Abstract: In an electron beam detector, a light guide optically couples a fluorescence emitting surface of the compound semiconductor substrate to a light incident surface of the photodetector, and physically connects the compound semiconductor substrate with the photodetector, thereby integrating the compound semiconductor substrate with the photodetector. When the compound semiconductor substrate converts incident electrons to fluorescent light, the light guide guides the fluorescent light to the photodetector, and the photodetector detects the fluorescent light, thereby detecting the incident electrons.

Abstract: In an electron beam detector, a light guide optically couples a fluorescence emitting surface of the compound semiconductor substrate to a light incident surface of the photodetector, and physically connects the compound semiconductor substrate with the photodetector, thereby integrating the compound semiconductor substrate with the photodetector. When the compound semiconductor substrate converts incident electrons to fluorescent light, the light guide guides the fluorescent light to the photodetector, and the photodetector detects the fluorescent light, thereby detecting the incident electrons.

Abstract: To provide an electron tube having good airtightness and being appropriate for mass production, indium affixed to the inner surface of a sealing metal support member is provided between a side tube and input faceplate. The input faceplate is pushed against the side tube. As a result, the indium is squeezed by a pressure receiving surface provided on the end face of the side tube. Since the pressure receiving surface is in a generally declining shape from the inside out, the force of the pressing surface causes the indium to flow outward toward the sealing metal support member. Therefore, the indium is firmly affixed to the pressure receiving surface, and the side tube and input faceplate can be reliably sealed by the indium.