Abstract: A neutron imaging system includes a neutron generator, a flight tube, a stage, a neutron imaging module, and a neutron shield. The flight tube enables neutrons from the neutron generator to enter the flight tube through an input opening and exit through an output opening. The stage supports a sample object to receive neutrons that pass through the entire length of the flight tube and the output opening. The neutron imaging module has a neutron-sensitive component that receives neutrons that pass through the sample object and generates neutron detection signals. The neutron shield surrounds at least a portion of the flight tube and the neutron imaging module to block at least a portion of stray neutrons that travel toward the neutron-sensitive component of the neutron imaging module, in which the stray neutrons do not enter the flight tube through the input opening of the flight tube.

Abstract: A neutron imaging system includes a neutron generator, a flight tube, a stage, a neutron imaging module, and a neutron shield. The flight tube enables neutrons from the neutron generator to enter the flight tube through an input opening and exit through an output opening. The stage supports a sample object to receive neutrons that pass through the entire length of the flight tube and the output opening. The neutron imaging module has a neutron-sensitive component that receives neutrons that pass through the sample object and generates neutron detection signals. The neutron shield surrounds at least a portion of the flight tube and the neutron imaging module to block at least a portion of stray neutrons that travel toward the neutron-sensitive component of the neutron imaging module, in which the stray neutrons do not enter the flight tube through the input opening of the flight tube.

Abstract: A channel electron multiplier having a high aspect ratio and differential coatings along its channel length is disclosed. The elongated tube has an input end, an output end, and an interior surface extending along the length of the tube between the input end and the output end. The channel electron multiplier also has first and second conductive layers formed on the interior surface of the tube. The first conductive layer is selected to provide a first electrical resistance, a first electron emission characteristic, or both, and the second conductive layer is selected to provide a second electrical resistance, a second electron emission characteristic, or both. A method of making a channel electron multiplier having two or more different conductive layers is also disclosed.