Patent EP0736796A1 successfully refreshed from Google Patents.
EP0736796A1
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Rear-projection screen
Assignee: Kuraray Co Ltd
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Filing: 1996-04-03
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Granted: —
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Expires: 2016-04-03
Abstract
Abstract A rear-projection screen having at least a Fresnel lens (1) and a light-diffusing member (4), and is characterized by having vertical-direction light diffusion properties greater at its upper and lower end portions than at its middle portion. For example, the light-diffusing member (4) contains light-diffusing fine particles (7) and has a vertical lenticular lens (3) that diffuses light in the vertical direction, provided on the light-incident surface of the Fresnel lens (1). This decreases the rainbows caused by misdirected light and also improves the brightness at the border, without causing a lowering of peak gain.
Inventors
- 👤 Osamu c/o Kuraray Co. Ltd. Yoshimura
- 👤 Ichiro c/o Kuraray Co. Ltd. Matuszaki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 02:24
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/60; G03B21/62; G03B21/625
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
34 words
A rear-projection screen comprising a Fresnel lens (1) and a light-diffusing member (4): wherein said screen has vertical-direction light diffusion properties greater at its upper and lower end portions than at its middle portion.
Claim 2
Dependent Claim
67 words
The rear-projection screen according to claim 1, wherein the middle portion of said screen (1,4) has an extent which is within 15% in the height direction from the mechanical center of the Fresnel lens (1) of the rear-projection screen, and the upper and lower end portions each have an extent which is 70% outward in the height direction from the mechanical center of the Fresnel lens thereof.
Claim 3
Dependent Claim
60 words
The rear-projection screen according to claim 1 or 2, wherein light-diffusing fine particles as a means for diffusing light in the vertical direction are incorporated in said light-diffusing member (4), and the concentration of the light-diffusing fine particles in said light-diffusing member (4) is higher at the upper and lower end portions than at the middle portion of the screen.
Claim 4
Dependent Claim
61 words
The rear-projection screen according to any one of claims 1 to 3, wherein a vertical lenticular lens (10) that diffuses light in the vertical direction is provided as a means for diffusing light in the vertical direction, and the vertical lenticular lens (10) has vertical-direction light diffusion properties greater at its upper and lower end portions than at its middle portion.
Claim 5
Dependent Claim
23 words
The rear-projection screen according to claim 4, wherein said vertical lenticular lens (10) is formed on the light-incident surface of the Fresnel lens.
Claim 6
Dependent Claim
46 words
The rear-projection screen according to claim 4, wherein said vertical lenticular lens (10) has a constant height of lens hills , and has a pitch of lens hills which is smaller at the upper and lower end portions than at the middle portion of the screen.
Claim 7
Dependent Claim
46 words
The rear-projection screen according to claim 4, wherein said vertical lenticular lens (10) has a constant pitch of lens hills , and has a height of lens hills which is greater at the upper and lower end portions than at the middle portion of the screen.
Claim 8
Dependent Claim
62 words
The rear-projection screen according to claim 4, wherein said vertical lenticular lens (10) has a pitch of lens hills which is smaller at the upper and lower end portions than at the middle portion of the screen, and has a height of lens hills which is greater at the upper and lower end portions than at the middle portion of the screen.
References Cited (Backward Citations)
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