Photosensors, namely, light sensors, and replacement parts and structural parts therefor; Detectors, namely, detector machines for use in detecting ion, x-rays, ultraviolet rays, electron radiation, and other atomic and subatomic particles, and replacement parts and structural parts therefor; Detection elements, namely, ion detection elements in the nature of ion detectors consisting of electron multipliers and avalanche photodiodes for use in detecting ion, x-rays, ultraviolet rays, electron...