Larry Donalds began his career at Fiber Optic Center (FOC) in 2017 as Business Development, Fiber Design and Manufacturing, Technical Sales. Larry brings more than 35 years of experience from 3M Company in St. Paul, MN, after recently retiring. During his time with 3M Company, he spent 24 years in the development and manufacture of specialty optical fiber utilizing “voice of the customer,” helping 3M design and produce optical fibers to meet specific customer applications and performance criteria. Projects included the development and production of PM, PZ, EDFA (Erbium Doped Fiber Amplifier) fiber, radiation-hardened fiber for gyroscopes, solution doping of preforms, patent development for Oxyfluoride Erbium fiber, organometallic rare earth deposition and a rare earth single mode fiber bend and position sensor. In his fiber position at 3M, Larry maintained and operated MCVD equipment from SG Controls Ltd of Cambridge, England, whom FOC has represented in North America for over 25 years. Larry has achieved several awards during his career including 3M Golden Step Award, Photonics Circle of Excellence Award, R&D 100 Award, 3M Circle of Technical Excellence Awards in 1983, 2001 and 2008 and the 3M Ideation Challenge award in 2017. Larry and his wife reside in Arizona. Outside of FOC, Larry’s hobbies include fishing, boating, snowmobiling, outdoor landscaping, and deck design and construction.
This article continues FOC’s latest series on optical fiber manufacturing processes, providing an overview of coatings for a wide range of standard communication and specialty optical fibers. The main job of coatings is to protect the glass fiber, but there...
In this article, the latest in FOC’s series covering specialty fibers and their fabrication, we discuss polarization-maintaining (PM) fibers and the various approaches used to make them. There are several PM fiber designs – all quite different and each with it
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Objectives of the fiber drawing process -
The draw process takes a specialty fiber preform that may measure one meter in length and stretches it into hundreds of meters or even multiple kilometers of fiber. The preform is designed and fabricated with dopants and
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Since 2018, FOC has provided more than 10 articles on making fiber and preforms. One series of seven articles, launched in January 2018 and written by Larry Donalds, focuses on MCVD technology and issues in making preforms. The second series, started in July...
"Trial and error." These two words sum up my 24 years developing and manufacturing specialty preforms and fibers where I operated an MCVD gas delivery system. Our team was constantly testing new ideas to improve fiber strength and yield as well as the
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You can manufacture optical fiber preforms with a very basic system, essentially a gas delivery system in a room with an MCVD lathe. Or you can enhance your system by adding many accessories that will improve fiber strength and yield as well as the
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Ensure the gas deposition stream is tightly controlled
Prior to starting deposition, a key activity is ensuring the rotary seal is leak tight to prevent issues with fiber quality. In a previous article (“Comparing the 2 types of MCVD gas delivery systems”),
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Purchasing high-purity raw materials is critical to manufacturing quality preforms. How we handle our materials, tools, and equipment is equally important. For example, properly purging gas cylinder connections, properly
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As we all know, high-purity raw materials are critical to achieve design goals. Low metallic impurities prevent reflective loses, and dry raw materials prevent absorptions. In addition, there are many design tactics to meet cutoff wavelength, mode field diameter (MFD),...
If your company manufactures optical preforms – or is considering doing so – then you know the gas delivery system is critically important, because it controls the precise delivery of high-purity gases and chemical vapors. Prior to joining Fiber Optic Center
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