Patent US1575125A successfully refreshed from Google Patents.
US3740113A
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Light guide
Assignee: Imperial Chemical Industries Ltd
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Filing: 1970-02-16
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Granted: 1973-06-19
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Expires: 1990-02-16
Abstract
Abstract A flexible light guide comprises a flexible tube of a transparent thermoplastic containing a transparent liquid having a higher refractive index than the thermoplastic. The tubing may be of a polymer or copolymer of 4-methyl pentene-1 or any clear plastic tubing.
Inventors
- 👤 M Cass
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:44
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/02; G02B6/032
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
27 words
The light guide of claim 1 wherein the plug of transparent material is selected from an acrylic polymer, glass, and the same material as the flexible tube.
Claim 2
Dependent Claim
25 words
The light guide of claim 1 wherein the fluid in the tube is a liquid which is coloured with a dyestuff soluble in the liquid.
Claim 3
Dependent Claim
24 words
The light guide of claim 1 wherein the tube is formed of clear polyvinyl chloride and the fluid is selected from nitrobenzene and camphor.
Claim 4
Dependent Claim
26 words
The light guide of claim 1 wherein the tube is formed of a 4-methyl pentene-1 polymer and the fluid is selected from camphor and benzyl alchol.
Claim 5
Dependent Claim
18 words
The light guide of claim 5 wherein the 4-methyl pentene-1 polymer is a copolymer with a linear olefine.
Claim 6
Dependent Claim
24 words
The light guide of claim 6 wherein the 4-methyl pentene-1 polymer is a copolymer with a linear olefin selected from hexene-1, octene-1 or decene-1.
Claim 7
Dependent Claim
20 words
The light guide of claim 6 wherein the copolymer contains up to 10 percent by weight of the linear comonomer.
Claim 8
Dependent Claim
21 words
The light guide of claim 8 wherein the copolymer contains from 4 to 6 percent by weight of the linear comonomer.
References Cited (Backward Citations)
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Cited
US3030852A
Cited
US3363174A
Cited
GB1037498A
Cited
US3434776A
Cited
US3510195A
Cited
US3492493A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-18 | 1976-12-18 | 1977-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-18 | 1980-12-18 | 1981-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-18 | 1984-12-18 | 1985-06-19 | $7700.00 | Window Closed / Lapsed |