Temperature dependence of return loss for optical fiber connectors with refractive index-matching material

This letter describes the temperature dependence of return loss for optical fiber connectors with refractive index-matching material. We have performed return loss calculations and experiments for mated flat endface plugs whose fiber endfaces had a high index layer. We used index-matching material with a refractive index of 1.467 at 20/spl deg/C and a thermal coefficient of -2.9/spl times/10/sup -4///spl deg/C. We confirmed that almost all the connectors with a return loss of /spl ges/40 dB at 20/spl deg/C had return loss values of /spl ges/35 dB between -40/spl deg/C and 80/spl deg/C.<
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