Process for producing optical transmission fiber

• US 4,161,505 A
• Filed: 01/14/1976
• Issued: 07/17/1979
• Est. Priority Date: 11/25/1972
• Status: Expired due to Term

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Shiraishi, Satoshi, Fujiwara, Kunio, Kurosaki, Shiro
• Primary Examiner(s): Pianalto, Bernard D.
• Application Number:
  US05/648,997
• Time in Patent Office: 1,280 Days
• Field of Search: 427/163, 427/166, 427/167, 427/346, 427/376, 65/3 A, 264/171
• US Class Current: 264/1.27
• CPC Class Codes: B29D 11/00663 Production of light guides
• CPC Class Codes: C03B 2201/02 Pure silica glass, e.g. pure fused quartz
• CPC Class Codes: C03B 2201/08 doped with boron or fluorine or other refractive index decreasing dopant
• CPC Class Codes: C03B 2201/10 doped with boron C03B2201/14 takes precedence
• CPC Class Codes: C03B 2201/12 doped with fluorine C03B2201/14 takes precedence
• CPC Class Codes: C03B 2203/16 Hollow core
• CPC Class Codes: C03B 2203/22 Radial profile of refractive index, composition or softening point
• CPC Class Codes: C03B 2207/86 by bubbling a gas through the liquid
• CPC Class Codes: C03B 23/207 Uniting glass rods, glass tubes, or hollow glassware C03B23/24 takes precedence
• CPC Class Codes: C03B 37/01211 by inserting one or more rods or tubes into a tube
• CPC Class Codes: C03B 37/01413 Reactant delivery systems C03B37/01807 takes precedence; devices therefor in general B01D1/00, B01J4/00
• CPC Class Codes: C03B 37/01446 Thermal after-treatment of preforms, e.g. dehydrating, consolidating, sintering C03B37/01853 takes precedence
• CPC Class Codes: C03B 37/01807 Reactant delivery systems, e.g. reactant deposition burners
• CPC Class Codes: C03B 37/027 Fibres composed of different sorts of glass, e.g. glass optical fibresC03B37/0253, C03B37/028 take precedence
• CPC Class Codes: C03C 13/045 Silica-containing oxide glass compositions
• CPC Class Codes: G02B 6/02 Optical fibres with cladding with or without a coating
• CPC Class Codes: G02B 6/03611 Highest index adjacent to central axis region, e.g. annular core, coaxial ring, centreline depression affecting waveguiding
• CPC Class Codes: G02B 6/03627 arranged - +
• CPC Class Codes: Y10S 65/16 Optical filament or fiber treatment with fluorine or incorporating fluorine in final product

Abstract

A process for producing an optical transmission fiber is provided which comprises feeding highly pure halides, hydrides or organic compounds of Si and B by way of carrier gas on the outer surface of a fused silica rod or a fused silica pipe, or inner surface of a fused silica pipe, oxidizing them and depositing the products to form a pure fused silica layer or a doped fused silica layer containing B₂ O₃, melting the pipe and the deposited layer followed by a spinning. The SiO₂ layer can alternatively contain fluorine instead of B₂ O₃. A further SiO₂ layer can be deposited thereon to improve the spinning processability and lower the index of refraction of the B₂ O₃ containing layer.

Claims

1. A process for producing an optical transmission fiber, comprising (A) oxidizing halides, hydrides or organic compounds of Si with OF₂ or oxygen containing a gaseous fluorine compound, or (B) by the oxidation of SiF₄ to form doped fused silica containing F and depositing said doped fused silica containing F as a layer on the outer surface of a rod or pipe or pure fused silica and melting and spinning said rod or pipe having said deposited layer into a fiber.

2. The process for producing an optical transmission fiber of claim 1, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

3. The process for producing an optical transmission fiber of claim 1, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

39. The process for producing an optical transmission fiber of claim 1, wherein said process comprises after said depositing, heating and melting said layer deposited on said rod in a vacuum to eliminate gas bubbles.

40. The process for producing an optical transmission fiber of claim 1, wherein said process comprises, after the deposition, heating and melting said deposited layer on said rod while applying supersonic waves to said layer to eliminate gas bubbles therefrom.

4. A process for producing an optical transmission fiber, comprising (A) oxidizing halides, hydrides or organic compounds of Si with OF₂ or oxygen containing a gaseous fluorine compound, or (B) by the oxidation of SiF₄ to form doped fused silica containing F and depositing said doped fused silica containing F as a layer on the outer surface of a pure fused silica rod or pipe and inserting said rod or pipe into a second pipe of a doped fused silica containing F and then melting and spinning said second pipe having said rod or said first pipe therein into a fiber.

5. The process for producing the optical transmission fiber of claim 4 wherein said process comprises after forming said doped layer, heating and melting said layer in a vacuum to eliminate gas bubbles.

6. The process for producing an optical transmission fiber of claim 4 wherein said process comprises after forming said doped layer, heating and melting said layer while applying supersonic waves to said layer to eliminate gas bubbles therefrom.

7. A process for producing an optical transmission fiber comprising (A) oxidizing halides, hydrides or organic compounds of Si with OF₂ or oxygen containing a gaseous fluorine compound, or (B) by the oxidation of SiF₄ to form doped fused silica containing F and depositing said doped fused silica containing F as a layer and next a fused silica or water-repellent glass layer on a rod or pipe of pure fused silica and melting and spinning said rod or pipe having said layers deposited thereon into a fiber.

8. The process for producing the optical transmission fiber of claim 7 wherein said process comprises after forming said doped layer, heating and melting said layer in a vacuum to eliminate gas bubbles.

9. The process for producing an optical transmission fiber of claim 7 wherein said process comprises after forming said doped layer, heating and melting said layer while applying supersonic waves to said layer to eliminate gas bubbles therefrom.

10. The process for producing an optical transmission fiber of claim 7, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

11. A process for producing an optical transmission fiber, comprising (A) oxodizing halides, hydrides or organic compounds of Si with OF₂ or oxygen containing a gaseous fluorine compound, or (B) by the oxidation of SiF₄ to form doped fused silica containing F and depositing said doped fused silica containing F as a layer on the outer surface of a rod or pipe of pure fused silica and inserting said rod or pipe into a second pipe of fused silica or water-repellent glass and melting and spinning said second pipe having said rod or said first pipe therein into a fiber.

12. The process for producing the optical transmission fiber of claim 11 wherein said process comprises after forming said doped layer, heating and melting said layer in a vacuum to eliminate gas bubbles.

13. The process of producing an optical transmission fiber of claim 11 wherein said process comprises after forming said doped layer, heating and melting said layer while applying supersonic waves to said layer to eliminate gas bubbles therefrom.

14. The process for producing an optical transmission fiber of claim 11, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

15. A process for producing an optical transmission fiber comprising (A) oxidizing halides, hydrides or organic compounds of Si with OF₂ or oxygen containing a gaseous fluorine compound, or (B) by the oxidation of SiF₄ to form doped fused silica containing F and depositing said doped fused silica containing F as a layer on the outer surface of a pure fused silica rod or pipe and placing said rod or pipe inside a doped fused silica second pipe containing F, inserting said second pipe into a third pipe of fused silica or water-repellent glass and then melting and spinning said third pipe containing said second pipe and said first pipe or tube into a fiber.

16. The process for producing the optical transmission fiber of claim 15 wherein said process comprises after forming said doped layer, heating and melting said layer in a vacuum to eliminate gas bubbles.

17. The process of producing an optical transmission fiber of claim 15 wherein said process comprises after forming said doped layer, heating and melting said layer while applying supersonic waves to said layer to eliminate gas bubbles therefrom.

18. The process for producing an optical transmission fiber of claim 15, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

19. A process for producing an optical transmission fiber comprising (A) oxidizing halides, hydrides or organic compounds of Si with OF₂ or oxygen containing a gaseous fluorine compound, or (B) by the oxidation of SiF₄ to form doped fused silica containing F and depositing said doped fused silica containing F as a layer on the outer surface of a pipe of fused silica or water-repellent glass having on the inner surface of said pipe a layer of doped fused silica containing F formed in the same manner as said outer layer and on the inner surface of said layer a layer of pure fused silica and melting and spinning said pipe into a fiber.

20. The process for producing the optical transmission fiber of claim 19 wherein said process comprises after forming said doped layer, heating and melting said layer in a vacuum to eliminate gas bubbles.

21. The process of producing an optical transmission fiber of claim 19 wherein said process comprises after forming said doped layer, heating and melting said layer while applying supersonic waves to said layer to eliminate gas bubbles therefrom.

22. The process for producing an optical transmission fiber of claim 19, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

23. A process for producing an optical transmission fiber comprising inserting a pure fused silica rod or a pure fused silica rod having thereon a doped fused silica layer containing F formed by (A) oxidizing halides, hydrides or organic compounds of Si with OF₂ or oxygen containing a gaseous fluorine compound, or (B) by the oxidation of SiF₄ to form doped fused silica containing F and depositing said doped fused silica containing F as a layer on the outer surface of a pure fused silica rod into a pipe of fused silica or water-repellant glass having on its inner surface a doped fused silica layer containing F formed in the same manner as said doped fused silica layer and melting and spinning said pipe containing said rod into a fiber.

24. The process for producing the optical transmission fiber of claim 23 wherein said process comprises after forming said doped layer, heating and melting said layer in a vacuum to eliminate gas bubbles.

25. The process of producing an optical transmission fiber of claim 23 wherein said process comprises after forming said doped layer, heating and melting said layer while applying supersonic waves to said layer to eliminate gas bubbles therefrom.

26. The process for producing an optical transmission fiber of claim 23, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

27. A process for producing an optical transmission fiber comprising inserting a pure fused silica rod into a pipe of a doped fused silica containing F, inserting said pipe into a second pipe of fused silica or water-repellent glass and melting and spinning said second pipe containing said first pipe containing said rod into a fiber.

28. The process for producing an optical transmission fiber of claim 27, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

29. A process for producing an optical transmission fiber comprising alternatingly depositing a doped fused silica layer containing F and a pure fused silica layer and further a doped fused silica layer containing F onto the inner surface of a pipe of fused silica or water-repellent glass and melting and spinning said pipe into a fiber, each of said doped fused silica layers being formed by (A) oxidizing halides, hydrides or organic compounds of Si with OF₂ or oxygen containing a gaseous fluorine compound, or (B) by the oxidation of SiF₄ to form doped fused silica containing F and depositing said doped fused silica containing F as a layer.

30. The process for producing the optical transmission fiber of claim 29 wherein said process comprises after forming said doped layer, heating and melting said layer in a vacuum to eliminate gas bubbles.

31. The process of producing an optical transmission fiber of claim 29 wherein said process comprises after forming said doped layer, heating and melting said layer while applying supersonic waves to said layer to eliminate gas bubbles therefrom.

32. The process for producing an optical transmission fiber of claim 29, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

33. A process for producing an optical transmission fiber comprising inserting a rod of doped fused silica containing F into a pipe of fused silica or water-repellent glass having deposited on its inner surface a doped fused silica layer formed by (A) oxidizing halides, hydrides or organic compounds of Si with OF₂ or oxygen containing a gaseous fluorine compound, or (B) by the oxidation of SiF₄ to form fused silica containing F and depositing said doped fused silica containing F as a layer on the inner surface of said pipe and next a pure fused silica layer and melting and spinning said pipe containing said rod into a fiber.

34. The process for producing the optical transmission fiber of claim 33 wherein said process comprises after forming said doped layer, heating and melting said layer in a vacuum to eliminate gas bubbles.

35. The process of producing an optical transmission fiber of claim 33 wherein said process comprises after forming said doped layer, heating and melting said layer while applying supersonic waves to said layer to eliminate gas bubbles therefrom.

36. The process for producing an optical transmission fiber of claim 33, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.

37. A process for producing an optical transmission fiber comprising inserting a rod of doped fused silica containing F inside a pure fused silica pipe, inserting said pipe containing said rod inside a second pipe of doped fused silica and inserting said second pipe containing said first pipe containing said rod into a third pipe of fused silica or water-repellent glass and then melting and spinning said third pipe containing said second pipe containing said first pipe containing said rod into a fiber.

38. The process for producing an optical transmission fiber of claim 37, wherein said fiber exhibits a refractive index which varies between the periphery and the central longitudinal axis of said fiber, said variation being symmetrical with respect to the central longitudinal axis of the fiber.