Abstract: A photomultiplier excellent in vibration resistance and improved in pulse linearity characteristic and time-response. The fourth, and sixth to ninth dynodes (Dy4, Dy6 to Dy9) have a similar shape to that of the second dynode (Dy2). The third and fifth dynodes (dy3, Dy5) are smaller than the dynode (Dy2). The first to tenth dynodes (Dy1 to Dy10) are so arranged that the dynode inner space path defined between opposed dynodes is perpendicular to the tube axis (X). The anode (A) is a mesh anode (A), and is opposed to the dynode (Dy2) with respect to the tube axis (X).

Abstract: In this photomultiplier tube 1, light incident on a light-receiving faceplate 3 is converted into photoelectrons by a photosensitive surface 3a, and the photoelectrons strike a dynode 4 to emit many secondary electrons. The secondary electrons are then collected by a mesh-like anode 5. Since the anode 5 is disposed to be parallel to the photosensitive surface 3a, the photoelectrons emerging from the photosensitive surface 3a can easily pass through a mesh portion 5a, and many photoelectrons can be made to strike the dynode 4. As the number of photoelectrons incident on the dynode 4 increases, the number of secondary electrons from the dynode 4 increases. This improves the gain characteristics of the photomultiplier tube 1. Since a secondary electron emission surface 4a of the dynode 4 is tilted with respect to the anode 5, photoelectrons having passed through the anode 5 obliquely strike the secondary electron emission surface 4a of the dynode 4.

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: 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: The present invention relates to a magnetic shielding case comprising a structure for improving the uniformity in light receiving sensitivity of a phomultiplier while maintaining sufficient magnetic shielding function, and a light detecting apparatus including this magnetic shielding case. This apparatus comprises a photomultiplier and a magnetic shielding case accommodating the photomultiplier. In particular the magnetic shielding case comprises a housing having an opening for transmitting therethrough light to be detected which is directed to the photomultiplier; a lens element for guiding the light to be detected into an effective region on a photocathode; and a positioning structure for placing the photomultiplier at a desired position with respect to the lens element.

Abstract: The present invention relates to a versatile side-on type photomultiplier comprising a structure for improving the uniformity in light receiving sensitivity. Disposed on the outer peripheral surface of a sealed envelope of this photomultiplier is a restricting member which guides light to be detected into, of the light receiving surface of a photocathode, an effective region where the light receiving sensitivity is high, thereby restraining the light to be detected from reaching the outside of the effective region.

Abstract: This invention relates to an electron tube which stabilizes the orbits of electrons accelerated and focused by an electron lens and has a structure for effectively suppressing noise generated due to discharge. This electron tube has, at two ends of an insulating container, a cathode electrode and an anode electrode which constitute the electron lens. Particularly, in the electron tube, one end of the cathode electrode and a photocathode are supported by a conductive member arranged at one end of the insulating container, and the cathode electrode is electrically connected to the photocathode. The cathode electrode partially extends to a stem along the inner wall of the insulating container and is tapered toward the stem so that the distal end portion of the cathode electrode is separated from the inner wall of the insulating container.

Abstract: The present invention relates to an electron tube includes, at least, a cathode electrode and a face plate having a photocathode which are arranged at one end of a body, and a stem arranged at the other end of the body for defining the position of an electron entrance surface 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 in accordance with the present invention comprises 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: 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 through a container. Particularly, the area of the opening of the confining mechanism is 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 includes a photocathode (3); an electron multiplier section (60) for cascade-multiplying photoelectrons emitted from the photocathode (3); a faceplate (2) provided with the photocathode (3); a metal housing (1) accommodating the photocathode (3) and the electron multiplier section (60); and a structure disposed on the faceplate (2) for increasing the effective light entrance region of the faceplate (2). In a preferred embodiment the subject structure includes a lens element (30) attached to the faceplate for increasing the effective light entrance region of the faceplate (2). In order to improve the optical coupling efficiency, either the faceplate (2), or the lens element (30), or both the faceplate (2) and the lens element (30) may further include a protrusion.

Abstract: The present invention relates to a versatile side-on type photomultiplier comprising a structure for improving the uniformity in light receiving sensitivity. This photomultiplier comprises a positioning structure for precisely positioning, with respect to the light receiving surface of a photocathode, a lens element which guides light to be detected to a photocathode and constitutes a part of an envelope accommodating the photocathode. The precisely positioned lens element guides the light to be detected into, of the light receiving surface of the photocathode, an effective region where the light receiving sensitivity is high, thereby restraining the light to be detected from reaching the outside of the effective region.

Abstract: The present invention concerns a photomultiplier having a lamination structure of fine mesh dynodes arranged at predetermined intervals, capable of detecting photons even in a high magnetic field. This photomultiplier is arranged so that hollow pipes penetrating electrodes for supporting the fine mesh dynodes define the lamination structure of an electron multiplier unit. This arrangement permits the intervals between the fine mesh dynodes to be accurately controlled, thereby obtaining the photomultiplier production errors of which are well suppressed and preventing that the fine mesh dynodes are ripped.

Abstract: In a photomultiplier tube, a second dynode Dy2 is located in confrontation with a first dynode Dy1 in an electron multiplication portion 6. The second dynode Dy2 is made of material that has a secondary electron emission gain which is substantially saturated with respect to an electric voltage applied thereto.

Abstract: The present invention relates to a linear multi-anode photomultiplier or electron multiplier on which a plurality of light beams to be measured or energy beams of electrons, ions and so forth are incident one-dimensionally. The object of the present invention is to prevent crosstalk between dynode arrays caused by leaking electrons. A transmission type photomultiplier is characterized in that the direction of secondary electron emission of the first-stage dynode of each dynode array is set in the opposite direction at 180.degree. from that of an adjacent dynode array. Then, adjacent dynode arrays will not oppose each other but are shifted from each other at a predetermined distance in the lateral direction. Accordingly, even if electrons leak from a gap between dynodes of a certain dynode array, the leaking electrons will not enter the adjacent dynode array, thereby preventing crosstalk.

Abstract: The present invention pertains to a photomultiplier of head-on type that has a transparent tubular glass bulb and a principal photocathode formed on the internal surface of a closed end of the glass bulb, that is, on the internal surface of a light entrance window. In addition, this photomultiplier has a side photocathode formed on the entire internal surface of side wall of the glass bulb in the region adjacent to the principal photocathode. A reflection film is formed on the outer surface of side wall of the glass bulb and opposes to the side photocathode. Some light entering the peripheral portion of the light entrance window of the glass bulb and traveling toward the outer surface of side wall is reflected inwardly by the reflection film and reaches the side photocathode, where the light is to be converted into photoelectrons. The photoelectrons are guided to the electron multiplying unit in glass bulb, where the photoelectrons are multiplied and detected by an anode.

Abstract: An electron multiplier tube including a grid type of plural dynode arrays arranged in a first direction with a multistage structure for successively multiplying electrons incident thereto and an anode provided below the multistage structure of dynode arrays for collecting the multiplied electrons to output an amplified electrical signal, each of the dynode arrays including plural rod-shaped dynode elements arranged in a second direction and a mesh electrode provided over each of the dynode arrays for providing an equipotential, wherein the multistage structure of dynode arrays includes at least one group of neighboring dynode arrays whose dynode elements are arranged so as to be aligned with one another in the first direction without displacement. Each of the dynode elements has a substantially isosceles trapezoid section, both side legs of the trapezoid being slightly inwardly curved to effectively receive the incident electrons which have been emitted from a dynode array at an upper stage.

Abstract: A photomultiplier tube includes a tube, a focussing electrode unit formed with a photoelectron transmission hole whose center is positioned offset from a central axis of the tube and a dynode positioned in confrontation with the transmission hole. A center of the dynode is also offset from the central axis of the tube. A grid type electrodes array are positioned at the same axial position of the dynode and positioned beside the dynode in a radial direction of the tube. The focussing electrode provides desirable uniformity in distribution of photoelectronics over the dynode even by the deviating position of the photoelectron transmission hole and the dynode. By positioning the dynode away from the central axis in the radial direction of the tube, the grid type electrode array can be positioned beside the dynode.

Abstract: A photomultiplier tube comprising a photocathode, a plurality of mesh dynodes arranged parallel to the photocathode, an anode that is disposed in a face-to-face relationship with the photocathode in such a manner that the mesh dynodes are interposed between the anode and the photocathode, the anode being divided into segments larger than the openings of each dynode, and at least one layer of focusing electrode for focusing an electron beam by the lens action which is disposed between the photocathode and the anode.