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:
May. 17, 1977
Filed:
Jan. 12, 1976
Applicant:
Inventors:
Philip M Johnson, Windham, NH (US);
Richard M Northrup, Nashua, NH (US);
Assignee:
Sanders Associates, Inc., Nashua, NH (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G01B / ;
U.S. Cl.
CPC ...
356152 ; 33293 ; 356-4 ; 356172 ;
Abstract
A direction finding system is disclosed in which a predetermined horizontal plane is established by the projection from one location of an image having illuminated and unilluminated portions corresponding to the predetermined horizontal plane. A receiver at a remote location detects the image at two spaced points and produces an indication of the center of the transition zone between the illuminated and unilluminated portions of the projected image.