Design, Fabrication and Testing of Kinoform Lenses

INTRODUCTION Fresnel lenses are a type of lens that eliminates the bulk of a conventional lens by collapsing the lens thickness while retaining the curvature necessary for focusing. Figure 1 shows the Fresnel lens equivalent of a conventional lens. For a rotationally symmetric lens, the discontinuities or grooves formed when collapsing the lens are annular. This produces a much thinner lens, particularly for large apertures.