Arrays of microlenses of complex shapes prepared by reaction-diffusion in thin films of ionically doped gels

This letter describes a wet-stamping technique for the fabrication of highly regular arrays of microlenses through reaction-diffusion-swelling processes occurring in a thin film of ionically doped gelatin. Geometrical parameters of the lenses depend on and can be controlled by the geometries of the stamped features and the concentrations of chemicals diffusing and reacting in the gelatin matrix. Surface topographies of the lenses are studied experimentally, and are reproduced by a lattice gas reaction-diffusion model. (C) 2004 American Institute of Physics.