Abstract:
A side tube includes a tube head, a funnel-shaped connection neck, and a tube main body, which are arranged along a tube axis and which are integrated together into the side tube. The size of a cross section of the tube head perpendicular to the tube axis is larger than the size of a cross section of the tube main body perpendicular to the tube axis. The radius of curvature of rounded corners of the tube head is smaller than the radius of curvature of rounded corners of the tube main body. The length of the tube head along the tube axis is shorter than the length of the tube main body along the tube axis. One surface of a faceplate is connected to the tube head. A photocathode is formed on the surface of the faceplate in its area located inside the tube head.
Abstract:
A photomultiplier tube has a side tube with a stem plate fixed on one end and a faceplate fixed on the other. The side tube is formed of metal, and at least the portion of the stem plate contacting the metal side tube is formed of metal. The side tube and stem plate are fused together by laser welding or electron beam welding to form an airtight vessel, such that the outer edge of the stem plate does not protrude further externally than the outer surface of the side tube.
Abstract:
In a photomultiplier, focusing pieces of a focusing electrode are formed with sufficient height that the photocathode in the adjacent channels cannot be viewed from the first and second stage dynodes of each channel in order to prevent light reflected from the first and second stage dynodes from returning to the adjacent channels. This construction prevents the photocathode from emitting undesired electrons, thereby suppressing crosstalk. Further, by arranging condensing lenses on the outer surface of a light-receiving faceplate in correspondence with each channel, light is reliably condensed in each channel. Further, an oxide film formed. over the surface of the focusing pieces prevents the reflection of light off the focusing pieces.
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 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.
Abstract:
A photomultiplier tube and a method and apparatus for molding an optical coupler thereto are described. An optical coupler molding fixture includes a frame and a frame base. A photomultiplier tube is positioned within the frame between a spring and a shim. The optical coupler is formed with a mold which is positioned against the shim. A cavity is created radially interior to the shim between the photomultiplier tube and the mold. The optical coupler is molded to a faceplate of the photomultiplier tube with the fixture oriented so that its longitudinal axis L is parallel to the ground. A clamping structure presses the mold against the shim and provides the optical coupler material a non-leak space in which to cure. The optical coupler material is injected into the mold through a fill hole, and may be injected at ambient temperature. Curing time may range from one week at ambient temperatures to four hours at 65° C. The mold can be machined to create any form desired for the optical coupler. The shim can be sized and configured to allow for adjustment in the thickness of the optical coupler. The optical coupler may be as thin as less than 0.015 inches in thickness. If, for example, a thicker optical coupler is desired, the shim may be made thicker. The edge of the photomultiplier tube housing which abuts the shim is checked for its perpendicularity to the longitudinal axis L. Without perpendicularity, proper alignment of the photomultiplier tube is less likely.
Abstract:
An electron tube in which a side tube and a faceplate are sealed together using a malleable metal with a low melting point. The metal is made to spread out along the outer surface of the faceplate due to pressure from a first sealing portion of a sealing metal support member and along the peripheral surface of the electron tube due to pressure from a second sealing portion of the sealing metal support member. Accordingly, the outer side of the corner portion formed by the faceplate and the side tube is covered with the metal. This construction not only reliably secures the input faceplate to the side tube, but also is extremely effective in preserving the airtightness of the electron tube. Since the first sealing portion is pressed toward the faceplate, an appropriate pressure can be applied to the metal interposed between the first sealing portion and the faceplate, improving the sealability of the metal against the faceplate and the first sealing portion. This construction is also appropriate for mass production of electron tubes.
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 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:
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.