BOC Offers Solutions To Reduce Low-Water-Peak Fiber Manufacturing Costs
The methods are described in a paper that Art Shirley, Ph.D., BOC's director of technology and commercialization, fiber optic solutions, will present at the event, to be held during session 9 on the afternoon of Tuesday, November 16.
"The presence of moisture in conventional fibers causes high levels of light attenuation along a portion of the fiber's transmission spectrum. 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 has historically eliminated wavelengths between 1360 and 1460 nanometers (about 30 percent of the available channels)," Shirley said.
Many fiber manufacturers are now focused on making LWPF as a means of providing the most light-carrying capacity for their products. Production volumes of LWPF are expected to show a compound annual growth rate of greater than 20 percent through 2007.
The manufacture of LWPF requires the careful control of moisture levels at every step in the fabrication and post treatment of the fiber so that the water peak attenuation is kept below 0.4 dB/km. A survey of LWPF available on the market shows that the typical measured water peak attenuation is between 0.31 and 0.35 dB/km.
"With careful regard for the elimination and prevention of moisture formation in the fiber, it is possible to achieve incremental hydroxyl attenuation losses at the water peak of less than 0.02 dB/km," Shirley said.
To make LWPF, conventional single-mode optical fiber (CSF) production processes must be modified to reduce or eliminate moisture in the raw materials and/or in the manufacturing processes - preform vapor deposition, drying and fiber drawing.
Shirley will discuss two of these methods in his paper: the use of ultra-high purity chlorine in soot drying, and consolidation and post-draw deuterium treatment of the fiber.
The BOC fiber optic solution group is dedicated to using its knowledge, skill and experience to solve the complex needs and challenges of optical fiber manufacturers. Since the late 1970s, BOC has been supplying high-purity gases, chemicals, equipment, services and technologies to the optical fiber manufacturing community.
The BOC Group (NYSE: BOX), the worldwide industrial gases, vacuum technologies and distribution services company, serves two million customers in more than 50 countries. It employs 44,500 people and had annual sales of over $7 billion in 2003. Further information about The BOC Group may be obtained on the Internet at http://www.boc.com.
Source: BOC