EP0078749A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Reinforced and chemically resistant optical filament
Assignee: SLB NV
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Filing: 1982-11-02
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Granted: —
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Expires: 2002-11-02
Abstract
Abstract This invention relates to an improved optical filament waveguide providing increased strength and resistance to moisture and chemical attack. This Improved optical filament waveguide is particularly useful in the severe environment encountered in wellbore logging operations. This optical filament waveguide is the result of coating, preferably at a temperature below 500°C, an optical filament rod with a relatively thin protective coating of a metal oxide whose coefficient of thermal expansion is of the same order of magnitude as that of the rod.
Inventors
- 👤 Tryggve Baak
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 00:39
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/44; G02B6/4401; G02B6/4429; G02B6/443; C; C03; C03C; C03C25/00; C03C25/10; C03C25/104; C03C25/106; C03C25/1061; C03C25/1063; C03C25/12; C03C25/22; C03C25/223
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
123 words
A method of producing a mechanically and chemically resistant optical filament waveguide, characterized by: drawing an optical filament waveguide rod from a preform in a clean and dry environment; and applying at a temperature less than substantially 500°C a protective coating of a metal oxide around the periphery of said rod immediately after said drawing, said metal oxide having a coefficient of thermal expansion within substantially one order of magnitude of the coefficient of thermal expansion of the periphery of said rod and said metal oxide coating being thin relative to the diameter of said rod and providing better resistance to chemical attack by water and other corrosive chemicals and to mechanical attack by abrasion and stress than the periphery of said rod.
Claim 2
Independent Claim
123 words
A method of producing a mechanically and chemically resistant optical filament waveguide, characterized by: drawing an optical filament waveguide rod from a preform in a clean and dry environment; and applying at a temperature less than substantially 500°C a protective coating of a metal oxide around the periphery of said rod immediately after said drawing, said metal oxide having a coefficient of thermal expansion within substantially one order of magnitude of the coefficient of thermal expansion of the periphery of said rod and said metal oxide coating being thin relative to the diameter of said rod and providing better resistance to chemical attack by water and other corrosive chemicals and to mechanical attack by abrasion and stress than the periphery of said rod.
Claim 3
Dependent Claim
15 words
The method of claim 1 characterized in that said rod comprises a silica-containing glass rod.
Claim 4
Dependent Claim
30 words
The method of claim 1 or 2 characterized in that said protective coating is selected from the oxides of tetravalent tin, titanium, zirconium, hafnium or the polycrystalline double oxides thereof.
Claim 5
Dependent Claim
30 words
The method of claim 2, 3 or 4 characterized in that said protective coating of the metal oxide is characterized by a radial thickness of less than about one-half micrometer.
Claim 6
Dependent Claim
33 words
The method of claim 1, 2, 3 or 4 characterized in that said metal oxide is selected from tin oxide, titanium dioxide, zirconium dioxide, hafnium dioxide, zirconium-hafnium double oxides or hafnium-titanium double oxides.
Claim 7
Dependent Claim
31 words
The optical filament waveguide of claim 5 characterized by: a second protective coating around the periphery of said metal oxide coating, said second protective coating comprising a metallic or resin film.
Claim 8
Dependent Claim
18 words
A mechanically and chemically resistant optical filament waveguide produced by the process of any one of claims 1-6.
Claim 9
Dependent Claim
139 words
An optical filament waveguide, characterized by: a rod transparent to a preselected range of electromagnetic radiation and having a first index of refraction in the core thereof and a different index of refraction at the periphery thereof such that said electromagnetic radiation will propagate along the longitudinal axis of said rod; and a thin protective coating of a zirconia-containing glass around the periphery of said rod, the radial thickness of said coating being thin relative to the diameter of said rod, and the coefficient of thermal expansion of said zirconia-containing glass being within substantially one order of magnitude of the coefficient of thermal expansion of the periphery of said rod, said protective coating providing better resistance to chemical attack by water and other corrosive chemicals and to mechanical attack by abrasion and stress than the periphery of said rod.
Claim 10
Dependent Claim
139 words
An optical filament waveguide, characterized by: a rod transparent to a preselected range of electromagnetic radiation and having a first index of refraction in the core thereof and a different index of refraction at the periphery thereof such that said electromagnetic radiation will propagate along the longitudinal axis of said rod; and a thin protective coating of a zirconia-containing glass around the periphery of said rod, the radial thickness of said coating being thin relative to the diameter of said rod, and the coefficient of thermal expansion of said zirconia-containing glass being within substantially one order of magnitude of the coefficient of thermal expansion of the periphery of said rod, said protective coating providing better resistance to chemical attack by water and other corrosive chemicals and to mechanical attack by abrasion and stress than the periphery of said rod.
Claim 11
Dependent Claim
93 words
The optical filament waveguide of claim 13 characterized by: a second thin protective coating of a metal oxide around the periphery of said zirconia-containing glass, said metal oxide selected from tin dioxide, titanium dioxide, zirconium dioxide, hafnium dioxide, zirconium-hafnium double oxides or hafnium-titanium double oxides and said metal oxide coating being characterized by having a thin radial thickness relative to the diameter of said rod and by having a coefficient of thermal expansion being within substantially one order of magnitude of the coefficient of thermal expansion of said rod and said zirconia-containing glass.
Claim 12
Dependent Claim
116 words
An optical filament waveguide, characterized by: a rod transparent to a preselected range of electromagnetic radiation and having a first index of refraction in the core thereof and a different index of refraction at the periphery thereof such that said electromagnetic radiation will propagate along the longitudinal axis of said rod; and a protective coating of a polycrystalline double metal oxide wherein the metals are selected from the group consisting of tin, titanium, zirconium and hafnium, said metal oxide having a coefficient of thermal expansion within substantially one order of magnitude of the coefficient of thermal expansion of the periphery of said rod and said protective coating being thin relative to the diameter of said rod.
Claim 13
Dependent Claim
116 words
An optical filament waveguide, characterized by: a rod transparent to a preselected range of electromagnetic radiation and having a first index of refraction in the core thereof and a different index of refraction at the periphery thereof such that said electromagnetic radiation will propagate along the longitudinal axis of said rod; and a protective coating of a polycrystalline double metal oxide wherein the metals are selected from the group consisting of tin, titanium, zirconium and hafnium, said metal oxide having a coefficient of thermal expansion within substantially one order of magnitude of the coefficient of thermal expansion of the periphery of said rod and said protective coating being thin relative to the diameter of said rod.
Claim 14
Dependent Claim
31 words
ll. The optical filament waveguide of claim 10 characterized in that said double metal oxide is selected from the group consisting of the zirconium-hafnium double oxides and the hafnium-titanium double oxides.
Claim 15
Independent Claim
241 words
An apparatus for coating a linear body with a protective coating of a metal oxide, characterized by: a reaction chamber through which said body is moved in a direction parallel to its linear dimension, said reaction chamber having entrance and exit ports of sufficient size and shape so as not to contact said body; means for supplying a gaseous metal halide in a carrier gas to said reaction chamber in a restricted zone, wherein the housing of said restricted zone is of sufficient size and shape so as not to contact said body and wherein said restricted zone is constructed so as to promote the flow of said metal halide and carrier gas out of said restricted zone in a direction opposite to the movement of said linear body; means for supplying gaseous water or hydrogen peroxide in a carrier gas to said reaction chamber between said restriced zone and said reaction chamber exit port at a pressure sufficient to flow said carrier gas and entrained materials in a direction opposite to the movement of said linear body; means for exhausting said carrier gases and other entrained materials from said reaction chamber, said means located between said reaction chamber entrance port and said restricted zone; and means for heating said reaction chamber to a temperature sufficient to react said metal halide with said water or said hydrogen peroxide to produce to produce the desired metal oxide coating on said linear body.
Claim 16
Independent Claim
241 words
An apparatus for coating a linear body with a protective coating of a metal oxide, characterized by: a reaction chamber through which said body is moved in a direction parallel to its linear dimension, said reaction chamber having entrance and exit ports of sufficient size and shape so as not to contact said body; means for supplying a gaseous metal halide in a carrier gas to said reaction chamber in a restricted zone, wherein the housing of said restricted zone is of sufficient size and shape so as not to contact said body and wherein said restricted zone is constructed so as to promote the flow of said metal halide and carrier gas out of said restricted zone in a direction opposite to the movement of said linear body; means for supplying gaseous water or hydrogen peroxide in a carrier gas to said reaction chamber between said restriced zone and said reaction chamber exit port at a pressure sufficient to flow said carrier gas and entrained materials in a direction opposite to the movement of said linear body; means for exhausting said carrier gases and other entrained materials from said reaction chamber, said means located between said reaction chamber entrance port and said restricted zone; and means for heating said reaction chamber to a temperature sufficient to react said metal halide with said water or said hydrogen peroxide to produce to produce the desired metal oxide coating on said linear body.
Claim 17
Dependent Claim
21 words
The apparatus of claim 12 characterized in that said carrier gases and entrained materials enter the reaction chamber in annular streams.
Claim 18
Dependent Claim
58 words
The apparatus of claim 12 or 13 characterized by a drying chamber through which the linear body passes prior to entering the reaction chamber, wherein said drying chamber has entrance and exit ports of sufficient size and shape so as not to contact said body and has means for supplying and exhausting a dry gas under an overpressure.
References Cited (Backward Citations)
GB1420315A
Cited
US4184860A
Cited
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