Solution deposited optical waveguide lens

The development of a solution deposited optical waveguide lens, whose focusing effect is produced by an effective index gradient with a hyperbolic secant variation, is described. The lenses are fabricated by a microcontrolled dip coating procedure from colloidal SiO(2):TiO(2) solutions. Both the design and construction of the lens, along with the analytical and experimental results of the focusing properties, are described. The best lenses had speeds of ~f/10 and focal spots ~1.2 times the diffraction limit at apertures of 2.0 mm.