Patent US2441715A successfully refreshed from Google Patents.
EP0333333A1
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EP
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Display device
Assignee: EMI Group Ltd
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Filing: 1989-02-22
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Granted: —
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Expires: 2009-02-22
Abstract
Abstract A display device includes equipment for projecting light, onto a surface (5). The equipment includes a beam-splitter (2, 30) for effecting partial reflection and partial transmittance of an incident beam. On one side of the beam-splitter (2, 30) are a light source (10) for directing light onto the beam-splitter and a mirror (4) for directing back towards the beam-splitter (2, 30) light reflected therefrom. On the other side of the beam-splitter (2, 30) is a louvre (3, 20) for permitting passage therethrough of light of incident angle relative to a normal to the beam-splitter (3, 20) within a predetermined restriction range.
Inventors
- 👤 Graham Leslie Wright
- 👤 Mark Dempster
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 10:09
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/74; H04N5/7408; G; G02; G02B; G02B17/00; G02B17/02; G03; G03B; G03B21/00; G03B21/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
98 words
Equipment for projecting light onto a surface, the equipment comprising: beam-splitting means for effecting partial reflection and partial transmittance of an incident beam; a light source located on one side of the beam-splitting means for directing light onto the beam-splitting means; mirror means on said one side of the beam-splitting means for directing back towards the beam-splitting means light reflected from the beam-splitting means; and louvre means located on the other side of the beam-splitting means for permitting passage therethrough of light in a predetermined restricted range of incident angles relative to a normal to the beam-splitting means.
Claim 2
Dependent Claim
98 words
Equipment for projecting light onto a surface, the equipment comprising: beam-splitting means for effecting partial reflection and partial transmittance of an incident beam; a light source located on one side of the beam-splitting means for directing light onto the beam-splitting means; mirror means on said one side of the beam-splitting means for directing back towards the beam-splitting means light reflected from the beam-splitting means; and louvre means located on the other side of the beam-splitting means for permitting passage therethrough of light in a predetermined restricted range of incident angles relative to a normal to the beam-splitting means.
Claim 3
Dependent Claim
20 words
Equipment according to Claim 1 wherein the light source includes a display panel for producing an image to be projected.
Claim 4
Dependent Claim
30 words
Equipment according to Claims 1 or 2 wherein said predetermined restricted range of incident angles relative to a normal to the beam-splitting means varies with position along the louvre means.
Claim 5
Dependent Claim
59 words
Equipment according to Claim 3, the louvre means comprising a substrate having a plurality of passageways arranged in side-by-side relation for allowing transmission of light of an incident angle relative to an axis of a passageway within a predetermined range wherein two or more adjacent passageways have a transmission direction at an angle of deviation from a parallel relationship.
Claim 6
Dependent Claim
21 words
Equipment according to Claims 1 or 2 further comprising a Fresnel lens arrangement intermediate the beam-splitting means and the louvre means.
Claim 7
Dependent Claim
22 words
Equipment according to any one of the preceding claims wherein the beam-splitting means comprises a substrate having alternating reflective and transparent strips.
Claim 8
Dependent Claim
31 words
Equipment according to any one of the preceding claims wherein an anti-reflection coating is provided on a surface of the beam-splitting means on said other side of the beam splitting means.
References Cited (Backward Citations)
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