The cameras of this X-ray detector are all mounted on a common rigid plate by a surface support and screwed to ensure their optical distance from a scintillator itself mounted on the plate by an enclosure forming a darkroom. Among the wide ion beams, at least one wide ion beam has a different dose from that of at least one different wide ion beam. Coupling the optical fibers and the exterior surface of the cable provides unexpected benefits, reducing the tendency of the fiber cable to buckle or shrink-back, and reducing the susceptibility of the cable to fiber retraction. A processor is coupled to the sensor to process the output signals.