For the purpose of better exploitation of the 35 mm film format, it is typical to record a horizontally compressed image (using an anamorphic imaging objective) to fill the format on the 35 mm film. When playing back the film, an anamorphic imaging objective is again needed, which images the recorded film using different enlargements in the two main sectional planes, so that the film is shown undistorted in the wide format on the motion picture screen.
Anamorphic imaging objectives are also used in the post-processing of motion pictures. For this purpose, the filmstrips of the original recording, the so-called master, is recopied onto another film while simultaneously performing certain filter operations. During this recopying procedure, for example, the aspect ratio of the original film recording may subsequently be changed using an anamorphic imaging objective.
Anamorphic imaging objectives in which cylindrical and toric lenses are used in one or more groups to achieve the anamorphic effect are known. In particular, a rotationally-symmetric main objective is frequently combined with one or more anamorphically effective auxiliary elements. However, all of these solutions have imaging errors in undesired amounts and lead to unsatisfactory results.
USPTO Backgrounds
USPTO Backgrounds