Design of photoinduced relief optical devices with hybrid sol-gel materials

Photosensitive organic-inorganic compounds appear as an alternative option for the design of new optical devices since they combine the characteristics of both glasses and photopolymers and improve the properties of the final material. These hybrid materials consisted of methacryloxypropyltrimethoxysilane, titanium isopropoxide, methacrylic acid and a photoinitiator. The hybrid sol-gel film was obtained via hydrolysis-condensation reactions and coating on a substrate. Spatially controlled UV irradiation induced the polymerization of the organic parts 1, thus, leading to structural changes and relief generation. Due to the characteristics of the sensitive material, no further etching is required to reveal the surface corrugation. These new innovative advanced materials, open up new vistas in the field of optical devices. Hybrid classes, in which the organic and inorganic phases are blended at the sub-micrometric scale, are transparent and with low optical loss. In addition, they are harder than organic polymers but less brittle than silica. Hybrid sol-gel glasses generated by this self-developing process are shown to be suitable for generation of optical components such as diffraction gratings. (C) 2002 Elsevier Science B.V. All rights reserved.