US4199335A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of optical fibers for transmission of communication
Assignee: Schott AG
•
Filing: 1978-09-12
•
Granted: 1980-04-22
•
Expires: 1998-09-12
Abstract
Abstract In a process for the production of communication fibers having transmission losses of less than 10 db/km. and a pulse dispersion of less than 4 ns/km., both measured at 860 nm, by the internal cladding method, wherein multiple-component glasses are deposited in layers in the glassy state in the interior of a glass tube; the tube thus clad inside, is collapsed to a rod; and the rod is drawn into a fiber, the core diameter of which has an eccentricity of less than 2%, an improvement is provided wherein a precollapsing step is executed prior to the final collapsing process, the precollapsing step occurring during the internal cladding step. The temperature of the cladding step is greater than 1850° C. and above the softening point of the glass tube.
Inventors
- 👤 Georg Gliemeroth
- 👤 Lothar Meckel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:30
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/018; C03B37/01861; Y; Y02; Y02P; Y02P40/00; Y02P40/50; Y02P40/57
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
167 words
In a process for the production of communication fibers having transmission losses of less than 10 db/km and a pulse dispersion of less than 4 ns/km, both measured at 860 nm by the internal cladding method, wherein multiple-component glasses are deposited in layers in the glassy state in the interior of a glass tube; the tube thus clad inside, is collapsed to a rod; and the rod is drawn into a fiber, the core diameter of which has an eccentricity of lesss than 2%, the improvement wherein a precollapsing step is executed prior to the final collapsing process, the precollapsing step occurring during the internal cladding step, wherein the glass tube is precollapsed during the internal cladding step to such an extent that the ratio R i /r i is larger than 1.7, wherein R i is the inner tube radius prior to the cladding step and r i is the inner tube radius after completion of the cladding step and prior to the final collapsing step.
Claim 2
Dependent Claim
167 words
In a process for the production of communication fibers having transmission losses of less than 10 db/km and a pulse dispersion of less than 4 ns/km, both measured at 860 nm by the internal cladding method, wherein multiple-component glasses are deposited in layers in the glassy state in the interior of a glass tube; the tube thus clad inside, is collapsed to a rod; and the rod is drawn into a fiber, the core diameter of which has an eccentricity of lesss than 2%, the improvement wherein a precollapsing step is executed prior to the final collapsing process, the precollapsing step occurring during the internal cladding step, wherein the glass tube is precollapsed during the internal cladding step to such an extent that the ratio R i /r i is larger than 1.7, wherein R i is the inner tube radius prior to the cladding step and r i is the inner tube radius after completion of the cladding step and prior to the final collapsing step.
Claim 3
Dependent Claim
24 words
A process of claim 1, wherein the internal temperature of the tube during the entire internal cladding process is maintained at above 1850° C.
Claim 4
Dependent Claim
133 words
In a process for the production of communication fibers having transmission losses of less than 10 db/km and a pulse dispersion of less than 4 ns/km, both measured at 860 nm by the internal cladding method, wherein multiple-component glasses are deposited in layers in the glassy state in the interior of a glass tube; the tube thus clad inside, is collapsed to a rod; and the rod is drawn into a fiber, the core diameter of which has an eccentricity of less than 2%, the improvement wherein a precollapsing step is executed prior to the final collapsing process, the precollapsing step occurring during the internal cladding step, wherein the glass tube is made of silicate glass and the internal cladding is conducted at a temperature lying above the softening temperature of silicate glass.
Claim 5
Dependent Claim
133 words
In a process for the production of communication fibers having transmission losses of less than 10 db/km and a pulse dispersion of less than 4 ns/km, both measured at 860 nm by the internal cladding method, wherein multiple-component glasses are deposited in layers in the glassy state in the interior of a glass tube; the tube thus clad inside, is collapsed to a rod; and the rod is drawn into a fiber, the core diameter of which has an eccentricity of less than 2%, the improvement wherein a precollapsing step is executed prior to the final collapsing process, the precollapsing step occurring during the internal cladding step, wherein the glass tube is made of silicate glass and the internal cladding is conducted at a temperature lying above the softening temperature of silicate glass.
Claim 6
Dependent Claim
45 words
A process of claim 1, wherein the glass tube has a wall thickness such that R o /R i is larger than 1.15, wherein R o is the outer tube radius and R i is the inner tube radius, both prior to the cladding step.
Claim 7
Dependent Claim
14 words
A process of claim 1, wherin the glass tube is made of silicate glass.
Claim 8
Dependent Claim
22 words
A process of claim 5, wherin the internal cladding is conducted at a temperature lying above the softening temperature of silicate glass.
Claim 9
Dependent Claim
45 words
In a process which comprises coating at least one layer of glass onto the inner surface of a heated silicate glass tube by chemical vapor deposition, the improvement wherein the temperature of the tube is about 1850°-2150° C. during the deposition of the glass layers.
Claim 10
Dependent Claim
45 words
In a process which comprises coating at least one layer of glass onto the inner surface of a heated silicate glass tube by chemical vapor deposition, the improvement wherein the temperature of the tube is about 1850°-2150° C. during the deposition of the glass layers.
Claim 11
Dependent Claim
33 words
The process of claim 7, wherein the composition of the sequential layers varies stepwise so that the refractive index profile of the layer is parabolic increasing inwardly towards the center of the tube.
Claim 12
Dependent Claim
27 words
The process of claim 8, which further comprises depositing at least one light-insulating layer of borosilicate glass on the tube prior to deposition of the light-conducting layers.
Claim 13
Dependent Claim
21 words
The process of claim 9, which further comprises collapsing the tube and then drawing it out to produce an optical fiber.
Claim 14
Dependent Claim
16 words
The process of claim 10, wherein the tube temperature during the cladding step is 1950°-2050° C.
Claim 15
Dependent Claim
10 words
The optical fiber produced by the process of claim 1.
Claim 16
Dependent Claim
10 words
The optical fiber produced by the process of claim 10.
Claim 17
Dependent Claim
143 words
In a process for making optical fibers which comprises rotating a silicate glass tube clamped to a synchronous lathe at 50-200 r.p.m.; heating the tube by means of an exterior burner of width 1--8 cm, travelling along the longitudinal axis of the tube at 0.15--3 m/min; passing a gas of O 2 through the tube at 100-2000 ml/min, said gas consisting essentially of carrier gas O 2 and entrained gases; and sequentially entraining in the carrier gas a mixture of predetermined composition of vaporized metallic compounds which when in the heated tube will be decomposed to a mixture of the corresponding metallic oxides which oxides will deposit on the inner surface of the tube to form a glass layer having a predetermined refractive index; the improvement wherein the temperature of the heated tube is 1850°-2150° C. during the deposition of the glass layers.
Claim 18
Dependent Claim
143 words
In a process for making optical fibers which comprises rotating a silicate glass tube clamped to a synchronous lathe at 50-200 r.p.m.; heating the tube by means of an exterior burner of width 1--8 cm, travelling along the longitudinal axis of the tube at 0.15--3 m/min; passing a gas of O 2 through the tube at 100-2000 ml/min, said gas consisting essentially of carrier gas O 2 and entrained gases; and sequentially entraining in the carrier gas a mixture of predetermined composition of vaporized metallic compounds which when in the heated tube will be decomposed to a mixture of the corresponding metallic oxides which oxides will deposit on the inner surface of the tube to form a glass layer having a predetermined refractive index; the improvement wherein the temperature of the heated tube is 1850°-2150° C. during the deposition of the glass layers.
Claim 19
Dependent Claim
33 words
The process of claim 2, wherein the temperature of the tube during the entire internal cladding process is maintained at a value which is at most 160° C. lower than the collapsing temperature.
References Cited (Backward Citations)
US4045198A
Cited
DE2741854A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-04-22 | 1983-10-22 | 1984-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-22 | 1987-10-22 | 1988-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-22 | 1991-10-22 | 1992-04-22 | $7700.00 | Window Closed / Lapsed |