Tac. Flipsen et al., POLYMER OPTICAL-FIBER WITH HIGH THERMAL-STABILITY AND LOW OPTICAL LOSSES BASED ON NOVEL DENSELY CROSS-LINKED POLYCARBOSILOXANES, Journal of applied polymer science, 67(13), 1998, pp. 2223-2230
A multimode step-index polymer optical fiber has been developed based
on a highly crosslinked polycarbosiloxane as the core material and a f
luorinated polyolefin (poly(fluoroethylene-co-fluoropropylene)-FEP) cl
adding layer. The combination offered a system with a high thermal sta
bility, both optically and dimensionally, up to at least 200 degrees C
. The polymer optical fiber was produced by injection of a poly(phenyl
methylvinylhydro)siloxane crosslinkable prepolymer in an FEP tubing, a
fter which the prepolymer was cured in situ. From attenuation measurem
ents losses as low as 0.98 dB/m at 780 nm were found. The refractive i
ndices of the core material and the cladding are 1.48 and 1.30, respec
tively. The large difference in refractive index results in a high val
ue for the numerical aperture of 0.70. The prepolymer is a single-comp
onent, self-crosslinking, and conveniently processable system. The com
bination of a low attenuation and easy processability makes these mate
rials very suitable not only for polymer optical fibers, but for all k
inds of optical components. (C) 1998 John Wiley & Sons, Inc.