The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 27, 1976
Filed:
Oct. 24, 1974
Ernst Leitz G.m.b.H., Wetzlar, DT;
Abstract
In an apparatus, an imaging system, at least one optically effective grating and a photoelectric receiver system are employed for determining the relative position of the plane of maximum amplitude of a spatial frequency component in the image of an object. The imaging system produces from light fluxes emanating from the object and traversing different regions of the entrance pupil of the imaging system an image of the object in a first, a second and a third intermediate image plane. The focussing screen mounted in the first plane is used for subjectively observing and focussing the object as well as for transmitting light fluxes to the optically effective grating which defines a given spatial frequency component and which is mounted at least in the vicinity of the second intermediate image plane for commonly modulating and splitting the light fluxes. The photoelectric receiver system generates therefrom electrical output signals used in devices for indicating and adjusting the sharp focussing of the object.