US4642736A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light diffuser
Assignee: Mitsubishi Chemical Corp
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Filing: 1985-04-17
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Granted: 1987-02-10
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Expires: 2005-04-17
Abstract
Abstract An edge-lighting type light diffuser is disclosed which has a plane of light incidence, a light transmitting means and a plane of light emission. The light transmitting means is composed of a laminate of a plurality of light-transmissible plates. This structure provides a light diffuser capable of uniform plane illumination usable for sign boards, large-sized display devices, display devices for various types of machinery, and liquid crystal devices.
Inventors
- 👤 Tokihiko Masuzawa
- 👤 Yoshitaka Kageyama
- 👤 Norizou Tomita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:27
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/0001; G02B6/0011; G02B6/0013; G02B6/0023; G02B6/003; F; F21; F21V; F21V7/00; G02B6/0033; G02B6/0035; G02B6/0038; G02B6/0045; G02B6/0046; G02B6/0048; G02B6/005; G02B6/0051; G02B6/0066; G02B6/007; G02B6/0071; G09; G09F; G09F13/00; G09F13/18; G09F2013/1804; G09F2013/1822; G09F2013/1827
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
171 words
An edge lighting type light diffuser comprising: (a) a plane of light incidence; (b) light transmitting means which, in use, receive light rays from said plane of light incidence; (c) a plane of light emission through which the light rays are emitted; and (d) means for reflecting the light rays transmitted through said light transmitting means, (e) said light transmitting means comprising a plurality of light-transmitting plates having planar surfaces superimposed on each other, each one of said plurality of light-transmitting plates having: (i) a first edge against which light is incident during use of the diffuser, said first edges collectively comprising said plane of light incidence, and (ii) a second edge normal to the surfaces of said light transmitting plates, said second edges being spaced from each other to form a staircase structure, each of said second edges being inclined relative to said plane of light incidence, and (f) said means for reflecting the light rays being located in linear contact with said second edges of said light transmitting plates.
Claim 2
Dependent Claim
171 words
An edge lighting type light diffuser comprising: (a) a plane of light incidence; (b) light transmitting means which, in use, receive light rays from said plane of light incidence; (c) a plane of light emission through which the light rays are emitted; and (d) means for reflecting the light rays transmitted through said light transmitting means, (e) said light transmitting means comprising a plurality of light-transmitting plates having planar surfaces superimposed on each other, each one of said plurality of light-transmitting plates having: (i) a first edge against which light is incident during use of the diffuser, said first edges collectively comprising said plane of light incidence, and (ii) a second edge normal to the surfaces of said light transmitting plates, said second edges being spaced from each other to form a staircase structure, each of said second edges being inclined relative to said plane of light incidence, and (f) said means for reflecting the light rays being located in linear contact with said second edges of said light transmitting plates.
Claim 3
Dependent Claim
39 words
A light diffuser as claimed in claim 1, wherein each one of said plurality of light-transmitting plates is inclined at an angle of more than 90° and less than 135° measured clockwise therefrom to said plane of light incidence.
Claim 4
Dependent Claim
20 words
A light diffuser as claimed in claim 1, wherein said plurality of light-transmitting plates are formed of a methacrylic resin.
Claim 5
Dependent Claim
20 words
A light diffuser as claimed in claim 1, wherein said means for reflecting the light rays comprises a metal-deposited film.
Claim 6
Dependent Claim
24 words
A light diffuser as claimed in claim 1, wherein said means for reflecting the light rays comprises a polyester film having a mirror surface.
Claim 7
Dependent Claim
20 words
A light diffuser as claimed in claim 1, wherein said means for reflecting the light rays has a smooth surface.
Claim 8
Dependent Claim
43 words
A light diffuser as claimed in claim 1 wherein said second edges of said plurality of light-transmitting plates are inclined from said plane of light incidence at a first predetermined angle and from said plane of light emission at a second predetermined angle.
Claim 9
Dependent Claim
17 words
A light diffuser as claimed in claim 7, wherein said first predetermined angle is less than 135°.
Claim 10
Dependent Claim
17 words
A light diffuser as claimed in claim 7, wherein said first predetermined angle is less than 45°.
Claim 11
Dependent Claim
36 words
A light diffuser as claimed in claim 1, and further comprising a light diffusion means for diffusing the reflected light rays, said light diffusion means being provided opposite to said means for reflecting the light rays.
Claim 12
Dependent Claim
28 words
A light diffuser as claimed in claim 10, wherein said light diffusing means has a plurality of small protrusions on a surface thereof facing said light transmitting means.
Claim 13
Dependent Claim
21 words
A light diffuser as claimed in claim 10, wherein said light diffusing means is formed of a white opaque light-transmitting material.
Claim 14
Dependent Claim
24 words
A light diffuser as claimed in claim 12, wherein said white opaque light-transmitting material is an acrylic resin film containing a light diffusing agent.
Claim 15
Dependent Claim
24 words
A light diffuser as claimed in claim 12, wherein said white opaque light-transmitting material is an acrylic polymer film containing a light diffusing agent.
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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) | 1990-02-09 | 1990-08-11 | 1991-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-09 | 1994-08-11 | 1995-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-09 | 1998-08-11 | 1999-02-10 | $7700.00 | Window Closed / Lapsed |