Patent US3894857A successfully refreshed from Google Patents.
US3894857A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for exchanging alkali ions for thallium ions in a glass fiber
Assignee: Nippon Selfoc Co Ltd
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Filing: 1974-01-23
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Granted: 1975-07-15
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Expires: 1994-01-23
Abstract
Abstract A novel laser comprises a fiber-like light transmission medium having a gradient in the refractive index which is greatest at its axis and gradually decreases toward the surface and which includes activable ions substantially uniformly distributed throughout.
Inventors
- 👤 Teiji Uchida
- 👤 Shogo Yoshikawa
- 👤 Ken Koizumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:29
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/29; H04B10/291; C; C03; C03C; C03C21/00; C03C21/001; H01; H01S; H01S3/00; H01S3/05; H01S3/06; H01S3/063; H01S3/067; H01S3/06708; H01S3/06716; H01S3/14; H01S3/16; H01S3/17; H04B10/2912
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
93 words
A PROCESS FOR FABRICATING A GLASS FIBER LASER ELEMENT IN WHICH THE REFRACTIVE INDEX INCREASES FROM THE SURFACE TO THE LONGITUDINAL AXIS THEREOF, SIAID METHOD COMPRISING THE STEPS OF PROVIDING A GLASS BODY INCLUDING IONS OF RARE EARTH METAL AND IONS OF THALLIUM UNIFORMLY DISTRIBUTED THEREIN, AND IMMERSING SAID GLASS BODY INTO A HEATED MOLTEN SALT OF AN ALKALI METAL TO ALLOW IONS OF SAID ALKALI METAL TO DIFFUSE INTO SAID GLASS BODY, WHEREBY SAID THALLIUM IONS ARE EXCHANGED BY IONS OF SAID ALKALI METAL AND THE CONCENTRATION OF SAID THALLIUM IONS DECREASES
Claim 2
Dependent Claim
93 words
A PROCESS FOR FABRICATING A GLASS FIBER LASER ELEMENT IN WHICH THE REFRACTIVE INDEX INCREASES FROM THE SURFACE TO THE LONGITUDINAL AXIS THEREOF, SIAID METHOD COMPRISING THE STEPS OF PROVIDING A GLASS BODY INCLUDING IONS OF RARE EARTH METAL AND IONS OF THALLIUM UNIFORMLY DISTRIBUTED THEREIN, AND IMMERSING SAID GLASS BODY INTO A HEATED MOLTEN SALT OF AN ALKALI METAL TO ALLOW IONS OF SAID ALKALI METAL TO DIFFUSE INTO SAID GLASS BODY, WHEREBY SAID THALLIUM IONS ARE EXCHANGED BY IONS OF SAID ALKALI METAL AND THE CONCENTRATION OF SAID THALLIUM IONS DECREASES
Claim 3
Dependent Claim
45 words
The method of claim 1, in which said glass body is formed by fusing a pipe-shaped glass body having an outer diameter and an inner diameter and a rod-shaped glass body having a diameter substantially equal to said inner diameter of said pipe-shaped glass body.
Claim 4
Dependent Claim
47 words
The method of claim 1, in which said glass body further includes, prior to said immersion step replaceable sodium ions distributed uniformly therein, said ions of said alkali metal from said heated molten salt being exchanged for some of said replaceable sodium ions, during said immersion step.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-14 | 1979-01-13 | 1979-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-14 | 1983-01-13 | 1983-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-14 | 1987-01-13 | 1987-07-15 | $7700.00 | Window Closed / Lapsed |