Abstract:
The invention provides a switchable photomultiplier switchable between a detecting state and a non-detecting state comprising a cathode upon which incident radiation is arranged to impinge. The photomultiplier also comprises a series of dynodes arranged to amplify a current created at the cathode upon detection of photoradiation. A first dynode of the series is operatively closest to the cathode and is at a first potential and the electrical potential of the cathode is switchable between a second potential, below the first potential, when the photomultiplier is in the detecting state and a third potential, above the second potential, when the photomultiplier is in the non-detecting state. The invention also provides a detection system arranged to detect radiation-emitting material in an object. The system comprises a detector switchable between a detecting state in which the detector is arranged to detect radiation and a non-detecting state in which the detector is arranged to not detect radiation. The system further comprises a controller arranged to control switching of the detector between the states such that the detector is switched to the non-detecting state whilst an external radiation source is irradiating the object.
Abstract translation:用于检测紫外线的光电倍增管,其中以高精度调节太阳盲特性。 光电倍增管包括具有用于吸收光的窗口部件的气密密封容器,并且包括光电阴极和多级二极管的电子倍增部分并且在光电阴极上对光电子进行级联倍增设置在密封容器中 。 光电阴极包含Al X 1 Ga 1-X N(0 = X 1)。 在二极管的多个阶段中,包括从光电阴极接收光电子的第一级二极管的至少两个连续阶段分别由铍铜合金基板构成,并且在其上形成包含氧化铍的二次电子发射表面 设置在每个铍铜合金基板中的多个二次电子倍增孔的内壁。
Abstract:
A photomultiplier having a structure for easily realizing high detection accuracy and microfabrication and its manufacturing method are disclosed. The photomultiplier (1a) comprises an enclosure (2, 3, 4) the inside of which is maintained in a vacuum state. In the enclosure (2, 3, 4), a photoelectric surface (22) for emitting electrons in response to the incident light, an electron multiplying section (31) for cascade-multiplying electrons emitted from the photoelectric surface (22), and an anode (32) for extracting secondary electrons produced by the electron multiplying section (31) are provided. A part of the enclosure (2, 3, 4) is composed of glass substrates (20, 40) each having a flat portion. On the flat portions of the glass substrates (20, 40), the electron multiplying section (31) and the anode (32) are two-dimensionally arranged, respectively.
Abstract:
A photomultiplier tube includes: a cathode (3) for emitting electrons by the incident light; a plurality of stages of dynode (107) for multiplying the electrons emitted from the cathode (3); and an electronic lens formation electrode (115) arranged at a predetermined position with respect to the edge of a first dynode (107a) located at the first stage from the cathode (3) and the edge of the second dynode (107b) located at the second stage from the cathode (3) and flattening the equipotential surface in the space between the first dynode (107a) and the second dynode (107b) in the longitudinal direction of the first dynode (107a). With this configuration, it is possible to improve the time resolution for the incident light.
Abstract:
A photomultiplier tube includes a semiconductor photocathode and a photodiode. Notably, the photodiode includes a p-doped semiconductor layer, an n-doped semiconductor layer formed on a first surface of the p-doped semiconductor layer to form a diode, and a pure boron layer formed on a second surface of the p-doped semiconductor layer. A gap between the semiconductor photocathode and the photodiode may be less than about 1 mm or less than about 500 µm. The semiconductor photocathode may include gallium nitride, e.g. one or more p-doped gallium nitride layers. In other embodiments, the semiconductor photocathode may include silicon. This semiconductor photocathode can further include a pure boron coating on at least one surface.
Abstract:
A photomultiplier having a fine structure for realizing high multiplication efficiency. The photomultiplier comprises an enclosure the inside of which is maintained in a vacuum state. In the enclosure, a photoelectric surface for emitting photoelectrons in response to the incident light, an electron multiplying section for cascade-multiplying photoelectrons emitted from the photoelectric surface, and an anode for extracting secondary electrons produced by the electron multiplying section are provided. Especially a groove section for cascade-multiplying the photoelectrons from the photoelectric surface is formed in the electron multiplying section. On the surfaces of a pair of wall portions (311) defining the groove section, one or more projecting portions (311a) having secondary electron emitting surface are provided.
Abstract:
A polycrystalline diamond thin film which has an average particle size of at least 1.5 mu m and a peak intensity in the vicinity of wavelength of 1580 cm in a Raman spectrum obtained by a Raman spectroscopy having a ratio of up to 0.2 with respect to a peak intensity in the vicinity of wave number of 1335 cm . A photocathode (2) and an electron tube (1) are each provided with the above polycrystalline diamond thin film as a light absorbing layer (22).