SUPERRESOLUTION PERFORMANCE OF AN ABSORBING GLASS POSITIVE LENS ELEMENT

Superresolution performance of a piano-convex lens made of absorbing g lass is analyzed numerically. It was found that a reduction of the rad ius of the Airy disk depends solely on the center transmittance of the lens (a zero edge thickness is assumed) for any reasonable ratio of r adius of curvature of the convex surface and the lens radius. The mode st decrease in the size of the central diffraction peak is followed by a large decrease of its energy content and a rapid brightening of the diffraction rings. The most that can be achieved with such a lens is a reduction of the radius of the Airy disk to 71% of the corresponding clear aperture value, followed by approximately 78% of the energy bei ng diverted into diffraction rings. (C) 1997 Optical Society of Americ a.