Abstract:
Onto a base member, through which stem pins are passed and holding members are to be joined to the respective surfaces thereof, the stem pins and the holding members are joined by fusion by melting of the base member to arrange a stem with at least three or more layers formed by sandwiching the base member by the holding members. In comparison to a conventional arrangement wherein the stem is arranged as a single layer of glass material and this is melted to fuse the stem pins, the positional precision, flatness, and levelness of both surfaces of the stem are improved.
Abstract:
An electrical circuit for a photomultiplier tube (PMT) is disclosed that reduces power consumption to a point where the PMT may be powered for extended periods with a battery. More specifically, the invention concerns a PMT circuit comprising a low leakage switch and a high voltage capacitor positioned between a resistive divider and each of the PMT dynodes, and a low power control scheme for recharging the capacitors.
Abstract:
The invention relates to a photocathode and the like having such structure for holding a photocathode plate on a light transparent member with good reliability and workability. In the photocathode, claw portions of a holding member fixed to the light transparent member is pressed against the lower surface of a supporting plate so that a photocathode plate is sandwiched between the light transparent member and the supporting plate. Thus, the supporting plate is pressed against the photocathode plate, so that the photocathode plate is pressed against the light transparent plate by the supporting plate. This allows the photocathode plate to be held reliably by the light transparent member. This simple configuration further provides good workability in assembling.
Abstract:
A photomultiplier eliminates the reflection of light off of focusing pieces in a focusing electrode and prevents the photocathode from emitting useless electrons in response to such reflected light by including an oxide film formed over the surface of each focusing piece. The oxide film is also formed on the surface of secondary electron emission pieces in the first and second stage dynodes to eliminate the reflection of light off of the secondary electron emission pieces and to prevent the photocathode from emitting useless electrons in response to such reflected light. Further, a light-absorbing glass partitioning part is provided in a light-receiving faceplate to suppress crosstalk between channels.
Abstract:
The present invention relates to a light-receiving module of a heat-resistant, vibration-resistant type for use in petroleum exploration or the like, and a radiation detecting apparatus equipped with the light-receiving module. The light-receiving module comprises a photomultiplier having a faceplate and a stem opposing each other, a bleeder circuit board provided so as to sandwich the stem together with the faceplate and electrically connected to the photomultiplier, a module case provided so as to accommodate the photomultiplier and the bleeder circuit board, said module case having an opening for exposing the faceplate of the photomultiplier, a step provided on an inner surface of the module case, and a stopper seated on the step, defining the position of the photomultiplier in the module case.
Abstract:
The present invention relates to an electron tube comprising, at least, a cathode electrode, a face plate having a photocathode, and an electron entrance surface provided at a position where the electron emitted from the photocathode reaches. The object of the present invention is to provide an electron tube which can reduce its size and has a structure for improving the workability in its assembling process. In particular, the electron tube according to the present invention has a bonding ring, provided between the face plate and the cathode electrode, for bonding the face plate and the cathode electrode together. The bonding ring is made of a metal material selected from the group consisting of In, Au, Pb, alloys containing In, and alloys containing Pb.
Abstract:
An electron tube, such as, a photomultiplier, includes an aluminum seal ring 4 disposed between a Kovar cylinder 1, and a quartz faceplate 5 having a photocathode 6. The electron tube further includes a borosilicate stem plate 2, an anode 8, and a dynode 7. The aluminum seal ring 4 provides for increased air tightness, reliability, quantum efficiency, and gain.
Abstract:
A focused electron/bombarded hybrid photomultiplier tube comprising a photocathode, focusing electrodes, and a collection anode disposed in a detector body. The collector anode includes a diode for receiving the focused output electron beam from the photocathode. The current gain between the photocathode output current and the detector output signal from the diode is over 1000 at a tube operating voltage of 7 kV. The noise factor has been determined to be 1.1. A hybrid photomultiplier tube includes a photocathode, a photodiode for collecting and multiplying electrons emitted by the photocathode and providing an output signal and electrodes for focusing the electrons on the photodiode. A vacuum envelope encloses a vacuum region between photocathode and the detector. A conductor disposed on or adjacent to a sidewall of the vacuum envelope reduces the effect of electrical charges on the inside wall of the vacuum envelope on the trajectories of the electrons. An ion deflector electrode is disposed adjacent to the photodiode anode and extends photocathode operational life and improves noise factor.
Abstract:
The electron multiplying device according to this invention comprises an electron multiplying unit including dynodes arranged in a plurality of stages. The electron multiplying unit has an incidence opening for an energy beam to be multiplied to enter through, and has the proximal end secured to a base. There is provided a casing for housing the electron multiplying unit. The forward edge of the casing is secured to the base, and a space defined by the base and the casing houses the electron multiplying unit. The casing has an entrance window formed at a position opposed to the incidence opening. Energy beams enter the electron multiplying unit through the entrance window, but the electron multiplying unit itself is housed in the casing to be protected from surrounding air flow and unnecessary energy beams not to be measured.
Abstract:
A photomultiplier assembly for use in gamma cameras, for example, includes an array of head-on type photomultipliers disposed in parallel relation to one another. The array of photomultipliers has a plurality of dead spaces, in which reflectors are respectively disposed. The reflector can reflect light which has entered the corresponding dead space to an upper portion of a side wall of aproximate photomultiplier. A side photocathode surface is formed on an inside surface of the upper portion of the side wall of the photomultiplier. Therefore, the light which has entered the dead space is reflected by the reflector and impinges on the side photocathode surface to be converted into photoelectrons.