BOC to use Deuterium gas mixing technology for low water peak fiber manufacture

17 July 2003 Murray Hill, NJ Lightwave -- Industrial gas and vacuum technologies company BOC is using its patented Spectra-Blend gas mixing technology to provide optical fiber manufacturers with precise concentrations and reliable supply of high-purity deuterium gas for use in producing low water peak fiber.

Low water peak fiber, which has significantly more light-carrying/data transmission capacity than conventional fiber, is the latest step in optical fiber product evolution, say BOC representatives. Demand for the product is growing, and many optical fiber manufacturers are racing to meet their customers' needs.

"The presence of moisture in conventional fibers causes high levels of light attenuation along a portion of the fiber's transmission spectrum," explains Art Shirley, Ph.D., director of commercialization and technology, fiber optics solutions, BOC. "This 'water peak' is primarily due to hydrogen, which readily diffuses through the glass matrix of an optical fiber. It is trapped at defects in the glass structure and causes light attenuation at wavelengths between 1360 and 1460 nanometers."

To manufacture low water peak fibers, water levels in the fiber are reduced from 10 parts-per-billion (ppb) to less than 1 ppb. One process exposes fiber to deuterium gas at elevated temperature and pressure. Concentrated deuterium, dilute deuterium (less than 10 percent) in nitrogen, or other custom deuterium blends are also used in the process.
"Deuterium atoms displace hydrogen atoms from the defect sites," adds Shirley. "This lowers the water peak and increases the light carrying/data transmission capability of the fiber."

Using Spectra-Blend gas mixing technology allows BOC to supply optical fiber manufacturers with high-purity, zero-tolerance deuterium mixtures with no cylinder-to-cylinder or lot-to-lot variation. BOC can also supply solutions integrating high-purity deuterium gas supply with a BOC system to safely blend customized deuterium mixtures onsite and deliver them to their point-of-use. BOC claims its proprietary gas-blending process allows precise, flexible, and real-time control of deuterium mixing for use in multiple deuteration chambers.

"This solution improves supply reliability for our customers," asserts Glenn Rush, vice president, fiber optic solutions, BOC. "It also reduces the costs and risks inherent with handling numerous cylinders of deuterium or deuterium mixtures at their facility. To help fiber manufacturers reduce costs, BOC can also use its gas recovery technology to recycle unused deuterium from batch to batch," he notes. "These solutions demonstrate BOC's ability to help optical fiber manufacturers improve their competitive position and reduce their total cost of ownership."