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. 23, 2000
Filed:
Nov. 19, 1997
Marcus T Alley, Palo Alto, CA (US);
Norbert J Pelc, Los Altos, CA (US);
The Board of Trustees of the Leland Stanford Junior University, Palo Alto, CA (US);
Abstract
Disclosed is a method for characterizing the gradient subsystem of a Magnetic Resonance (MR) system. The method uses a Fourier-transform analysis to directly measure the k-space trajectory produced by an arbitrary gradient waveform. In addition, the method can be easily extended to multiple dimensions, and can be adapted to measuring residual gradient effects such as eddy currents. Several examples of gradient waveform and eddy-current measurements are presented. Also, it is demonstrated how the eddy-current measurements are presented. Also, it is demonstrated how the eddy-current measurements can be parameterized with an impulse-response formalism for later use in system tuning. When compared to a peak-fitting analysis, this technique provides a more direct extraction of the k-space measurements, which reduces the possibility of analysis error. This approach also has several advantages as compared to the conventional eddy-current measurement technique, including the ability to measure very short time constant effects.