Deposition of micropatterned coating using an ink-jet technique

Microlenses made of hybrid organic-inorganic materials have been fabricated on glass substrates using a commercial drop-on-demand ink-jet printing system using a 50 mu m diameter nozzle driven by a piezoelectric device. After deposition and evaporation of the solvent, the drops have been polymerized by UV light irradiation. Viscosity, solvent evaporation, drop-substrate wetting condition and drop and substrate temperatures are the main parameters which govern the obtention of reproducible lens shapes. The shape and surface roughness of the lenses have been characterized by atomic force microscopy and profilometry. Their optical properties have been determined by light microscopy and spectrophotometric techniques. The printing technique allows to obtain single and arrays of plano- convex spherical microlenses with diameters varying from 50-300 mu m, focal length from 70 mu m to 3 mm and f-number as low as 0.6. The doping with organic dyes allows to produce colored lenses with similar shapes.