In this paper, a 850nm-optimized dispersion-unshifted single-mode optical fiber was introduced. This type of
fiber is completely compatible with G652 series fibers, but its bandwidth at 850nm wavelength has been
optimized in order to fitting the potential applications. This fiber was manufactured by PCVD (Plasma-active
Chemical Vapor Deposition) method. In order to increasing the 850nm bandwidth, the core-RI-profile (Refractive
Index) of this fiber was designed as graded-index profile. With a piece of about 36km length fiber, some relevant
geometric and optical characteristics had been got. The core diameter, MFD (Mode Field Diameter) was about 13
micron and 9.6 micron respectively. The cut-off wavelength and zero-dispersion wavelength was at 1315nm and
1323nm nearly. The attenuation at 1310nm and 1550nm was less than 0.34dB/km and 0.19dB/km respectively.
With all of these results, this 850nm-optimized fiber was completely corresponding with specifications of G652
series of fibers. Meanwhile, OFLB (Over-Filled Launch Bandwidth) test showed the bandwidth at 850nm was
larger than 400MHz.km comparing to about 150MHz.km OFL bandwidth of normal G652 fiber. Because of the
pretty large 850nm bandwidth, this fiber could be possibly used at 850nm wavelength in LAN (Local Area
Network) or DSN (Data-Storage Network) field. In order to validating the compatibility with G652 fibers, the
splice loss between this fiber and normal G652 fiber also had been tested.