Mechanics of tunable hemispherical electronic eye camera systems that combine rigid device elements with soft elastomers

A tunable hemispherical imaging system with zoom capability was recently developed by exploiting heterogeneous integration of rigid silicon photodetectors on soft, elastomeric supports, in designs that can facilitate tunable curvature for both the lens and detector. This paper reports analytical mechanics models for the soft materials aspects of the tunable lenses and detector surfaces used in such devices. The results provide analytical expressions for the strain distributions, apex heights and detector positions, and have been validated by the experiments and finite element analysis. More broadly, they represent important design tools for advanced cameras that combine hard and soft materials into nonplanar layouts with adjustable geometries.