On March 31, 2015 , the USPTO issued U.S. Patent Number 8993970 to RAPISCAN SYSTEMS, INC., which was successfully prosecuted by Novel IP.
The '970 patent is directed towards a invention which provides a switchable photomultiplier switchable between a detecting state and a non-detecting state including a cathode upon which incident radiation is arranged to impinge. The photomultiplier also includes a series of dynodes arranged to amplify a current created at the cathode upon detection of photoradiation. The invention also provides a detection system arranged to detect radiation-emitting material in an object. The system includes a detector switchable between a detecting state in which the detector is arranged to detect radiation and a non-detecting state in which the detector is arranged to not detect radiation. The system further includes a controller arranged to control switching of the detector between the states such that the detector is switched to the non-detecting state while an external radiation source is irradiating the object.
Independent Claim 1 describes "An inspection system for scanning an object for threat materials comprising: a plurality of passive detectors configured to detect passive radiation emitted from material in the scanned object; an active detection system comprising a radiation source to irradiate the scanned object and a plurality of active detectors configured to detect radiation emitted by said radiation source after it passes through and/or is scattered by the scanned object; and a control system configured to perform the functions of controlling a switching of passive detectors between a detecting state and a non-detecting state such that the passive detectors are switched to a non-detecting state when the active radiation source is irradiating the object; receiving separate sets of detection data from the plurality of passive and active detectors; and correlating said separate sets of detection data to estimate a presence of threat materials in the scanned object".