Fabrication of microlenses by laser-induced vaporization

Three-dimensional microlenses were fabricated on a quartz substrate by evaporating a quartz target with a focused CO(2) laser beam. The size and shape of the deposit were determined primarily by a mask placed in front of the substrate. The spherical thickness profile required for a lens was obtained by adjusting the gas pressure in the cell. The lens was typically 0.25 mm in diameter with a focal length of 8 mm. The present method is particularly suited for fabrication of microlens arrays, and as a demonstration a 3 x 5 array was produced.