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NIST And Your Communications Lines |
NIST has developed many of the manufacturing and measurement standards of optical fibers without which the vast, reliable and rapidly growing optical communication systems would be impossible. |
A growing mesh of optical fiber
carries more and more of the world's telecommunications traffic every month. Almost all
long distance traffic now travels via optical fibers. Local telecommunication also is
becoming increasingly fiberized. Building a dependable system with millions of interlinked
kilometers of hair thin optical fiber, all of it made from exquisitely pure glass
formulations, has been no easy feat. Vanishing amounts of contaminants, tiny mismatches in
fiber diameters or fiber-to-fiber alignments, and even slightly inaccurate measurements of
the amount that pulses of light spread out as they travel down fibers, all can turn the
global fiber mesh into a useless mess. Since 1981, the National Institute of Standards and Technology (NIST) has been working closely with industry to develop many of the manufacturing and measurement standards without which a vast and reliable optical communication system would be impossible. For example, the joining of optical fibers requires the fibers to have accurately controlled dimensions. NIST developed reference materials that fiber manufacturers rely upon for calibrating factory floor instruments used to measure the width of the glass sleeve (cladding) that surrounds the central core in which the light travels. The slightest inaccuracies or variability from measurement to measurement could lead to glass fibers better suited for insulation than communication. NIST also continues to develop the standards and measurement methods required to build optical fiber systems of ever greater ability. For example, the velocity of light in a fiber varies with its wavelength (color), which means that a pulse of light containing several wavelengths will spread out (disperse) as it goes. This kind of dispersion sets the ultimate limit to the rate at which information can be transmitted. NIST currently is developing methods for measuring this and other kinds of dispersion. |
| Links: | Learn more about an important
manufacturing aid that NIST developed in collaboration with the fiber
optic industry.
Take a look at NIST's Optical Fiber and Components Group and their Optical Fiber Metrology Project. The group is just part of NIST's Electronics and Electrical Engineering Laboratory. |