Abstract:
A method for fabricating an electron multiplier is provided. The method consists of depositing a random channel layer on a substrate such that the random channel layer is capable of producing a cascade secondary electron emission in response to an incident electron in the presence of an electric field.
Abstract:
A photomultiplier which can be easily made compact has a dynode unit (60) constituted by stacking a plurality of stages of dynode plates (6) in an electron incident direction in a vacuum container constituted by a housing (1) and a base member (4) integrally formed with the housing. Each dynode plate has an engaging member (9) engaged with a connecting pin (11) for applying a voltage at a side surface thereof. Through holes for guiding the connecting pins from the outside of the container are formed in the base member. Each engaging member is arranged not to overlap the remaining engaging members in the stacking direction of the dynode plates. The arrangement position of each engaging member and the arrangement position of the through hole for guiding the corresponding connecting pin to be connected are matched with each other.
Abstract:
A photomultiplier comprising an electron multiplier for minimizing a variation in multiplication factor and noise is characterized in that insulating members (80a,b) are aligned on the same line (606) to insulate a plurality of dynode plates for constituting a dynode unit from each other, thereby preventing a damage to each dynode plate. At the same time, a through hole (600) is formed to fix the insulating member provided to each dynode plate such that a gap is provided between the major surface of the dynode plate and the surface of the insulating member, thereby preventing discharge between dynode plates, which is caused due to dust or the like deposited on the surface of the insulating member.
Abstract:
A photomultiplier has a focusing electrode plate (7) for supporting focusing electrodes, provided between a photocathode (3) and a dynode unit (60). Since the focusing electrode plate has holding springs (7a,7b) which are integrally formed with the focusing electrode plate, resistance-welding becomes unnecessary to prevent field discharge. A concave portion is formed in a main surface of the focusing electrode plate to arrange an insulating member (8a,8b) sandwiched between the focusing electrode plate and the photoelectron incidence side of the dynode unit and partially in contact with the concave portion. With this structure, discharge between the focusing electrode plate and the dynode unit can be prevented.
Abstract:
L' invention concerne un procédé de fabrication d'un intensificateur d'images radiologiques. Avant de les introduire dans l'I.I.R., on recouvre toutes ou partie, d'une ou de toutes les électrodes(G₁, G₂, G₃)d'une couche d'un polymère organique conducteur électronique de l'électricité, et ayant la propriété de réagir chimiquement avec les métaux alcalins déposés sur les électrodes On supprime ainsi l'éclairage parasite de l'écran d'observation (4) dû aux métaux alcalins déposés sur les électrodes lors de l'élaboration de la photocathode (3).
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:
Die Erfindung betrifft ein Verfahren zur Herstellung von Vieikanatplatten für die Verstärkung von optischen Bildern oder anderen flächenhaften Signalverteilungen mittels Sekundärelektronenvervielfachung sowie die Verwendung eines nach diesem Verfahren hergestellten Stapels von Vielkanaiplatten. Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren aufzuzeigen, bei dem bei genau vorgegebenen Querschnitten und Positionen der einzelnen Kanäle die Dicke der Platten ein vielfaches der Kanaldurchmesser betragen kann. Die Aufgabe wird dadurch gelöst, daß
a) zunächst eine Vielkanal-Positiv-Form hergestellt wird, In dem in eine Platte senkrecht oder schräg zur Plattenoberfläche Kanäle mit vorgegebenen Querschnitten und Positionen eingearbeitet werden, b) von der so entstandenen Vielkanal-Positiv-Form unter Verwendung einer mit ihr verbundenen Metallelektrode durch galvanische Abformung und anschließende Entfernung der Vielkanal-Positiv-Form eine metallische Negativ-Form hergestellt wird, und c) die metallische Negativ-Form mit einem für den Aufbau von Vielkanalplatten geeigneten Material aufgefüllt und anschließend die metallische Negativ-Form entfernt wird.
Abstract:
The present invention relates to an alkali metal generating agent and others for formation of a photo-cathode or a secondary-electron emitting surface capable of stably generating an alkali metal. The alkali metal generating agent is used in formation of a photo-cathode for emitting a photoelectron corresponding to incident light, or in formation of a secondary-electron emitting surface for emitting secondary electrons corresponding to an incident electron. Particularly, the alkali metal generating agent contains at least an oxidizer comprising at least one vanadate with an alkali metal ion as a counter cation, and a reducer for reducing the ion. An alkali metal generating device comprises at least the alkali metal generating agent and a case housing it, and the case is provided with a discharge port for discharging the vapor of the alkali metal.
Abstract:
The present invention relates to an alkali metal generating agent and others for formation of a photo-cathode or a secondary-electron emitting surface capable of stably generating an alkali metal. The alkali metal generating agent is used in formation of a photo-cathode for emitting a photoelectron corresponding to incident light, or in formation of a secondary-electron emitting surface for emitting secondary electrons corresponding to an incident electron. Particularly, the alkali metal generating agent contains at least an oxidizer comprising at least one tungstate with an alkali metal ion as a counter cation, and a reducer for reducing the ion. An alkali metal generating device comprises at least the alkali metal generating agent and a case housing it, and the case is provided with a discharge port for discharging the vapor of the alkali metal.