Solution doping adds erbium and other rare earths into a glass core. If the ratio of the doped core to the preform outside diameter is too large, undesirable optical properties will be obtained. Correcting the incorrect ratio will also yield more drawn fiber. Collapsing another glass tube onto the preform can correct the core-to-clad ratio. If more ratio change is needed and a larger diameter is not drawable, preform stretching can be used to reduce the core diameter, followed by an additional over-collapse. I wrote active Excel programs for technicians, which calculated the over-collapse and stretch diameters to achieve the required core-to-clad ratio to meet optical specifications in drawn fibers. This process can increase erbium fiber yield per preform by a factor of 5 or better.
Additional resources from the FOC team include:
- Category Resource
- View the Glossary, Acronyms, Military Specifications for Connectors
- Q&A Resource: email technical questions to AskFOC@focenter.com
Have questions about this FOC Tip?
Contact FOC with questions at: (800) 473-4237 / 508-992-6464 or email: FiberOpticCenter@focenter.com and we will respond ASAP.
Additional articles from our preform fabrication consultant include:
- MCVD Tips: 14 ideas to enhance preform strength, yield, and reproducibility
- MCVD Options: These add-on features can enhance your optical fiber preform strength,
yield, and reproducibility - Controlling the optical fiber preform deposition process
- Preparing to Manufacture an Optical Fiber Preform
- Critical Design Goals to Manufacture Optical Fiber Preforms
- Comparing the 2 types of MCVD gas delivery systems to manufacture optical preforms: Stainless steel and Teflon/glass
- Attention specialty fiber manufacturers: Take advantage of FOC’s preform fabrication consulting to troubleshoot your system and achieve reproducibility and high yields
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