A microcylindrical lens array made of silver-halide-sensitized gelatin etched by an enzyme with a real-time mask

Abstract

A novel method has been developed to fabricate microcylindrical lenses by etching silver-halide-sensitized gelatin (SHSG) with an enzyme solution, and the exposure pattern is produced on SHSG through a real-time mask technique. In this paper the principle of etching SHSG with an enzyme solution is given in detail and the optimum technique parameters of this process are presented; furthermore the theoretical analysis and solving scheme for the nonlinearities which arise from the absorption of light energy by film are given. A good linear relationship is experimentally obtained between the etching depth and time in depth a range up to 4 μm. Finally, the microcylindrical lens is achieved by experiment. The results are evaluated for experiments with a stylus profiling instrument and scanning electron microscope. This method does not require the use of expensive equipment, and it is not sophisticated and time consuming. So it is a practical method to fabricate excellent micro-optical elements.