Showing papers on "Apochromat published in 1979"
TL;DR: Two types of compensation gratings are studied: point holograms reconstructed out of stigmatic conditions and holograms of the aberrating wave surface itself, reconstructed in the conjugate order.
Abstract: Chromatic and spherical aberration of Fresnel-zoned diffraction gratings may be of the opposite sign and the same magnitude as for glass lenses. This peculiarity is used to improve the stigmatism of single glass lenses in polychromatic radiation. Two types of compensation gratings are studied: point holograms reconstructed out of stigmatic conditions and holograms of the aberrating wave surface itself, reconstructed in the conjugate order.
29 citations
Patent•
29 May 1979
TL;DR: In this paper, a variable meniscus-shaped air space and cementing surface which are respectively concave and concave against a stop provided therein is provided for a variable aberration lens system.
Abstract: A variable aberration lens system usable not only as a general photographic lens but also a soft focus lens is provided. The variable aberration lens system includes at least a variable meniscus-shaped air space and cementing surface which are respectively concave against a stop provided therein. A very high resolving power and high contrast can be obtained when the variable aberration lens system is used as the general photographic lens, and a photograph in which an out focus image of the background or foreground is fine can be obtained by varying the width of the air space when the variable aberration lens system is used as the soft focus lens.
3 citations