On May 03, 2016 , the USPTO issued U.S. Patent Number 9,329,285 to RAPISCAN SYSTEMS, INC., which was successfully prosecuted by Novel IP.
The '285 patent is directed towards 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 combination photon and neutron detector comprising a first layer comprising a scintillator; a second layer positioned below the first layer, said second layer comprising boron and configured to captured neutrons; a third layer positioned below the second layer, said third layer comprising boron and configured to capture neutrons; and a gas layer, positioned between the second and third layer, wherein, when a neutron is captured, the second and third layers emit charged particles that ionize gas in the gas layer creating free electron and ion pairs. "