US4294515A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Virtual image display apparatus
Assignee: BMCO Inc EDINA MN A CORP OF
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Filing: 1979-03-23
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Granted: 1981-10-13
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Expires: 1999-03-23
Abstract
Abstract A virtual image display device for alpha-numeric and pictorial information. A concave spherical mirror segment magnifies and reflects an image from an image source. The image source is mounted between the focus of the mirror and the said mirror and parallel to its optical axis. The virtual image thereby formed is visible to the viewer in front of the mirror. In related embodiments, the concave mirror segment can be made partially reflective and placed in front of a camera lens to allow a camera to photograph through it. A planar mirror can also be included to fold the light path of the display and thereby reduce the size of the apparatus.
Inventors
- 👤 Arthur Kaufman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:52
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/10; G02B27/14; G02B27/144; G02B27/01; G02B27/0101; G02B27/1006; G02B27/141; G09; G09F; G09F19/00; G09F19/12; G09F19/16; B; B60; B60K; B60K2360/00; B60K2360/20; B60K2360/33; B60K2360/334; G02B2027/0118; G02B2027/0138; G02B27/0149; G02B2027/0154; G02B2027/0169
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
83 words
A virtual image display apparatus comprising a mirror in the shape of a substantially concave segment of a hemisphere said spherical mirror having an optical axis and a focus, an image source means for said mirror segment, and an image display face on said image source disposed substantially perpendicular to said optical axis but located off said axis and substantially on the same side of the axis as the line of sight of an observer and between said focus and said mirror segment.
Claim 2
Dependent Claim
83 words
A virtual image display apparatus comprising a mirror in the shape of a substantially concave segment of a hemisphere said spherical mirror having an optical axis and a focus, an image source means for said mirror segment, and an image display face on said image source disposed substantially perpendicular to said optical axis but located off said axis and substantially on the same side of the axis as the line of sight of an observer and between said focus and said mirror segment.
Claim 3
Dependent Claim
18 words
A virtual image display apparatus according to claim 1 wherein said mirror segment is a partially reflective mirror.
Claim 4
Dependent Claim
48 words
A virtual image display apparatus according to claim 1 wherein a partially reflective planar mirror is angularly positioned between said mirror segment and said image source to receive light reflected by the mirror segment and direct it in a path across the optical axis of said mirror segment.
Claim 5
Dependent Claim
58 words
A virtual image display apparatus according to claim 1 wherein a fully reflective mirror is placed substantially in front of said image source laterally displaced from the concave mirror segment and substantially parallel to the light emitting image display face of said image source and wherein the said image display face is directed away from said mirror segment.
Claim 6
Dependent Claim
19 words
A virtual image display apparatus according to claim 1 wherein said image source means is a cathode ray tube.
Claim 7
Dependent Claim
21 words
A virtual image display apparatus according to claim 1 wherein said image source means is a thin film cathode ray tube.
Claim 8
Dependent Claim
20 words
A virtual image display apparatus according to claim 1 wherein said image source means is a liquid crystal display apparatus.
Claim 9
Dependent Claim
20 words
A virtual image display apparatus according to claim 1 wherein said image source means is a light emitting diode array.
Claim 10
Dependent Claim
18 words
A virtual image display device according to claim 1 wherein said image source means is an electroluminescent panel.
Claim 11
Dependent Claim
19 words
A virtual image display device according to claim 1 wherein said image source means is a tungsten filament projector.
Claim 12
Dependent Claim
20 words
A virtual image display device according to claim 1 wherein said image source means is a gaseous plasma discharge cell.
Claim 13
Dependent Claim
20 words
A virtual image display device according to claim 1 wherein said image source is a back illuminated film or transparency.
Claim 14
Dependent Claim
21 words
A virtual image display device according to claim 1 wherein said image source means is a front illuminated partially reflecting original.
Claim 15
Dependent Claim
15 words
A virtual image display device according to claim 1 wherein said mirror segment is dichroic.
Claim 16
Dependent Claim
17 words
A virtual image display apparatus according to claim 3 wherein said partially reflective planar mirror is dichroic.
Claim 17
Dependent Claim
69 words
A virtual image display apparatus according to claim 1 wherein said image source is slidably carried by a support located between said mirror segment and said focus, whereby said image source may be moved so as to decrease or increase the degree to which its image is magnified by the virtual image display apparatus without changing the vertical position of the virtual image with respect to the mirror segment.
Claim 18
Dependent Claim
21 words
A virtual image display apparatus according to claim 4 in which the fully reflective mirror is a curved front surface mirror.
Claim 19
Dependent Claim
19 words
A virtual image display apparatus according to claim 4 in which the fully reflective mirror is a planar mirror.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-12 | 1985-04-13 | 1985-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-12 | 1989-04-13 | 1989-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-12 | 1993-04-13 | 1993-10-13 | $7700.00 | Window Closed / Lapsed |