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:
Nov. 22, 1983
Filed:
May. 19, 1981
Godfrey N Hounsfield, Newark, GB;
Picker International Limited, Wembley, GB;
Abstract
In NMR imaging systems a pulsed field gradient may be applied across an excited slice (1) and the resonance signal detected during the field gradient pulse. It has been usual to demodulate the resonance signal at the Larmor frequency for a strip at the center of the slice, at which generally the field gradient has a zero-crossing. It has, however, been proposed to put the zero-crossing outside the slice, still demodulating at the slice Larmor frequency. In this invention demodulation is actually at the frequency for a probe (12) which is necessarily outside the patient. This makes the demodulation independent of errors in a local oscillator frequency. Demodulation may be for a probe effect to give a frequency for a strip outside the slice or the probe may be perpendicular to the gradient to give the zero-crossing frequency.