INTEGRATED FRESNEL LENS AND METHOD FOR ITS MANUFACTURE

摘要

Fresnel lens for integrated optics, wherein it comprises a light guide of effective index neff incorporating a guiding layer and a number N of regions of length L(r) measured in the direction of the lens axis as a function of the distance r from the lens axis and disposed in the direction perpendicular to the lens axis, while having a refractive index such that to the right of these regions the effective index of the light guide has a value n'eff which differs from neff in such a way that a light wave propagated to the right of these regions is given a phase displacement DELTA phi due to the effective index difference n'eff-neff and making it possible to obtain constructive light interferences at the chosen image point. The invention also relates to a process for producing a Fresnel lens in which the regions are produced by ion implantation.