words
An image display apparatus according to claim 1 or 2, wherein the configuration Z(y) of said aspherical surface satisfies the following conditions (6) and (7): Z=(y.sup.2 /r)/[1+{1-(1+k)(y.sup.2 /r.sup.2)}.sup.1/2 ]+Ay.sup.4 +By.sup.6 +Cy.sup.8 +Dy.sup.10 ( 6) 0.5×.sup.-4 <|A|<0.4×10.sup.-3( 7) where Z is a distance measured from the vertex of said aspherical surface in the direction of an optical axis of said prism; y is a distance measured from the vertex in a direction perpendicular to the optical axis; r is a radius of curvature of the vertex; k is a conical constant; and A, B, C and D are 4th-, 6-th, 8-th and 10-th order aspherical coefficients, respectively.
Claim 7
Dependent Claim
112 words
An apparatus according to claim 1 or 2, wherein the configuration Z(y) of said aspherical surface satisfies the following conditions (6) and (8): Z=(y.sup.2 /r)/[1+{1-(1+k)(y.sup.2 /r.sup.2)}.sup.1/2 ]+Ay.sup.4 +By.sup.6 +Cy.sup.8 +Dy.sup.10 ( 6) 0.05<|dz/dy.sub.c |<0.5 (8) where Z is a distance measured from the vertex of said aspherical surface in the direction of an optical axis of said prism; y is a distance measured from the vertex in a direction perpendicular to the optical axis; r is a radius of curvature of the vertex; k is a conical constant; A, B, C and D are 4th-, 6-th, 8-th and 10-th order aspherical coefficients, respectively; and the suffix" c " indicates a chief ray.
Claim 8
Dependent Claim
31 words
An image display apparatus according to claim 1 or 2, wherein said ocular optical system has a focal length f (mm) which satisfies the following condition (1): 20<f<60 [mm] (1). 7.
Claim 9
Dependent Claim
27 words
An image display apparatus according to claim 1, wherein a positive lens is provided between the exit pupil of said ocular optical system and said predetermined surface.
Claim 10
Dependent Claim
24 words
An apparatus according to claim 2, wherein a positive lens is provided between the exit pupil of said ocular optical system and said prism.
Claim 11
Dependent Claim
41 words
An apparatus according to claim 7 or 8, which satisfies the following condition (2): 0.2<|.o slashed..sub.1 /.o slashed.|<0.5 (2) where .o slashed. 1 is the power of said positive lens, and .o slashed. is the power of the entire optical system.
Claim 12
Dependent Claim
38 words
A head-mounted image display apparatus according to claim 1, wherein said ocular optical system further includes a concave reflecting surface which is disposed to face said predetermined surface and has a refractive index which is larger than 1.
Claim 13
Dependent Claim
48 words
A head-mounted image display apparatus according to claim 2, wherein said ocular optical system comprises a predetermined surface capable of reflecting and transmitting a bundle of light rays emitted from said image display device, and a concave reflecting surface having a refractive index which is larger than 1.
Claim 14
Dependent Claim
75 words
A head-mounted image display apparatus according to claim 10 or 11, wherein said predetermined surface is provided in a direction of propagation of the bundle of light rays emitted from said image display device, and said concave reflecting surface faces said predetermined surface so that a turn-back optical path for a round-trip travel of the bundle of light rays from said image display device is formed between said predetermined surface and said concave reflecting surface.
Claim 15
Dependent Claim
52 words
A head-mounted image display apparatus according to claim 10 or 11, wherein the image that is formed by said image display device is corrected for aberrations by aspherical surface and said concave reflecting surface so that said image can be observed at a horizontal field angle which is not smaller than 30°.
Claim 16
Dependent Claim
46 words
A head-mounted image display apparatus according to claim 1 or 2, wherein said image display device and said ocular optical system are mounted on a face-mounted unit, said head-mounted image display apparatus further having a support member for retaining said face-mounted unit on an observer's head.
References Cited (Backward Citations)
US4968117A
Cited
US4859030A
Cited
US4969724A
Cited
US4969714A
Cited
JPH03191389A
Cited
US5303085A
Cited
US5278696A
Cited
US5309169A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-01-21 | 2000-07-22 | 2001-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-21 | 2004-07-22 | 2005-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-21 | 2008-07-22 | 2009-01-21 | $7700.00 | Window Closed / Lapsed |