PNIPU: High-precision measuring complex for determining the quality of optical fiber blanks

2022: Discovery of a way to improve the quality of fiber

Perm Polytechnic scientists have found an economical way to improve the quality of fiber. This became known in November 2022.

Measurement diagram in the presence of a billet standard

Fiber light guides are used in multi-channel information transmission systems, cable television, communication, local area networks, telemechanics and medicine. They are created on the basis of glass "blanks," to which impurities from rare-earth metals are added. To ensure the quality of future light guides, the production process must be controlled at each stage. Scientists of the Perm Polytechnic with colleagues from the Ural Branch of the Russian Academy of Sciences have developed an automated complex that monitors the uniformity of the deposition of such metals. This allows you to use only high-quality blanks and reduce the funds of enterprises.

Circuit diagram of the device

Specialists from the Perm Federal Research Center of the Ural Branch of the Russian Academy of Sciences also took part in the work.

Fiber optic fiber production is complex and expensive due to raw material prices and equipment operating costs. At the initial stage of manufacture, glass blanks are used. Impurities from rare-earth metals are applied on them. It is important to monitor whether they are evenly distributed on the quartz pipe. For this purpose automated complex of luminescent photometry is used, which determines concentration of metals. We have developed a computing and control system for it. This made it possible for the first time to create a high-precision measuring complex to determine the quality of blanks at the initial stage of their production, "explained Konstantin Latkin, one of the developers, senior lecturer at the Department of General Physics at Perm Polytechnic.

Circuit diagram of the automated system for monitoring uniformity of active impurity concentration

The technologies that had previously been used for these purposes allowed only the fibers to be examined or the quality to be tracked outside the initial production stages. Some of the methods involved the use of toxic and fire-hazardous liquids and required subsequent cleaning of the parts.

Measurements of the control system with additional calculations help to "reject" poor-quality light guide blanks and not use them at expensive production stages. Our development allows you to significantly save the costs of enterprises and reduce the production cycle time. The computer system made it possible to achieve accurate measurements with an error of 5%, - said the researcher.

The units were assembled in the laboratory of PFIC URO RAS and can be used at industrial enterprises that mass-produce fiber light guides.