Neutron imaging system having neutron shield

A neutron imaging system comprising:

• a neutron generator that is configured to produce neutrons from a nuclear fusion reaction;
• a shielded flight tube that has an input opening, an output opening, a flight tube wall extending from the input opening to the output opening, and a flight tube shield surrounding the flight tube wall, in which the flight tube is positioned relative to the neutron generator to enable neutrons from the neutron generator to enter the flight tube through the input opening and exit the flight tube through the output opening, and the flight tube shield is configured to substantially block neutrons outside of the flight tube from entering the flight tube through the flight tube wall;
• a sample chamber configured to support a sample object at a position to receive neutrons that pass through the output opening of the flight tube;
• and
• a shielded neutron detector comprising a microchannel plate detector and a detector shield, in which the microchannel plate detector includes an input electrode, an output electrode, and a microchannel plate defining microscopic channels, the input electrode is configured to be connected to a first voltage, the output electrode is configured to be connected to a second voltage different from the first voltage, the neutron detector is configured receive at least a portion of the neutrons that pass through the sample object and generate output signals upon detection of the neutrons, and the detector shield is configured to substantially block neutrons other than those that have traveled the entire length of flight tube and pass through the output opening of the flight tube from reaching the neutron detector.