Abstract: Disclosed is a junction device for assembling a PLC (Planar Lightwave Circuit) chip and an optical-fiber block used in an optical-communication system. The junction device includes: an ultraviolet-hardening adhesive filled into a space between the interfaces of the PLC chip and the optical-fiber block, the interfaces being inclined at a given angle; an ultraviolet-light source positioned over the ultraviolet-hardening adhesive for hardening the ultraviolet-hardening adhesive; an optical sensor positioned under the ultraviolet-hardening adhesive for measuring the power changes in the ultraviolet output that have penetrated through the ultraviolet-hardening adhesive; an optical power-meter for displaying the power changes of the ultraviolet based on the data received from the optical sensor; and, a controller for detecting when the ultraviolet-hardening adhesive is completely hardened based on data received from the optical power-meter.

Abstract: A side-chain type second-order nonlinear optical polymer compound having a repeating unit as represented in general structure (I), --(--MO--).sub.m --(--ITCN--NLO--).sub.n --, wherein the sum of m and n is from 5 to 10000 and m and n satisfy m/(m+n)=from 0.05 to 0.95; ITCN--NLO is ##STR1## X is not present, or represents alkylene having from 1 to 6 carbon atoms or aromatic hydrocarbon having from 6 to 12 carbon atoms; Y is a bonding group selected from the group consisting from ether, ester, amide, alkylamino having from 1 to 5 carbon atoms, carbamate and sulfone; NLO is a general second-order nonlinear optical chemical group in which a conjugated aromatic ring can be unsubstituted or substituted by an electron-donor and/or electron-acceptor; and MO is any polymerizable monomer copolymerizable with ITCN--NLO, and a nonlinear optical material prepared with the same arc disclosed.