a method for producing polymeric diacetylene thin films having desirable nonlinear optical characteristics has been achieved by producing amorphous diacetylene polymeric films by simultaneous polymerization of diacetylene monomers in solution and deposition of polymerized diacetylenes on to the surface of a transparent substrate through which ultraviolet light has been transmitted . these amorphous polydiacetylene films produced by photo - deposition from solution possess very high optical quality and exhibit large third - order nonlinear optical susceptibilities , such properties being suitable for nonlinear optical devices such as waveguides and integrated optics .