Abstract:
A micro secondary electron multiplier or an array thereof employs discrete dynodes which are microstructured and applied to an insulating substrate plate. The substrate plate is provided with electrical conductor paths for the connection of the dynodes. The dynodes can be made using a technique such as X-ray depth lithography-galvanoplasty (the LIGA technique). The micro secondary electron multiplier or an array of such multipliers is extremely small and sensitive, and has a high time resolution. Furthermore there is considerable flexibility in positioning the multipliers of an array.
Abstract:
Electron multiplier element for secondary emission, consisting of a first metal plate (11) which has at least one multiplier hole (12) having one input aperture (13) and one output aperture (14), and a second metal plate (16) in parallel with the first plate (11) which has at least one auxiliary hole (17) disposed opposite the output aperture (14) of the multiplier hole (12). The second plate (16) being brought to an electric potential (V1) which is higher than the electric potential (V0) of the first plate. The apertures (13, 14) are such that the projection (18) of the output aperture (14) of the multiplier hole (12) in a plane which is parallel to the first metal plate (11) is at least partially located outside the corresponding projection (19) of the input aperture (13).
Abstract:
The photosensitivity of a photomultiplier dynode to white light or infrared radiation is greatly reduced by coating the dynode with a layer of an alkali halide material having good secondary electron emission characteristics. A method of applying the coating to the dynode is also described.
Abstract:
An ultraviolet sensitive gaseous discharge detector has essentially uniform angular sensitivity in a plane perpendicular to the axis of the detector tube and in the plane of the detector tube axis. The cathode of the detector is in the form of a thin sputtered layer of metal adhering to the inner wall of the envelope of the detector.
Abstract:
A photocathode structure, which can include an alkali halide, has a protective film on an exterior surface of the photocathode structure. The protective film includes ruthenium. This protective film can be, for example, ruthenium or an alloy of ruthenium and platinum. The protective film can have a thickness from 1 nm to 20 nm. The photocathode structure can be used in an electron beam tool like a scanning electron microscope.
Abstract:
The present invention is for a method of preparing a surface of niobium. The preparation method includes polishing, cleaning, baking and irradiating the niobium surface whereby the resulting niobium surface has a high quantum efficiency.
Abstract:
The present invention is for a method of preparing a surface of niobium. The preparation method includes polishing, cleaning, baking and irradiating the niobium surface whereby the resulting niobium surface has a high quantum efficiency.
Abstract:
A photoelectron mask for photo cathode image projection includes a transparent substrate, and a pattern formed on a main surface of the transparent substrate. The pattern includes a non-transparent material. The mask also includes a photoelectron emission film formed so as to cover the main surface of the transparent substrate on which the pattern is formed. The photoelectron emission film includes a material selected from the group consisting of pure platinum, a platinum-rich material containing platinum as the major component, and a platinum compound.
Abstract:
A photoconductive member is provided with increased sensitivity to radiation incident thereupon and with increased photo-yield in response thereto by means of a multi-layered, sandwich-type construction based upon the provision of successive layers of sensitizing material over corresponding successive layers of conducting material. The photoconductive member comprises at least two composite layers formed one above the other on an insulating substrate, each composite layer comprising a first layer of material capable of conducting charge and a second layer of material comprising polar molecules disposed upon the charge-conducting material layer in such a manner that successive layers of polar molecules are adsorbed and retained in an oriented fashion on successive layers of the charge-conducting material. In combination, the alternating layers of charge-conducting material and polar molecules increase photo-yield in response to a given quantum of incident radiation and also increase the range of wavelength of incident radiation to which the photoconductive member is responsive. The sandwich-type construction permits photoconductor sensitivity to be increased as a function of the number of layers of conducting material and polar molecules used to form the photoconductive surface. The multi-layered construction also exhibits reduced sensitivity to the degrading effects of impurities, is adapted to convenient fabrication, and exhibits extended lifetime.