Abstract:
Electron multipliers, radiation detectors, and methods of making the multipliers and detectors are described. In some embodiments an electron multiplier has a structure including a plurality of interconnected fibers having electron-emissive surfaces, the fibers having a width to thickness aspect ratio greater than one.
Abstract:
To reduce the size of a photomultiplier tube (1), a side tube (2) is fixedly secured by welding to a stem plate (4) while an inner surface (2c) of the lower portion (2a) of the side tube (2) is maintained to be in contact with an outer edge (4b) of the stem plate (4). As a result, there is no projection like a flange at the lower portion of the photomultiplier tube (1). Therefore, though it is difficult to perform resistance welding, the outside dimensions of the photomultiplier tube (1) can be decreased, and the side tubes (9) can densely abut to one another even if the photomultiplier tubes (2) are arranged when applied. Hence, high-density arrangement of photomultiplier tubes (1) are realized by assembling metallic stem plate (4) and the side tube (2) by, for example, laser welding.
Abstract:
A photomultiplier tube includes dynodes electrically joined to corresponding leads. The tube, containing a loose debris particle, may be reprocessed by positioning the particle at an accessible site inside the tube. A power laser is aimed at the particle through a transparent wall of the tube and fired to reduce the size of the particle.
Abstract:
This invention relates to an electron tube having a structure for enabling a stable operation for a long time. In the electron tube, at least a confining mechanism is arranged between a photocathode and the electron incident surface of a semiconductor device, which are arranged to oppose each other. In the arrangement, the area of the opening of the confining mechanism is at least equal to or smaller than that of the electron incident surface, thereby confining the orbits of photoelectrons from the photocathode. This structure avoids bombardment of electrons arriving at portions other than the electron incident surface of the semiconductor device and prevents the semiconductor device from being unnecessarily charged.
Abstract:
A photomultiplier tube is disclosed having a first dynode array and a second dynode array oriented substantially orthogonal to the first dynode to provide a shortened profile. The first dynode array is preferably a box-and-grid dynode array and the second dynode array is preferably an in-line dynode array. A focusing electrode is positioned between the last dynode of the first dynode array and the first dynode of the second dynode array. The focusing electrode is constructed and arranged to facilitate the transfer of electrons emitted from the first dynode array to the second dynode array without generating secondary electrons.
Abstract:
A photomultiplier includes a cascade of microchannel plates which are physically and electrically connected to provide an electron multiplication through the microchannel cascade. One of the microchannel plates is a high-output microchannel plate providing a high level of electron multiplication. This high output microchannel plate is thermally conducted to ambient by a heat transfer path including outwardly disposed microchannel plates in the cascade. A unitary ceramic housing defines a vacuum envelope for the photomultiplier.
Abstract:
The present invention relates to a multiplier structure having a very compact shape and which can have the output electrodes of the channels arranged in any random direction. The multiplying structure (94) is a ceramic block obtained by baking a stack of ceramic sheets prepared beforehand with a view to forming cavities includes in the mass. Each cavity (21) is covered by a metal deposit connected to a lateral contact (23) by a conductor (24) printed beforehand on the corresponding sheet. The channels can have special geometries in order to have their output on several different surfaces (41, 46, 47) of the multiplying structure.
Abstract:
A channel electron multiplier phototube having a channel electron multiplier, a transparent faceplate, and an anode assembly. The channel electron multiplier includes an insulating body having a curved passageway extending therethrough. A photoemissive element, and a secondary emissive dynode material is on the walls of the passageway. The passageway, together with a photoemission film of the photocathode assembly and the anode of the anode assembly define an evacuated closed region. Preferably, the electron multiplier is a monolithic ceramic body.
Abstract:
A so-called "solar-blind" photomultiplier tube includes an envelope having a sidewall and an input faceplate formed from an ultraviolet transmitting filter. A photoemissive cathode is disposed within the envelope for providing photoelectrons in response to radiation incident thereon. The cathode has an intrinsic responsivity extending from the near-ultraviolet portion through the visible portion of the electromagnetic spectrum; however, the filter faceplate transmits only the ultraviolet portion of the spectrum to the photoemissive cathode. The combination of the filter faceplate and the photoemissive cathode therefore limits the tube to a responsivity within the wavelength range of about 300 to less than 400 nanometers.
Abstract:
A method for manufacturing electron tubes in which a photosensitive layer is manufactured in one evacuated vessel, the electrode structure is manufactured in another evacuated vessel, and assembly of the photosensitive layer and electrode structure is accomplished by first placing the first two vessels in a third evacuated vessel, opening the first two vessels, and assembling the contents.