Patent US4681244A successfully refreshed from Google Patents.
Patent US4567123A successfully refreshed from Google Patents.
US4567123A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diffusing plate
Assignee: Canon Inc
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Filing: 1985-01-25
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Granted: 1986-01-28
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Expires: 2005-01-25
Abstract
Abstract A diffusing plate having a smooth rough surface is obtained by recording on a photosensitive material the image of a mask having a regular fine pattern thereon, treating the photosensitive material to thereby obtain a photosensitive material having smooth roughness, transferring the smooth roughness of the treated photosensitive material to a metal mold, and embossing plastics on the metal mold.
Inventors
- 👤 Keiji Ohtaka
- 👤 Takashi Suzuki
- 👤 Kiyoshi Iizuka
- 👤 Hidemasa Mizutani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:11
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/0005; G03F7/001; G03B; G03B13/00; G03B13/18; G03B13/24; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
81 words
A method of making a diffusing plate having continuous roughness, said method comprising the steps of: exposing a photosensitive material to image light of a mask having a regular fine pattern; treating said photosensitive material to form regular, continuous roughness on the surface thereof; forming a mold having said regular, continuous roughness on the surface thereof by coating said regular, continuous roughness formed on the surface of said photosensitive material with metal; and embossing an optical material on said metal mold.
Claim 2
Independent Claim
81 words
A method of making a diffusing plate having continuous roughness, said method comprising the steps of: exposing a photosensitive material to image light of a mask having a regular fine pattern; treating said photosensitive material to form regular, continuous roughness on the surface thereof; forming a mold having said regular, continuous roughness on the surface thereof by coating said regular, continuous roughness formed on the surface of said photosensitive material with metal; and embossing an optical material on said metal mold.
Claim 3
Dependent Claim
24 words
A method according to claim 1, wherein the pitch of the regular fine pattern of said mask is about 10 to about 25 μm.
Claim 4
Dependent Claim
36 words
A method according to claim 1, wherein said mask has a rectangular transmission factor distribution and is disposed at a distance of several μm to several tens of μm from the surface of said photosensitive surface.
References Cited (Backward Citations)
US2399799A
Cited
US3277541A
Cited
JPS5483846A
Cited
JPS5590931A
Cited
US4523807A
Cited
US4430401A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-01-27 | 1989-07-29 | 1990-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-27 | 1993-07-29 | 1994-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-27 | 1997-07-29 | 1998-01-28 | $7700.00 | Window Closed / Lapsed |