Design of optical-waveguide homogeneous refracting lenses

A class of multielement homogeneous refracting lenses for optical waveguides is presented, and their design procedure is described. These lenses appear to be particularly suitable for use in integrated optical processors, as they can be fabricated by fully planar photolithography and reliable diffusion processes either in glass or in lithium niobate; their optical characteristics can be very good. For example, the design of an f/3.3 waveguide optical system, constituted by five elements, with no field curvature and very well corrected up to a 20 degrees total field of view, is presented.