Introduction to Single-mode Fiber Manufacturing. Your Optical Fiber Solutions Partner OFS Proprietary

Transcription

1 Introduction to Single-mode Fiber Manufacturing 1

2 Preform Manufacture Inside Vapor Deposition (IVD) Process Modified chemical vapor deposition (MCVD) Plasma enhanced chemical vapor deposition (PCVD) Outside deposition processes Outside vapor deposition (OVD) Vapor-phase axial deposition (VAD)

3 Preform Manufacture MCVD Process Used to fabricate complex fiber designs including: LaserWave (OM3 multimode fiber) TrueWave (Non-zero dispersion shifted fiber) Dispersion compensating fibers VAD Process Used to fabricate Zero Water Peak Singlemode Fiber: AllWave fiber AllWave FLEX fiber UltraWave fiber

4 OFS Modified Chemical Vapor Deposition (MCVD) Process End View Core Clad Refractive Index Profile Each layer sintered prior to deposition of the next layer Inside process is immune to contamination Results in superior control of Refractive Index Profile (therefore DMD & BW), Attenuation, Geometry

5 OFS Multimode Preform Manufacturing

6 Fiber Manufacturing Processes Vapor-phase axial deposition (VAD) Sintering Draw Tests and Measurements 6

7 VAD Core Technology 7

8 VAD Core Technology SiCl4 GeCl4 H2 O2 SiCl4 GeCl4 H2 O2 Simplicity for core manufacturing Better attenuation, core geometry 8

9 Fiber parameters primarily affected by deposition VAD Deposition Attenuation Attenuation uniformity and point discontinuities Fiber geometry Mode field diameter Core/clad concentricity Chromatic dispersion (more affected by design than manufacturing) Polarization mode dispersion (PMD) Affected by core ovality Reliability Affected by glass material purity 9

10 Sintering Fiber parameters primarily affected by sintering Attenuation (especially water peak performance) Locked in by deuterium bath Purification and Sinter Changes glass from crystalline to amorphous phase 10 1

11 Outside Vapor Deposition (OVD) Process VAD preform OVD Soot Deposition All Soot layers deposited prior to sintering OVD Torch Gas Mixture 11

12 Fiber Draw The sintered preform is loaded into a very high temp (> 2000 C) furnace The preform softens and is drawn down to the diameter of the cladding, 125 (μm) microns The glass is cooled to a temperature at which the acrylate coatings may be applied Very tight, complex quality controls needed 12

13 Fiber parameters primarily affected by draw Geometry Cladding diameter Coating geometry Cutoff wavelength Fiber curl Polarization mode dispersion (PMD) Affected by spinning process Reliability Affected by drawing environment and fiber handling Affected by coating performance Strippability Affected by coating cure 13

14 OFS Fiber Draw- Most modern Draw facility in the world (completed in 2002)

15 Manufacturing Strategy Based on Cylinder Technology Platform 2600 km VAD-in-Cylinder ZWPF preform made by OFS in 2003 Scalable to over 5000 km Synthetic Silica Cylinder VAD Rod PRESS RELEASE Norcross, GA, May 13, 2004 OFS, designer, manufacturer, and supplier of leading edge fiber optic products, today announced a multi-million dollar investment in fiber process technology at its Norcross, Georgia fiber manufacturing facility. This next generation fiber manufacturing technology will enable best-in-class performance, quality and cost for our AllWave fiber offering,

16 High Purity Synthetic Silica VS. Natural Quartz OFS fiber made with latest glass materials in Core and Cladding OFS uses high purity synthetic silica with: No alkali impurities => No risk of LWL hydrogen aging loss No particulate inclusions => No degradation of strength / low break frequency Figure 1. High purity synthetic silica fiber Figures 1 and 2 show SEM micrographs of fiber endfaces. In both cases the cleaved fiber surface was briefly etched in acid (48% HF for 3 minutes). Figure 2. Cheap natural quartz raw material fiber clearly shows many pits and imperfections. Acne like condition shows difference between pure and clean synthetic quartz vs natural quartz with its impurities and inclusions. 16

17 Tests & Measurement Prooftest 1% strain, 100 kpsi OTDR Fiber Pulley Pulley Length Attenuation, Attenuation Uniformity, Point Discontinuities Optical Pull ey Attenuation, Cutoff, Mode Field Diameter, Dispersion, PMD Geometry Weight Glass-- Core & Clad Diameter, Non-Circularity, Eccentricity Coating-- Diameter, Non-Circularity, Eccentricity Visual Inspection * Some measurements performed on a sampled basis due to stable performance 17