Patent ID: 6777937
Filing Date: 2004-08-17
Classification: G01R

Abstract:
An NQR apparatus for irradiating a sample with an RF magnetic field and for determining the presence of a target material by detecting an NQR signal, comprising:a transmitter for generating an output signal at a selected frequency; a receiver for detecting the NQR signal; a probe; a switch coupling said receiver and said transmitter with said probe for alternately connecting and disconnecting said receiver and said transmitter to said probe, thereby switching said NQR apparatus between a transmitting mode and a receiving mode; wherein said probe comprises a resonant circuit including a coil array, and wherein said coil array comprises a first figure-8 coil and a partially overlapping, second figure-8 coil for generating an RF magnetic field in a detecting region outside said probe, and wherein said first and second coil are configured for alternating together between a transmitting mode for irradiating a sample in the detecting region with an RF magnetic field, and a receiving mode for detecting the NQR signal indicative of the presence of a target material in the sample.