EP0469313A2
Expired / Lapsed
EP
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Transmission-type screen for a projection television device
Assignee: Panasonic Holdings Corp
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Filing: 1991-07-02
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Granted: —
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Expires: 2011-07-02
Abstract
Abstract A transmission-type video projection television system employs a transmission-type screen for displaying an image projected from a rear projector for visual observation by an observer in front of the screen. The transmission-type screen has Fresnel and lenticular lenses, one of which has an electrically conductlve layer or a metal member on its surface to prevent the lens from being electrostatically charged, so that dust or dirt particles will not be attracted to the screen. <IMAGE>
Inventors
- 👤 Katsuaki Mitani
- 👤 Toshiaki Matsumura
- 👤 Noboru Yasumatsuya
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 12:32
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/60; G03B21/62; G03B21/625
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
36 words
A transmission-type screen comprising: a lens for transmitting rays of light therethrough; and an electrically conductive layer or a metal member mounted on a surface of said lens for preventing said surface from being electrostatically charged.
Claim 2
Dependent Claim
36 words
A transmission-type screen comprising: a lens for transmitting rays of light therethrough; and an electrically conductive layer or a metal member mounted on a surface of said lens for preventing said surface from being electrostatically charged.
Claim 3
Dependent Claim
69 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said lenticular lens having a plurality of black stripes on an exit-side surface thereof for absorbing and blocking rays of light, said black stripes being made of an electrically conductive material having a surface resistance of 1 x 10 9 Q or less.
Claim 4
Dependent Claim
75 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said lenticular lens having a plurality of parallel spaced grooves defined in an entrance-side surface thereof, and a plurality of electrically condutive layers disposed in said grooves, respectively, said electrically conductive layers being made of a material having a surface resistance of 1 x 10 9 Q or less.
Claim 5
Dependent Claim
74 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said Fresnel lens having a plurality of axial steps on an exit-side surface thereof, and a plurality of electrically conductive layers attached to said axial steps, respectively, said electrically conductive layers being made of a material having a surface resistance of 1 x 10 9 Q or less.
Claim 6
Dependent Claim
84 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said Fresnel lens having a plurality of parallel spaced grooves defined in an entrance-side surface thereof for increasing a vertical field of view, and a plurality of electrically conductive layers or metal wires disposed respectively in said grooves, said electrically conductive layers being made of a material having a surface resistance of 1 X 109 Q or less.
Claim 7
Dependent Claim
64 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said Fresnel lens having electrically conductive layers disposed in a grid pattern on an entrance-side surface thereof, said electrically conductive layers being made of a material having a surface resistance of 1 x 10 9 f2 or less.
Claim 8
Dependent Claim
42 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said Fresnel lens having a grid-like meshwork of metal wires disposed on an entrance-side surface thereof.
Claim 9
Dependent Claim
80 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said lenticular lens having a plurality of parallel spaced black stripes disposed on an exit-side surface thereof and a plurality of parallel spaced grooves defined in an entrance-side surface thereof, said lenticular lens further including a plurality of metal wires disposed respectively in said black stripes or said grooves and having partly exposed surfaces.
Claim 10
Dependent Claim
58 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said lenticular lens having a plurality of black, parallel spaced electrically conductive layers disposed on an exit-side surface thereof, and a plurality of black stripes disposed respectively on said electrically conductive layers.
Claim 11
Dependent Claim
71 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and an array of parallel optical fibers which are positioned closely parallel to each other, said optical fibers being bonded by adhesive layers each comprising a mixture of an adhesive and an electrically conductive material which is added at a proportion such that said mixture has a surface resistance of 1 x 10 9 f2 or less.
Claim 12
Dependent Claim
71 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and an array of parallel optical fibers which are positioned closely parallel to each other, said optical fibers being bonded by adhesive layers, and including electrically conductive layers disposed respectively on said adhesive layers, each of said electrically conductive layers being made of a material having a surface resistance of 1 x 10 9 Q or less.
Claim 13
Dependent Claim
83 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said lenticular lens having a plurality of parallel spaced black stripes disposed on an exit-side surface thereof and an electrically conductive layer interconnecting said black stripes and extending along outer peripheral edges of said lenticular lens, said electrically conductive layer being made of a material having a surface resistance of 1 x 10 9 Q or less.
Claim 14
Dependent Claim
79 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said lenticular lens having a plurality of parallel spaced black stripes disposed on an exit-side surface thereof and an electrically conductive layer interconnecting said black stripes and disposed over said exit-side surface, said electrically conductive layer being made of a material having a surface resistance of 1 x 10 9 Q or less.
Claim 15
Dependent Claim
83 words
A transmission-type screen according to claim 1, wherein said lens comprises a Fresnel lens and a lenticular lens which are positioned closely parallel to each other, said lenticular lens having a plurality of parallel spaced black stripes disposed on an exit-side surface thereof, further comprising a frame of an electrically conductive material or a metal surrounding outer peripheral edges of said Fresnel lens and said lenticular lens, said electrically conductive material having a surface resistance of 1 x 10 9 Q or less.
Claim 16
Dependent Claim
26 words
A transmission-type screen according to claim 12, 13, or 14, further comprising a ground wire by which said electrically conductive layer or said frame is grounded.
Claim 17
Dependent Claim
79 words
A transmission-type screen according to claim 1, wherein said electrically conductive layer is made of a mixture of one of a printing paste, a paint, and an adhesive and carbon whose proportion is selected such that said mixture has a surface resistance of 1 x 10 9 Q or less, or a mixture of carbon and another electrically conductive material at proportions selected such that said mixture has a surface resistance of 1 x 10 9 Q or less.
Claim 18
Dependent Claim
51 words
A video projection television system comprising: a screen comprising a lens for transmitting rays of light therethrough, and an electrically conductive layer or a metal member mounted on a surface of said lens for preventing said surface from being electrostatically charged; and a projector for projecting an image onto said screen.
Claim 19
Dependent Claim
51 words
A video projection television system comprising: a screen comprising a lens for transmitting rays of light therethrough, and an electrically conductive layer or a metal member mounted on a surface of said lens for preventing said surface from being electrostatically charged; and a projector for projecting an image onto said screen.
References Cited (Backward Citations)
No citation records indexed.
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