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. 14, 1993
Filed:
Aug. 05, 1992
Stefan Nowak, Braeuningshof/Erlangen, DE;
Franz Schmitt, Erlangen, DE;
Siemens Aktiengesellschaft, Munich, US;
Abstract
A nuclear magnetic resonance tomography apparatus has at least one gradient coil interconnected with a capacitor to form a resonant circuit. Before the beginning of each read-out sequence, the capacitor is charged to a higher voltage than would be necessary to produce a pure sine oscillation during the read-out sequence. The rise time of the gradient pulse thus produced is less than one-fourth of the duration of the sinusoidal oscillation before the zero-axis crossing, and the decay time is less than one-fourth of the duration of the sinusoidal oscillation after the zero-axis crossing. Additionally, a constant part of each gradient pulse is non-resonantly generated by a gradient amplifier. Only the steep parts of the oscillation of the resonant circuit are used for the rising and trailing edges, whereas the flattened part of the sine oscillation is cut off. The rising and trailing edges can thus be noticeably shortened, so that a greater range for the constant gradient value, which can be equidistantly sampled in the k-space is available for the signal evaluation.