We downscale a lab-sized preform fabrication system to a benchtop miniature preform, hence short-length fiber fabrication system. The system is compact, low cost, fast and flexible as compared to standard preform fabrication processes. Using the proposed system incorporating with solution doping technique, we have successfully fabricated several ~ 1 mm thick, 40 ± 10 mm long Thulium doped silica and germania-silica preforms. The preforms were drawn to 400 µm diameter, sub-meter length low NA Thulium doped fibers. The technique is promising and suitable for rapid specialty optical fiber prototyping.
Technology Features, Specifications and Advantages
With the standard MCVD (Modified Chemical Vapour Deposition) fiber preform fabrication process, it often requires some 30 – 50 iteration (or more) to optimize a fabrication recipe. The bulk of preforms of the earliest iterations are often unsuitable for practical application and therefore wasted. As the early stages of fiber research involve experimenting with different glass hosts, dopants, mixture of dopants, doping concentrations, geometries, etc., small volumes of fiber are adequate for analyses. Therefore the proposed system is most suitable for small quantities specialty fiber prototyping.
The conventional process yields a 12 mm thick, 300 – 400 mm long preform that is used to draw to the required fiber. A single iteration from preform fabrication to fiber pulling takes approximately 2 working days. In contrast, our approach produces ~ 1 mm thick, 30 – 50 mm long preforms, which can be drawn to sub-meter length of fibers for initial testing and analyses. A single iteration of this process takes about 2 – 3 hours, which reduces excess time, cost and materials for greater research efficacy.
This system can be adopted for initial analyses until the desired doping solution composition and / or glass host selection, etc., is found. Standard fabrication can then be employed for the production of longer and higher quality fibers. It complements the existing fiber fabrication processes.
The system can be used in the fiber research and development industries for cost effective initial rapid prototyping. It can also be used for flexible post fiber processing for any fiber related applications, such as tapering, recoating, etc. In addition, the system can also serve as an education toolkit for the fiber related processes.
This process is beneficial for acquiring small quantities of specialty optical fibers for rapid prototyping purposes, and especially so for the less mature optical fiber fabrication, such as rare earth doped or soft-glasses fibers. It also opens up the possibilities of exploring other exotic glass hosts with various material choices and compositions on a smaller scale.