16results about "Multiplier dynodes" patented technology

The application provides a photomultiplier tube and a detector. The photomultiplier tube comprises: a photocathode configured to receive photons and emit photoelectrons based on the received photons; a photomultiplication system located downstream of the photocathode and arranged around a target axis, the target axis coinciding with or being parallel to a central axis of the photomultiplier tube, the photomultiplication system configured to receive the photoelectrons emitted by the photocathode and multiply the photoelectrons; and an anode configured to collect the photoelectrons multiplied by the photomultiplication system and output an anode current based on the collected photoelectrons. According to the embodiments of the application, the carrying capacity of each stage of the multiplication electrode is increased, thereby improving the pulse width response range of the photomultiplier tube and the linear current of the photomultiplier tube.

The invention discloses a quick response end window reflection type photomultiplier, which belongs to the field of photomultiplier testing and comprises a micro-curved spherical incident window, a focusing disc, a plane reflection type cathode, a grid mesh, a fixed plate, an accelerator rod, a dynode DY1-DYn and an anode. According to the invention, the effective working area of the photoelectric cathode is optimized, the accelerator rod is placed according to the electric field distribution, the relative position of the dynode is changed to optimize the electron motion trail, the incident light is focused to the effective position of the cathode surface electric field by using the micro-curved spherical incident light window, and the photoelectron generation position is optimized; a proper accelerator rod is placed according to the sparsity degree of distribution of an electric field near a cathode surface, so that electrons are better converged, the first multiplier tube and the second multiplier tube are designed to be of an asymmetric structure, and the distance and the included angle are adjusted to optimize an electron movement track to realize quick response.

The invention discloses a small-halo vacuum photoelectric device and application thereof. The small-halo vacuum photoelectric device comprises a first ceramic ring, a second ceramic ring, a first metal ring, a second metal ring, an elastic pressing ring and an electron multiplication plate with a conductive input surface and a conductive output surface, a first ceramic ring is arranged on the bottom surface of the first metal ring; a second metal ring is arranged on the bottom surface of the first ceramic ring; the second metal ring is arranged on the top surface of the second ceramic ring; an anode is arranged on the bottom surface of the second ceramic ring. By arranging an angle from 89 degrees to 86 degrees on the elastic compression ring of the structure device, plane contact between the elastic compression ring and the conductive input surface of the electron multiplication plate is realized, and local or complete non-electric contact between the elastic compression ring and the electron multiplication plate and related surfaces thereof is eliminated; the halo phenomenon generated by stray light generated by surface deformation of the electron multiplier plate is eliminated, and the imaging quality is improved.

Systems and methods for suppressing X-ray interference in radiation portal monitors are provided. A radiation portal monitor includes a scintillator configured to convert high energy photons into low energy photons, and a photomultiplier tube (PMT) coupled to the scintillator, the PMT including a photocathode configured to convert the low energy photons into electrons, and a series of dynodes configured to cascade the electrons to facilitate detecting gamma events. The radiation portal monitor further includes an electron deflecting arrangement configured to selectively deflect the electrons before they encounter the series of dynodes.

An electron tube 1 includes: a photoelectric surface 3 converting incident light into photoelectrons; a plurality of dynodes 11 and an anode 6; an insulating substrate 12 holding the dynodes 11 and the anode 6 in a state where the dynodes 11 and 11 are electrically insulated from each other, and the dynode 11 and the anode 6 are electrically insulated from each other; and a housing 2 accommodating the dynodes 11, the anode 6, and the insulating substrate 12, wherein the insulating substrate 12 includes: a base layer 21 made of a polycrystalline material and having an electrical insulation property; an intermediate layer 22 made of an amorphous material and having an electrical insulation property; and a surface layer 23 made of a material containing carbon and being smaller in electric resistance than the intermediate layer 22.

An electron tube includes: a photoelectric surface converting incident light into photoelectrons; a plurality of dynodes and an anode; an insulating substrate holding the dynodes and the anode in a state where the dynodes are electrically insulated from each other, and the dynode and the anode are electrically insulated from each other; and a housing accommodating the dynodes, the anode, and the insulating substrate, wherein the insulating substrate includes: a base layer made of a polycrystalline material and having an electrical insulation property; an intermediate layer made of an amorphous material and having an electrical insulation property; and a surface layer made of a material containing carbon and being smaller in electric resistance than the intermediate layer.

An ion detector includes a conversion dynode including a conversion region where electrons are emitted by incident ions, an electron multiplier including an electron incident surface on which the electrons are incident, and an aperture electrode including an aperture through which the electrons traveling from the conversion region to the electron incident surface pass. The conversion region is a region protruding toward a space where the electrons are emitted.

This invention relates to an electron counting device, an electron counting system, and a measurement method for a micro-electron beam. The electron counting system includes a current measuring unit and an electron counting device, with the output end of a Faraday cylinder connected to the current measuring unit. The electron counting device includes a Faraday cylinder and an electron multiplier tube. The electron multiplier tube is housed within the Faraday cylinder, with a gap between the outer peripheral wall of the electron multiplier tube and the inner peripheral wall of the Faraday cylinder. The Faraday cylinder is connected to a second insulating tube and the electron multiplier tube via a first insulating tube. The measurement process involves: multiplying the electron beam – measuring the electron current value – calculating the number of electrons. Compared to directly collecting electrons using the Faraday cylinder inside the electron multiplier tube, the electrons amplified by the electron multiplier tube are input into the Faraday cylinder for measurement, improving the accuracy of electron measurement.

To provide an ion detector capable of determining a component to be ionized with high sensitivity without depending on the polarity of ions.SOLUTION: An ion detector (24) includes a conversion dynode (241), a secondary electron multiplier (242), and a DC voltage application unit (243) that applies a DC voltage between the conversion dynode (241) and the secondary electron multiplier (242), in which a part or all of a surface of the conversion dynode (241) including an ion collision surface (2410) with which ions collide is made of a material containing one or more elements of titanium, vanadium, and chromium at a higher density than iron and aluminum.SELECTED DRAWING: Figure 1

This invention discloses a photomultiplier tube (PMT) dynode film preparation system and method belonging to the field of PMT technology. The system includes a PMT, a vacuum system, and an alkali source assembly. The alkali source assembly includes an external glass tube and internal K, Na, and Cs sources. One end of the glass tube is closed, and the other end is connected to the vacuum system via a tail tube. One end of the PMT is also closed, and the other end is connected to the vacuum system via a tail tube. The K, Na, and Cs sources are connected to pin electrodes via nickel wires to form a circuit. Eleven pin electrodes are led out from the inside of the PMT. This invention can accurately and effectively monitor the secondary electron emission capability of the dynode film, solving the problem of lack of quality control in the dynode preparation process. Furthermore, it improves the secondary electron emission coefficient of the dynode film, resulting in a significant increase in overall PMT gain and achieving good consistency.

The invention discloses a photomultiplier and electronic equipment, and the photomultiplier comprises a first reflector which is used for receiving incident light outside the photomultiplier and reflecting the incident light; the first reflecting photocathode is used for receiving the reflected light of the first reflecting mirror and generating photoelectrons; and the multiplication system is used for multiplying the photoelectrons generated by the first reflection photocathode.

The invention discloses a high-gain copper beryllium alloy secondary electron emitter and a preparation method thereof, and relates to the technical field of material preparation, and the preparation method comprises the following steps: carrying out pulse electrolytic polishing surface pretreatment on a punch-formed copper beryllium alloy base material, then putting the copper beryllium alloy base material subjected to surface pretreatment into a tubular furnace, and heating the tubular furnace to obtain a copper beryllium alloy secondary electron emitter; after argon and hydrogen mixed gas is introduced for gas washing, vacuumizing is conducted, then the tubular furnace is heated, low-oxygen-pressure thermal activation treatment is conducted on the copper-beryllium alloy base material in two steps, a beryllium oxide active layer with the high secondary electron emission coefficient is formed on the surface, and the high-gain copper-beryllium alloy secondary electron emitter is obtained. The beryllium oxide active layer is uniform, compact and low in roughness, the copper beryllium alloy secondary emitter is high in secondary electron emission coefficient and stable in performance, and the problem that a conventional copper beryllium alloy secondary electron emitter is insufficient and unstable in performance is effectively solved.

The application discloses a MeV-level gamma-sensitive electron multiplier and a preparation method thereof, relates to the technical field of gamma detectors, and gamma rays enter a tubular shell through a collimator, secondary electrons are generated through the interaction of a metal cathode and the incident gamma rays, a substrate is fixed on the inner surface of the metal cathode, and the surface of the substrate is composed of negative electron affinity material in the micron scale range, so that the secondary electrons with low energy and multiplied number are generated under the excitation of the secondary electrons penetrating the substrate; the secondary electrons emitted from the surface of the negative electron affinity material are cascade multiplied through a microchannel plate, and finally the secondary electrons multiplied through the microchannel plate are collected through a metal anode to form an output signal, so that the count rate and the action time information of the gamma rays to be measured collimated through the collimator are detected; the MeV-level gamma-sensitive electron multiplier has the detection characteristics of high gain and fast response to MeV gamma rays.

An arithmetic device that calculates a gain of a photomultiplier tube includes: an acquisition unit that acquires a digital signal based on a dark pulse output from the photomultiplier tube placed in a dark state; and a calculation unit that calculates a total number of electrons in the dark pulse based on the digital signal and calculates the gain of the photomultiplier tube based on the total number of electrons.

The invention relates to the technical field of photomultipliers, in particular to a sensitization method and sensitization system for an alloy dynode part with high secondary electron emission performance, and the sensitization system comprises a support which is provided with a heating furnace; the transfer chamber is connected to the support, a first cavity is formed in the transfer chamber, the transfer chamber is provided with a vacuum gauge, a first valve and a second valve, and the vacuum gauge is used for monitoring the vacuum degree of the first cavity. According to the method, the dynode part is subjected to sensitization treatment in the environment with the temperature not higher than 400 DEG C, evaporation of active elements can be effectively inhibited, and then the enrichment amount of effective elements on the surface of the alloy dynode is remarkably increased; meanwhile, ions are drawn by an electric field to bombard and permeate the surface of the part, so that an active and clean state can be constructed for the surface of the part, oxidation or nitridation of a surface material can be further promoted, and effective elements such as beryllium on the surface of the alloy are fully converted into oxides or nitrides; and finally, a compact secondary electron emission layer with high secondary electron emission performance is formed.