A method for compensation of field inhomogeneities of the first order with the core pin tomography devices

摘要

The method involves injecting a first HF pulse (RF1) which stimulates a vol. in an investigation vol. extending in a first direction. A gradient echo signal is produced by injecting a gradient pulse (G1) in the first direction and reversing it. A second HF pulse stimulates a vol. in the first direction and a second gradient echo signal is also produced. An offset current is detected from the difference in the time intervals between the first and second Hf and gradient echo pulse pairs. This current is applied to the gradient coils in subsequent measurement sequences to null the time interval difference. ADVANTAGE - Correction of first order magnetic field errors is achieved using simple method.