Quartz fibre with hydrogen barrier layer and method for the production thereof

Abstract

A quartz glass fibre includes a fibre core of quartz glass produced by modified chemical vapor deposition (MCVD). A fluorine-doped radial layer is provided on the fibre core. A cladding layer of quartz glass contains chlorine and covers the fluorine-doped radial layer to define a hydrogen barrier around the fibre core in response to being irradiated by defect-generating ultra-violet (UV) radiation. The cladding layer has at least one of a combination of E defects and non-bridging oxygen hole center (NBOHC) defects and a combination of SiOH and SiH compounds.

Claims

1. Quartz glass fibre, comprising: a) a fibre core of quartz glass produced by modified chemical vapor deposition (MCVD), b) a fluorine-doped radial layer on the fibre core, c) a cladding layer of quartz glass containing chlorine and covering the fluorine-doped radial layer to define a hydrogen barrier around the fibre core in response to being irradiated by defect-generating ultra-violet (UV) radiation, wherein d1) the cladding layer has E defects and non-bridging oxygen hole center (NBOHC) defects, or d2) the cladding layer has SiOH and SiH compounds.

2. The quartz glass fibre of claim 1, wherein the cladding layer is quartz glass having an a hydroxl (OH) concentration of 0.2 ppm, the chlorine having a content of 800-2000 ppm, and/or a refractive index of +0.3510.sup.3 to +0.510.sup.3 on the fibre core.

3. The quartz glass fibre of claim 1, wherein the cladding layer has a higher density of E defects and NBOHC defects than the fibre core.

4. The quartz glass fibre of claim 1, wherein the quartz glass fibre has no further doped layers.

5. The quartz glass fibre of claim 1, wherein the quartz glass fibre has no hermetic coating.

6. The quartz glass fibre of claim 1, wherein the quartz glass fibre is a multimode fibre.

7. The quartz glass fibre of claim 1, wherein the refractive index drop from the fibre core to the fluorine-doped region is 510.sup.3 to 1010.sup.3.

8. The quartz glass fibre of claim 1, wherein the quartz glass fibre does not comprise a carbon or metal layer.

9. The quartz glass fibre of claim 1, further comprising a polyacrylate layer provided over the cladding layer.

10. The quartz glass fibre of claim 1, wherein the quartz glass fibre does not have a silicon, boron nitride, C:H, or Si:H coating.

Description

FIGURES

[0127] The present disclosure will be further explained with reference to figures:

[0128] FIG. 1: Optical absorption bands of the known defects in quartz glass (see L. Skuja et al., Laser-induced color enters in silica Proc. SPIE vol. 4347, p. 1/14-14/14). Numbering: 1: fluoride groups SiF; 2: hydride groups SiH; 3: chloride groups SiCl; 4: oxygen vacancies (SiODC(I)); 5; hydroxyl groups SiOH; 6: peroxy bridge SiOOSi; 7: E* centers: SiSi=or=Si; 8: peroxy radicals SiOO; 9: SiODC(II) (divalent Si/O vacancy); 10: ozone O.sub.3; 11: interstitial Cl.sub.2; 12: non-bridging oxygen SiO; 13: interstitial oxygen O.sub.2; 14: self-trapped holes.

[0129] FIG. 2: FIG. 2: the reactions of E and NBOHC defects in quartz glass with hydrogen (see https://neup.inl.gov/SiteAssets/Final%20%20Reports/09-819% 20NEUP%20Final%20Report.pdf, page 28).

[0130] FIG. 3: Measured absorption of Suprasil F300 quartz glass and Suprasil 300 at 300 K as a function of radiant energy according to (see https://www.researchgate.net/profile/Giovanna_Navarra/publication/4155763_Absorption_edge_in_silica_glass/links/02e7e525fade3f17f2000000/Absorption-edge-in-silica-glass.pdf?origin=publication_detail).

[0131] FIG. 4: Schematic representation of the preform to be drawn before entering the drawing furnace with schematic representation of the coupling of the UV laser radiation. Reference signs: 1: UV laser radiation; 2: jacketing tube e.g. made of F300 quartz glass; 3: air gap between jacketing tube and primary preform; 4: primary preform with outer fluorine trench. FIG. 4 shows the primary preform inserted into the free jacketing tube. The angle of incidence is selected as described above.

[0132] FIG. 5: Schematic structure of the fibre drawing device for the production of hydrogen-insensitive fibres with high fibre strength and low fibre attenuation. Reference signs: 1: preform feed; 2: secondary preform consisting of jacketing tube and core preform for on-line jacketing; 3: drawing bulb in the hot furnace zone; 4: drawing furnace with immersed secondary preform; 5: coating unit; 6: drawing speed of the fibre; 7: glass fibre after leaving the drawing furnace; 8: quasi-axial UV laser irradiation into the cross-section of the jacketing tube.

CITED PUBLICATIONS

[0133] https://www.researchgate.net/profile/Giovanna_Navarra/publication/4155763_Absorption_edge_in_silica_glass/links/02e7e525fade3f17f2000000/Absorption-edge-in-silica-glass.pdf?origin=publication_detail [0134] https://www.lightbrigade.com/productionFiles/Resource-PDF/Whitepapers/Hermetic-Fiber-for-Oil-and-Gas. aspx [0135] http://www.dtic.mil/dtic/tr/fulltext/u2/a189886.pdf [0136] https://www.osti.gov/servlets/purl/14067 [0137] https://sundoc.bibliothek.uni-halle.de/diss-online/04/04H209/t3.pdf [0138] https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa. gov/19660007266.pdf [0139] https://www. crystran. co. uk/optical-materials/silica-glass-sio2 [0140] Joshua M. Jacobs, The impact of hydrogen on optical fibers, Corning White Paper, WP 9007 September 2004 [0141] (https://www.corning.com/media/worldwide/global/documents/sfiber%20WP9007_Hydrogen&20Aging.pdf) [0142] https://neup.inl.gov/SiteAssets/Final %20%20Reports/09-819%20NEUP%20Final%20Report.pdf [0143] https://www.heraeus.com/media/media/hqs/doc_hqs/products_and_solutions_8/optical_fiber/Fiber_Tubes_EN_2018_04.pdf [0144] Hibino et al., ESR Study on E-Centers Induced by Optical Fiber Drawing Process, Japanese Journal of Applied Physics, Volume 22, Part 2, Nr. 12 [0145] https://www.laserfocusworld.com/articles/print/volume-51/issue-04/features/fiber-optic-components-harsh-environment-optical-fiber-coatings-beauty-is-only-skin-deep.html [0146] https://www.researchgate.net/publication/253791167 [0147] Jing Yang, Numerical modeling of hollow optical fiber drawing, Dissertation 2008, Rutgers State University of New Jersey [0148] EP 95729 A2 [0149] L. Skuja et al., Laser-induced color enters in silica, Proc. SPIE vol. 4347, p. 1/14-14/14 [0150] A. K. Pandey et al., Refractive index profile design to improve hydrogen diffusion resistance property of optical fiber, ICOP 2009, International Conference on Optics and Photonics, India, November 2009 [0151] Troy et al., Role of hydrogen loading and glass composition on the defects generated by the femtosecond laser writing process of fiber Bragg gratings in Optical Materials Express 2 (11): 1663-1670 November 2012 [0152] DE69922728 T2, [0153] U.S. Pat. No. 4,276,243A, [0154] U.S. Pat. No. 4,412,853, und [0155] U.S. Pat. No. 4,582,480