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:
Dec. 06, 1983
Filed:
Feb. 17, 1981
William R Guth, Hoffman Estates, IL (US);
Siemens Gammasonics, Inc., Des Plaines, IL (US);
Abstract
A test pattern device for testing scintillation cameras has a radiation transparent body member with internal mercury-filled communicating passages that define a calibrated radiation opaque test pattern. A peripheral passage serves as a mask to outline the useful field of view of the camera crystal, and expansion chambers accommodate changes in mercury volume due to temperature. The body member is made by securing a plastic cover plate to a plastic base molded with grooves to form the test pattern passages and filling ports, and then sealing the filling ports after mercury has been added to fill the passages. The invention avoids the tolerance problems associated with the manufacture of conventional lead test pattern devices.