On February 24, 2015 , the USPTO issued U.S. Patent Number 8963094 to RAPISCAN SYSTEMS, INC., which was successfully prosecuted by Novel IP.
The '094 patent is directed towards present invention which provides a gamma-neutron detector based on mixtures of thermal neutron absorbers that produce heavy-particle emission following thermal capture. In one configuration, B-10 based detector is used in a parallel electrode plate geometry that integrates neutron moderating sheets, such as polyethylene, on the back of the electrode plates to thermalize the neutrons and then detect them with high efficiency. The moderator can also be replaced with plastic scintillator sheets viewed with a large area photomultiplier tube to detect gamma-rays as well. The detector can be used in several scanning configurations including portal, drive-through, drive-by, handheld and backpack, etc.
Independent Claim 1 describes " a gamma-neutron detector, comprising: a first layer of neutron sensitive composite scintillator; and a second and a third layer of gamma sensitive scintillators, wherein the first layer is positioned between the second and third layers and wherein the second and third layers comprise plastic scintillators with a fast decay time and the first layer comprises scintillators with a slower decay time".