# US 5,710,852 A · Optical waveguide for fiber-optic amplifiers for the wavelength region around 1550 nm

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,710,852 A
- Document ID: US5710852A
- Status: Granted
- Kind: A
- Application number: 08/462,702
- Filed: 1995-06-05
- Granted: 1998-01-20
- Earliest claimed: 1994-06-10
- Assignees: Alcatel
- Inventors: Dieter Weber
- Web page: https://patentgrep.com/patent/US5710852A

## CPC

- H01S 3/06708: {Constructional details of the fibre, e.g. compositions, cross-section, shape or tapering (optical fibres as passive waveguides G02B6/02)}
- C03B 37/01807: {Reactant delivery systems, e.g. reactant deposition burners}
- C23C 16/30: Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
- C03B 2201/10: doped with boron (C03B2201/14 takes precedence)
- C03B 2201/12: doped with fluorine (C03B2201/14 takes precedence)
- C03B 2201/28: doped with phosphorus
- C03B 2201/31: doped with germanium
- C03B 2201/34: doped with rare earth metals, i.e. with Sc, Y or lanthanides, e.g. for laser-amplifiers
- C03B 2201/36: doped with rare earth metals and aluminium, e.g. Er-Al co-doped
- H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- C03B: MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04)

## Abstract

An optical waveguide for fiber-optic amplifiers is disclosed where the Progression of the fluorescence band of optical waveguides that are doped with erbium and aluminum can be additionally flattened if the core contains fluorine, e.g., in the form of ErF.sub.3 and AIF.sub.3, as an additional doping agent.

## Claims

### Claim 1

An improved optical waveguide having silicon dioxide as the base material, the improved optical waveguide comprising:
A) a core comprising:
1) at least one doping agent to increase the refractive index of the base material,
2) erbium,
3) aluminum, and
4) fluorine, wherein the erbium is combined with at least some of the fluorine so that the erbium is surrounded by the fluorine; and
B) a cladding formed around the core.

### Claim 2 (depends on 1)

An improved optical waveguide as defined in claim 1, further wherein the erbium and at least some of the fluorine are combined in the form of erbium trifluoride (ErF.sub.3).

### Claim 3 (depends on 2)

An improved optical waveguide as defined in claim 2, further wherein the aluminum and at least some of the fluorine are combined in the form of aluminum trifluoride (AlF.sub.3).

### Claim 4

An improved optical waveguide having silicon dioxide as the base material, the improved optical waveguide comprising:
A) a core comprising:
1) at least one doping agent to increase the refractive index of the base material,
2) erbium,
3) boron, and
4) fluorine;
wherein the erbium is combined with at least some of the fluorine so that the erbium is surrounded by the fluorine; and
B) a cladding formed around the core.

### Claim 5

An improved optical waveguide having silicon dioxide as the base material, the improved optical waveguide comprising:
A) a core comprising:
1) at least one doping agent to increase the refractive index of the base material,
2) erbium,
3) fluorine, wherein the erbium is combined with at least some of the fluorine to form erbium trifluoride (ErF.sub.3) so that the erbium is surrounded by the fluorine;
4) an element capable of forming a compound that forms a complex with the erbium trifluoride; and
B) a cladding formed around the core.

### Claim 6 (depends on 5)

An improved optical waveguide as defined in claim 5, wherein the element capable of forming a compound that forms a complex with the erbium trifluoride is boron.

### Claim 7

A fiber-optic amplifier for amplifying an optical input signal received on a first optical waveguide (13) and for transmitting an amplified optical signal on a second optical waveguide (14), comprising:
A) a pumped light source (15);
B) an optical coupler connected to the first optical waveguide and the pumped light source for coupling the optical input signal with the output of the pumped light source; and
C) an amplifying optical waveguide (10) connected to the optical coupler and to the second optical waveguide for presenting an amplified optical signal of the optical input signal to the second optical waveguide, said amplifying optical waveguide having silicon dioxide as the base material, the said amplifying optical waveguide comprising:
1) a core comprising:
a) at least one doping agent to increase the refractive index of the base material,
b) erbium,
c) aluminum, and
d) fluorine, wherein the erbium is combined with at least some of the fluorine so that the erbium is surrounded by the fluorine; and
2) a cladding formed around the core.

### Claim 8

A fiber-optic amplifier for amplifying an optical input signal received on a first optical waveguide (13) and for transmitting an amplified optical signal on a second optical waveguide (14), comprising:
A) a pumped light source (15);
B) an optical coupler connected to the first optical waveguide and the pumped light source for coupling the optical input signal with the output of the pumped light source; and
C) an amplifying optical waveguide (10) connected to the optical coupler and to the second optical waveguide for presenting an amplified optical signal of the optical input signal to the second optical waveguide, said amplifying optical waveguide having silicon dioxide as the base material comprising:
1) a core comprising:
a) at least one doping agent to increase the refractive index of the base material,
b) erbium,
c) boron, and
d) fluorine, wherein the erbium is combined with at least some of the fluorine so that the erbium is surrounded by the fluorine; and
2) a cladding formed around the core.