Abstract

Single-mode silica optical fibers have been widely used as long-distance and high-speed communication media. However, inorganic glasses are not a universally ideal material especially for fiber connection and handling. The polymer optical fiber (POF) with a large core diameter (such as 0.5 mm or more) is one of the promising candidates to solve the serious problem in splicing the single-mode optical fiber having a small core diameter (5-10 µm). However, all commercially available POFs have been of the step-index (SI) type whose bandwidth of transmission is limited to about 5 MHz km due to modal dispersion. The key element for POF to go into the data transmission media would be, we believe, the large core-graded-index (GI) POF that combines an intrinsic high bandwidth. Very recently, such a GI POF whose bandwidth was about 2 GHz km was successfully prepared for the first time at Keio University. Although the transmission attenuation is relatively large (56–150 dB/km), it will cover the short range communication area within a few hundred meter, namely in a building, home, and customer premises.

© 1995 IEEE