| 摘要 |
The invention proposes a method and a device in which resonance signals (generated for NMR imaging) are sampled in the presence of a (semi-) static and a time modulated gradient magnetic field, the gradient direction of the fields applied being mutually perpendicular. The resonance signal is conditioned prior to the start of sampling. The sampled signals are associated with spatial frequencies (i.e. points in a spatial frequency space (kx, ky) which is the (2-D) Fourier transform of the actual (x, y) space), which are determined by the applied gradient fields. The (semi-) static gradient field always produces an increase (for example, in kx), while the time modulated gradient field always produces an image frequency which lies between two limits (ky and ky+ky). Consequently, the invention enables the determination of data in an entire band in the (kx, ky) space; this is in contrast with the present state of the art (DE 26.11.497) where data can be collected only along a straight line (kx or ky is constant), or on the entire region of interest (the total kx , ky space). The method and device according to the invention are also applicable for 3-D imaging of 3-D objects. |
