Patent US4525029A successfully refreshed from Google Patents.
US4525029A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rear projection screen
Assignee: Mitsubishi Chemical Corp
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Filing: 1983-12-22
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Granted: 1985-06-25
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Expires: 2003-12-22
Abstract
Abstract In the embodiments of the invention disclosed herein a rear projection screen has a projection surface and a viewing surface with one of the surfaces formed so as to serve as a lens to provide bright stripe portions where the light passes and dark stripe portions where no light passes. Grooves are formed in the viewing surface along the dark stripe portions and thread-like members are disposed in these grooves as light-absorbing means. The lens formed in the screen surface may be formed of lenticules grooves having total reflection surfaces provided on both sides thereof and a Fresnel lens may be provided on the projection side surface. The thread-like members may be self-adhesive and may be disposed under tension in a screen having a curved surface. A diffusion agent and/or a light-absorbing colorant may be mixed into a medium constituting the screen.
Inventors
- 👤 Masao Inoue
- 👤 Shingo Suzuki
- 👤 Hajime Gotoh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:42
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/72; G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/60; G03B21/62; G03B21/625
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
103 words
A rear projection screen comprising a projection surface upon which light from a projector impinges and a viewing surface, at least one of the screen surfaces being formed so as to serve as a lens so that the light which impinges on the projection surface produces on the viewing surface a multiplicity of bright stripe portions where the light is transmitted and a multiplicity of dark stripe portions where no light is transmitted, a plurality of elongated grooves formed along the dark stripe portions of the viewing surface and a corresponding plurality of thread-like members disposed in the elongated grooves as light-absorbing means.
Claim 2
Dependent Claim
103 words
A rear projection screen comprising a projection surface upon which light from a projector impinges and a viewing surface, at least one of the screen surfaces being formed so as to serve as a lens so that the light which impinges on the projection surface produces on the viewing surface a multiplicity of bright stripe portions where the light is transmitted and a multiplicity of dark stripe portions where no light is transmitted, a plurality of elongated grooves formed along the dark stripe portions of the viewing surface and a corresponding plurality of thread-like members disposed in the elongated grooves as light-absorbing means.
Claim 3
Dependent Claim
26 words
A rear projection screen according to claim 1, wherein said projection surface is provided with a lenticular lens means so as to serve as a lens.
Claim 4
Dependent Claim
26 words
A rear projection screen according to claim 1, wherein said viewing surface is provided with a lenticular lens means so as to serve as a lens.
Claim 5
Dependent Claim
28 words
A rear projection screen according to claim 3, wherein said lenticular lens means includes lenticules formed with total reflection surfaces provided on both sides of the elongated grooves.
Claim 6
Dependent Claim
15 words
A rear projection screen according to claim 4, wherein said total reflection surfaces are planar.
Claim 7
Dependent Claim
18 words
A rear projection screen according to claim 1, wherein a Fresnel lens is provided on said projection surface.
Claim 8
Dependent Claim
22 words
A rear projection screen according to claim 1, wherein both said projection surface and viewing surface are provided with lenticular lens means.
Claim 9
Dependent Claim
14 words
A rear projection screen according to claim 1, wherein said thread-like members are adhesive.
Claim 10
Dependent Claim
17 words
A rear projection screen according to claim 1, wherein the rear projection screen incorporates a diffusion agent.
Claim 11
Dependent Claim
18 words
A rear projection screen according to claim 1, wherein the rear projection screen incorporates a light absorbing colorant.
Claim 12
Dependent Claim
35 words
A rear projection screen according to claim 1, wherein said thread-like members are held under tension, and the surface of said screen in which the thread-like members are disposed is formed into a curved surface.
Claim 13
Dependent Claim
127 words
A rear projection screen comprising a projection surface upon which light from a projector impinges and a viewing surface, the viewing surface being provided with a lenticular lens so as to serve as a lens so that light impinging on the projection surface produces a multiplicity of brights stripe portions where the light is transmitted and a multiplicity of dark stripe portions where no light is transmitted, a plurality of grooves formed in the lenticular lens, each groove being formed with inclined total reflection surfaces on both sides, each total reflection surface being provided with a layer of a substance having a refractive index lower than that of a medium constituting said rear projection screen, and a thread-like member bonded in each groove as a light-absorbing means.
Claim 14
Dependent Claim
127 words
A rear projection screen comprising a projection surface upon which light from a projector impinges and a viewing surface, the viewing surface being provided with a lenticular lens so as to serve as a lens so that light impinging on the projection surface produces a multiplicity of brights stripe portions where the light is transmitted and a multiplicity of dark stripe portions where no light is transmitted, a plurality of grooves formed in the lenticular lens, each groove being formed with inclined total reflection surfaces on both sides, each total reflection surface being provided with a layer of a substance having a refractive index lower than that of a medium constituting said rear projection screen, and a thread-like member bonded in each groove as a light-absorbing means.
Claim 15
Dependent Claim
18 words
A rear projection screen according to claim 12, wherein a Fresnel lens is provided on said projection surface.
Claim 16
Dependent Claim
20 words
A rear projection screen according to claim 12 or claim 13, wherein the rear projection screen incorporates a diffusion agent.
Claim 17
Dependent Claim
19 words
A rear projection screen according to claim 12 or claim 13, wherein the rear projection screen incorporates a colorant.
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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) | 1988-06-24 | 1988-12-24 | 1989-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-24 | 1992-12-24 | 1993-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-24 | 1996-12-24 | 1997-06-25 | $7700.00 | Window Closed / Lapsed |