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:
Sep. 01, 1992
Filed:
Sep. 18, 1990
Helmut Kess, Erlangen, DE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
A transmission antenna for a nuclear magnetic resonance apparatus has a capacitor connected in parallel with it via at least one PIN diode, and a reception antenna for the apparatus has a capacitor connected directly in parallel with it and an inductor connected in parallel with it via a PIN diode. The PIN diodes are connected to a control voltage in a series circuit. Given a first direction of the control voltage, the PIN diodes are conductive, so that the transmission antenna is tuned to the nuclear magnetic resonant frequency due to cut-in of the capacitor and the reception antenna is detuned to the cut-in of the inductor. Given a second direction of the control voltage, the reception antenna is tuned to the nuclear magnetic resonant frequency and the transmission antenna is detuned with respect to the nuclear magnetic resonant frequency. An unwanted, local super-elevation of the RF power cannot occur with this antenna.