Abstract: A semiconductor photocathode of the present invention is provided with: a support substrate 10; a photoelectric surface 30 which is formed of a plurality of semiconductor layers layered on this support substrate 10 and which emits photoelectrons from a photoelectron emitting surface 341 in response to the incidence of light to be detected; and a metal electrode 35 which is formed in film form so as to coat at least a portion of support substrate 10 and a portion of photoelectric surface 30 and which makes ohmic contact with the photoelectric surface, wherein metal electrode 30 in film form includes titanium and the electron affinity of photoelectron emitting surface 341, which is an exposed portion of photoelectric surface 30 without being coated with metal electrode 35 in film form, is in a negative condition.

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 prevent the deterioration in sensitivity of the photocathode (20) of an electron tube and maintain stable output for a long time, an ion confining electrode (22) and an ion trap electrode (23) are provided between the photocathode (20) and a first stage dynode (24a). The potential of the ion confining electrode (22) is set higher than that of the first stage dynode (24a), while the potential of the ion trap electrode (23) is set equal to or higher than that of the photocathode (20) and lower than that of the first stage dynode 24a. Since the feedback to the photocathode (20) of the positive ions generated in the vicinity of the first stage dynode can be effectively suppressed, the sensitivity of the photocathode (20) is prevented from decreasing, and stable output is maintained for a long time.

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.

Abstract: An electron tube in which a side tube and a faceplate are sealed together using a malleable metal with a low melting point. The metal is made to spread out along the outer surface of the faceplate due to pressure from a first sealing portion of a sealing metal support member and along the peripheral surface of the electron tube due to pressure from a second sealing portion of the sealing metal support member. Accordingly, the outer side of the corner portion formed by the faceplate and the side tube is covered with the metal. This construction not only reliably secures the input faceplate to the side tube, but also is extremely effective in preserving the airtightness of the electron tube. Since the first sealing portion is pressed toward the faceplate, an appropriate pressure can be applied to the metal interposed between the first sealing portion and the faceplate, improving the sealability of the metal against the faceplate and the first sealing portion.