Abstract:
In the polycrystal diamond thin film in accordance with the present invention, the average particle size is at least 1.5 nullm and, in a Raman spectrum obtained by Raman spectroscopy, a peak intensity near a wave number of 1580 cmnull1 has a ratio of 0.2 or less with respect to a peak intensity near a wave number of 1335 cmnull1. The photocathode and electron tube in accordance with the present invention comprise the polycrystal diamond thin film as a light-absorbing layer.
Abstract:
A photocathode structure having a photoelectric face plate protective layer, in order to prevent a photoelectric effect from being deteriorated sharply due to a high reaction of oxygen with respect to most of existing photoelectric face plate materials when the photoelectric face plate used for generating photoelectrons by a photoelectric effect i s exposed to the atmosphere, is provided. For example, a diamond-like carbon thin layer is used as a photocathode protective layer, to thereby perform a function of protection of the photoelectric face plate through isolation of the photoelectric face plate from the atmosphere and enable electrons generated from the photoelectric face plate to pass through a diamond-like carbon thin layer, which is deposited thinly, by the tunneling effect so that the performance of the photocathode is not affected. By using the protective layer, the processes subsequent to the photoelectric face plate deposition process can be freely performed in the atmosphere, to thereby simplify the whole process. As a result, a production cost is lowered, and manufacturing of a device or apparatus using a large-are photocathode is facilitated.
Abstract:
A device for monitoring radiation flux from a surface. The flux monitor is based on the photoelectric effect that occurs inherently when a reflective metal optic is exposed to a beam of energetic radiation. The incoming beam of energetic radiation is not totally reflected by the optic surface. That portion of the radiation absorbed by the optic generates photoelectrons producing a signal proportional to the incident radiation flux. By measuring this signal, an accurate determination of the radiation reflected by the optic surface can be made.
Abstract:
A cathode (5) for emitting photoelectrons or secondary electrons comprises a nickel electrode substrate (5c) with an aluminum layer (5b) deposited on it; an intermediate layer (5a) consisting of carbon nanotubes formed on the aluminum layer; and an alkaline metal layer (5d) formed on the intermediate layer (5a) and composed, for example, of particles of an alkali antimony compound that either emits photoelectrons in response to incident light or emits secondary electrons in response to incident electrons. The decrease in defect density of the particles reduces the probability of recombination of electron and hole remarkably, thus increasing quantum efficiency.
Abstract:
The present invention relates to an apparatus (11) for conversion of visible light to UV light, and includes an entrance window (17) transparent to visible light; a photocathode (23) adapted to release photoelectrons in dependence on being irradiated by visible light; an electrode arrangement (27, 29) connectable to a voltage supply; a scintillator (21, 35) adapted to emit UV light in dependence on being struck by electrons; and an exit window (19) transparent to UV light. Visible light is, during conversion, entered through the entrance window and irradiates the photocathode. Photoelectrons released from the photocathode is, by means of an electrical field created by the electrode arrangement, drifted towards the scintillator, where they are converted into scintillating light, which is output through the exit window. The converter is advantageously arranged in front of a gaseous based two-dimensional UV light detector for detection of visible light.
Abstract:
A vacuum casing for a vacuum tube has an X-ray window which is formed of vitreous carbon and is joined to the vacuum enclosure by an active brazing alloy.
Abstract:
An image intensifier tube includes a photocathode (20) with an active layer (52) providing an electrical spectral response to photons of light. The photocathode (20) also includes integral spacer structure (42) which extends toward and physically touches a microchannel plate (22) of the image intensifier tube in order to establish and maintain a desirably precise and fine-dimension spacing distance nullGnull between the photocathode and the microchannel plate. A method of making the photocathode and a method of making the image intensifier tube are described also.
Abstract:
An electron beam source has a photocathode with a photoemitter material having a work function, and with a beam receiving portion and an electron emitting portion. A first light source directs a first light beam onto the beam receiving portion of the photocathode to generate an electron beam from the electron emitting portion. The first light beam has a wavelength null1 such that hc/null1 is at least about the work function of the photoemitter material, where nullhnull is Planck's constant and nullcnull is the speed of light. A second light source directs a second light beam onto the beam receiving portion of the photocathode, such as onto the beam receiving portion, to stabilize the electron beam. The second light beam having a wavelength null2 such that hc/null2 is less than about the work function of the photoemitter material.
Abstract:
Ultraviolet light incident from the side of a surface layer 5 passes through the surface layer 5 to reach an optical absorption layer 4. Light which reaches the optical absorption layer 4 is absorbed within the optical absorption layer 4, and photoelectrons are generated within the optical absorption layer 4. Photoelectrons diffuse within the optical absorption layer 4, and reach the interface between the optical absorption layer 4 and the surface layer 5. Because the energy band is curved in the vicinity of the interface between the optical absorption layer 4 and surface layer 5, the energy of the photoelectrons is larger than the electron affinity in the surface layer 5, and so photoelectrons are easily ejected to the outside. Here, the optical absorption layer 4 is formed from an Al0.3Ga0.7N layer with an Mg content concentration of not less than 2null1019 cmnull3 but not more than 1null1020 cmnull3, so that a solar-blind type semiconductor photocathode 1 with high quantum efficiency is obtained.
Abstract translation:从表面层5侧入射的紫外线通过表层5到达光吸收层4.到达光吸收层4的光被吸收在光吸收层4内,光吸收在光吸收 光电子在光吸收层4内扩散,并到达光吸收层4和表面层5之间的界面。因为能带在光吸收层4和表面层5之间的界面附近弯曲 ,光电子的能量大于表面层5中的电子亲和力,因此光电子容易被排出到外部。 这里,光吸收层4由Mg含量浓度不小于2×10 19 cm -3但不大于1×10 20 cm -3的Al 0.3 Ga 0.7 N层形成,因此 得到具有高量子效率的太阳能型半导体光电阴极1。
Abstract:
A photocathode and an electron tube in which the photocathode plate can be securely fixed without using any adhesive. Even under the severe condition that a high vibration resistance is required or thermal stress occurs because of great temperature variation, it can be used widely for an image intensifier, a streak tube, or a photomultiplier. The photocathode plate of the photocathode is sandwiched between a faceplate and a support plate. First pins embedded in the faceplate are joined to the support plate. Therefore, the photocathode plate can be readily fixed securely to the faceplate without using any adhesive.