The research of an optical fiber array, using polymer composites, which use as an optical interconnection between planar lightwave circuit device and multichannel optical fiber was accomplished.
Optical fiber array has to satisfy low optical loss requirement less than 0.4 dB as a temperature change. For the purpose of this, a parameter being able to set up design criteria of materials for an optical fiber array was derived and this parameter was verified using the finite element analysis.
Material requirements for optical fiber array were presented using the design parameter and these were the coefficients of thermal expansion less than 10 × 10E-6/℃ and elastic modulus more than 20 GPa. The material with short carbon fiber epoxy composites and silica particulate epoxy composites was designed by thermomechnical properties such as coefficient of thermal expansion, elastic modulus and stress relaxation.
The coefficient of thermal expansion and elastic modulus of short carbon fiber epoxy composites can be controlled by the fiber volume fraction and fiber length. The material condition with the coefficients of thermal expansion less than 10 ×10E-6/℃ and elastic modulus more than 20 GPa were obtained at the fiber volume fraction 45% and fiber length 1.6 mm.
The coefficient of thermal expansion of silica particulate epoxy composites was not mostly affected by size of silica particles, but was dominated by volume fraction of silica particles. And coefficients of thermal expansion less than 10 ×10E-6/℃ was obtained at volume fraction 76%. The elastic moludus of silica particulate epoxy composites was affected by size and volume fraction of silica particles. And the elastic moludus more than 20 GPa was obtained on the particle size less than 10㎛and volume fraction more than 76%.
Using silica particulate epoxy composites with the volume fraction 76%, 8-channel optical fiber array having less than dimensional tolerances 1㎛ was manufactured by transfer molding technique using molding dies with uniquely-designed core pin and precisely-machined zirconia ceramic V block. This optical fiber array was shown optical loss variations within 0.4 dB on thermal cycling test of -40℃ ∼ +75℃ and high temperature test at 80℃.
