US5200854A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Large-screen projection-type display
Assignee: Hitachi Ltd
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Filing: 1992-02-20
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Granted: 1993-04-06
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Expires: 2012-02-20
Abstract
Abstract The object of the invention is to provide a large-screen projection-type display using a transmission-type screen, wherein the transmission-type screen is formed of two or more sheets 4, 7, is tilted toward the viewer's side with a small gap kept between the sheets, and is stable relative to the temperature and moisture change of the environment. The front sheet 4 provided on the viewer's side and the Fresnel sheet 7 provided on the projection source side are tilted forward by about 7° toward the viewers. The springs 10 are extended through wires 9 to exert the tension on the front sheet 4 in the vertical direction. At the same time, the springs exert a pressure on the Fresnel sheet 7 in the vertical direction.
Inventors
- 👤 Masanori Ogino
- 👤 Yoshiaki Iwahara
- 👤 Shuichi Sakamoto
- 👤 Yukihiro Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:50
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/58; G03B21/60; G03B21/62; G03B21/625
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
108 words
A large-screen projection-type display using a transmission-type screen, wherein s id transmission-type screen is formed of, at least, two sheets, or a first sheet provided on the viewer's side, and a second sheet provided on the projection source side far from said first sheet, both of said sheets are tilted toward the viewers by about 0.04 radian or above relative to the vertical direction, said first sheet is tensioned at least in the vertical direction, said second sheet has a warp of more than about 2.4 times as large as its thickness, and said first sheet and said second sheet are kept spaced about 7 mm or below.
Claim 2
Dependent Claim
108 words
A large-screen projection-type display using a transmission-type screen, wherein s id transmission-type screen is formed of, at least, two sheets, or a first sheet provided on the viewer's side, and a second sheet provided on the projection source side far from said first sheet, both of said sheets are tilted toward the viewers by about 0.04 radian or above relative to the vertical direction, said first sheet is tensioned at least in the vertical direction, said second sheet has a warp of more than about 2.4 times as large as its thickness, and said first sheet and said second sheet are kept spaced about 7 mm or below.
Claim 3
Dependent Claim
32 words
A large-screen projection-type display according to claim 1, wherein said first sheet has spring means provided at its upper and lower ends so that said tension is applied by said spring means.
Claim 4
Dependent Claim
44 words
A large-screen projection-type display according to claim 1, wherein said first sheet has a shelf member provided at least at the lower end, and said tension in said first sheet is applied by exerting the weight of said second sheet on said shelf member.
Claim 5
Dependent Claim
30 words
A large-screen projection-type display according to claim 2, wherein said spring means exert not only said tension on said first sheet but also a pressure in the horizontal direction thereon.
Claim 6
Dependent Claim
33 words
A large-screen projection-type display according to claim 2, wherein said spring means exert not only said tension on said first sheet but also a pressure on said second sheet in the vertical direction.
Claim 7
Dependent Claim
106 words
A large-screen projection-type display using a transmission-type screen, wherein said transmission-type screen is formed of, at least, two sheets, or a front sheet provided on the viewer's side and a Fresnel sheet provided on the projection source side far from said front sheet, both said sheets are tilted toward the viewers by about 0.04 radian or above relative to the vertical direction, said front sheet is tensioned at least in the vertical direction, said Fresnel sheet has a warp of more than about 2.4 times as large as its thickness, and said front sheet and said Fresnel sheet are kept spaced about 7 mm or below.
Claim 8
Dependent Claim
106 words
A large-screen projection-type display using a transmission-type screen, wherein said transmission-type screen is formed of, at least, two sheets, or a front sheet provided on the viewer's side and a Fresnel sheet provided on the projection source side far from said front sheet, both said sheets are tilted toward the viewers by about 0.04 radian or above relative to the vertical direction, said front sheet is tensioned at least in the vertical direction, said Fresnel sheet has a warp of more than about 2.4 times as large as its thickness, and said front sheet and said Fresnel sheet are kept spaced about 7 mm or below.
Claim 9
Dependent Claim
32 words
A large-screen projection-type display according to claim 6, wherein said front sheet has spring means provided at its upper and lower ends so that said tension is applied by said spring means.
Claim 10
Dependent Claim
44 words
A large-screen projection-type display according to claim 6, wherein said front sheet has a shelf member at least at its lower end so that said tension in said front sheet is applied by exerting the weight of said Fresnel sheet on said shelf member.
Claim 11
Dependent Claim
30 words
A large-screen projection-type display according to claim 7, wherein said spring means exerts not only said tension on said front sheet but also a pressure in the horizontal direction thereon.
Claim 12
Dependent Claim
33 words
A large-screen projection-type display according to claim 7, wherein said spring means exerts not only said tension on said front sheet but also a pressure on said Fresnel sheet in the vertical direction.
References Cited (Backward Citations)
US3037424A
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US4536056A
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US4406519A
Cited
US4574506A
Cited
US5011277A
Cited
US5127722A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-04-05 | 1996-10-05 | 1997-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-04-05 | 2000-10-05 | 2001-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-04-05 | 2004-10-05 | 2005-04-06 | $7700.00 | Window Closed / Lapsed |