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US4709988A Expired / Lapsed US ⏱️ 0.0 years remaining

Directional light-shield board

Assignee: Nissan Motor Co Ltd
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Filing: 1985-11-04
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Granted: 1987-12-01
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Expires: 2005-11-04
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Abstract

Abstract Disclosed is a light-shield board for placement in front of a visual display device such as a cathode-ray tube in a television set or an information system. The light-shield board comprises a transparent substrate and an opaque film which is bonded to the substrate and is formed with a number of substantially uniformly distributed light-transmitting apertures, which may be rectangular apertures arranged in a checkered pattern. So, the opaque film comprises wall-like parts respectively partitioning the apertures. The apertures are bored obliquely such that at least a selected portion of the wall-like parts of the film are unidirectionally inclined from a plane normal to the film. Besides the function of restricting the angle of incidence of extraneous light on the display screen, this light-shield board serves the purpose of controlling the angles of diffusion of light from the display screen and hence enabling to sight the display screen from limited directions only. For example, by applying this light-shield board to a car television set in the instrument panel it is possible to disenable the driver to sight the television screen while a passenger in the front seat next to the driver can sight the screen.

Inventors

  • 👤 Yasuaki Kai
  • 👤 Takatoshi Sagawa
  • 👤 Hiroshi Tabata

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 17:15
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/86; H01J29/89; G; G02; G02B; G02B5/00; H01J2229/00; H01J2229/89; H01J2229/8905; H01J2229/8909

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 140 words
A directional light-shield board for placement in front of a visual display device, the light-shield board comprising: a transparent substrate; and an opaque film which is bonded to a major surface of said substrate and is formed with a number of substantially uniformly distributed light-transmitting apertures such that said opaque film comprises a number of wall-like parts respectively partitioning said apertures, said apertures having a substantially rectangular shape and arranged in a checkered pattern, said apertures being bored obliquely such that at least a first pair of parallel wall-like parts of said opaque film are substantially unidirectionally inclined from a plane normal to said surface of said substrate and such that an apparent area of each of said apertures become maximum when the light-shield board is viewed from the direction of the inclination of said wall-like parts of said film.
Claim 2
Dependent Claim 140 words
A directional light-shield board for placement in front of a visual display device, the light-shield board comprising: a transparent substrate; and an opaque film which is bonded to a major surface of said substrate and is formed with a number of substantially uniformly distributed light-transmitting apertures such that said opaque film comprises a number of wall-like parts respectively partitioning said apertures, said apertures having a substantially rectangular shape and arranged in a checkered pattern, said apertures being bored obliquely such that at least a first pair of parallel wall-like parts of said opaque film are substantially unidirectionally inclined from a plane normal to said surface of said substrate and such that an apparent area of each of said apertures become maximum when the light-shield board is viewed from the direction of the inclination of said wall-like parts of said film.
Claim 3
Dependent Claim 16 words
A light-shield board according to claim 1, wherein said checkered pattern is a staggered checkered pattern.
Claim 4
Dependent Claim 37 words
A light-shield board according to claim 1, wherein each of the rectangular light-transmitting apertures further comprises a second pair of parallel wall-like parts of said film, said second pair of wall-like parts being normal to said plane.
Claim 5
Dependent Claim 31 words
A light-shield board according to claim 3, wherein said opaque film formed with said apertures is produced by a photolithographic method using a photosensitive resin as the material of said film.
Claim 6
Dependent Claim 28 words
A light-shield board according to claim 1, further comprising a light-transmitting plate which is arranged opposite to said transparent substrate and to which said opaque film is bonded.
Claim 7
Dependent Claim 19 words
A light-shield board according to claim 5, wherein said light-transmitting plate is lower in transmittance than said transparent substrate.
Claim 8
Dependent Claim 20 words
A light-shield board according to claim 5, wherein an outer surface of said light-transmitting plate is made a rough surface.
Claim 9
Dependent Claim 28 words
A light-shield board according to claim 7, wherein surface roughness of said rough surface is not greater than about 0.25 microns in terms of center line average height.
Claim 10
Dependent Claim 31 words
A light-shield board according to claim 1, wherein said opaque film formed with said apertures is produced by a photolithographic method using a photosensitive resin as the material of said film.
Claim 11
Dependent Claim 15 words
A light-shield board according to claim 9, wherein said photosensitive resin contains a matting agent.
Claim 12
Dependent Claim 192 words
A light-shield board having a transparent substrate and an opaque film comprising at least a first pair of parallel wall-like parts which are substantially unidirectionally inclined from a plane normal to a surface of said substrate and having at least a second pair of parallel wall-like parts which are normal to the plane of the substrate, prepared by a process consisting essentially of the steps of: placing a mask sheet on a first transparent glass plate; overlaying a first transparent polyester film onto said mask sheet; locating a spacer on said first transparent glass plate so as to form a border around said mask sheet and said first transparent polyester film; depositing a photosensitive liquid resin onto said first transparent polyester film; overlaying a second transparent polyester film onto said photosensitive liquid resin; placing a second transparent glass plate on said second transparent polyester film so as to provide a curing assembly; directing rays of light through said curing assembly to cure selected portions of said photosensitive liquid resin; treating said selected cured portions of said photosensitive resin to produce a suitable aperture film; and mounting said aperture film onto said substrate.
Claim 13
Dependent Claim 192 words
A light-shield board having a transparent substrate and an opaque film comprising at least a first pair of parallel wall-like parts which are substantially unidirectionally inclined from a plane normal to a surface of said substrate and having at least a second pair of parallel wall-like parts which are normal to the plane of the substrate, prepared by a process consisting essentially of the steps of: placing a mask sheet on a first transparent glass plate; overlaying a first transparent polyester film onto said mask sheet; locating a spacer on said first transparent glass plate so as to form a border around said mask sheet and said first transparent polyester film; depositing a photosensitive liquid resin onto said first transparent polyester film; overlaying a second transparent polyester film onto said photosensitive liquid resin; placing a second transparent glass plate on said second transparent polyester film so as to provide a curing assembly; directing rays of light through said curing assembly to cure selected portions of said photosensitive liquid resin; treating said selected cured portions of said photosensitive resin to produce a suitable aperture film; and mounting said aperture film onto said substrate.

References Cited (Backward Citations)

US3511563A Cited
US3996458A Cited
JPS57189439A Cited
US4506953A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-11-30 1991-06-01 1991-12-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-11-30 1995-06-01 1995-12-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-11-30 1999-06-01 1999-12-01 $7700.00 Window Closed / Lapsed

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