Non linear optical material and method for orientation thereof

An optical modulation system comprising:

• a laser, and
• an optical modulator including a film of a nonlinear optical material and an electrode disposed on said film, said nonlinear optical material, comprising:
• a solid solution of from 5-80 parts by weight of a centrosymmetric para-disubstituted organic guest compound showing no second harmonic generation (SHG) by itself and having a molecular dipole moment in 100 parts by weight of polyoxyalkylene matrix, wherein the polyoxyalkylene matrix comprises oxyalkylene units of the formula (1) below at least as a partial structure including two or more successive oxyalkylene units in a proportion of 30 mol % or more in the polyoxyalkylene,
• Formula (1):
• (R--O).sub.n,
• wherein R denotes an alkylene group containing 1-6 carbon atoms, and n is 2-200,000;
• and the organic guest compound comprises a para-disubstituted benzene ring to which an electron donative group and an electron attractive group are attached to provide the molecular dipole moment,
• wherein said electron donative group is an amino group, alkyl group, alkoxy group, alkylamino group, hydroxyalkylamino group, dialkylamino group, hydroxyalkyl-alkylamino group, dihydroxyalkylamino group, mercapto group, or hydroxy group;
• and said electron attractive group is a nitro group, cyano group, halogen atom, trifluoromethyl group, carboxyl group, carboxy ester group, carbonyl group or sulfonyl group.