24 results about "Dynode" patented technology

This MCP detector (1) is provided with: an MCP (3) having an input surface (3a) into which electrons (e1) are input; multiplication units (11A, 11B) that multiply electrons generated in accordance with the input of the electrons (e1); an output surface (3b) that outputs the electrons (e2) multiplied by the multiplication units (11A, 11B); a planar dynode (5) which is separated from the output surface (3b), is arranged substantially parallel to the output surface (3b), and multiplies the electrons (e2) output from the output surface (3b); and an electron collection unit (7) that is disposed between the output surface (3b) and the dynode (5), is separated from the output surface (3b) and the dynode (5), and collects the electrons (e3) multiplied by the dynode (5), the electron collection unit (7) having: a line anode (7a) that includes a metal line extending along a plane substantially parallel to the output surface (3b); and a wire anode (7b) that is electrically insulated from the wire anode (7a), includes a metal wire extending along the plane, and is disposed between the wire anode (7a) and the dynode (5).

The invention discloses a method for simply and rapidly installing a dynode of an electron multiplier, and belongs to the field of electron multiplier assembly. According to the method, extra tools are not needed, and only three long screws and a pair of pointed tweezers need to be additionally used. According to the method, the problem that time and labor are wasted when the ceramic plate of the multiplier and nine dynodes are folded and aligned is solved, and the installation of the dynodes can be effectively accelerated. During installation, the three long screws are inserted into the through holes of the ceramic plate bottom plate, then the screws are sleeved with the limiting stainless steel cylinders respectively, then the nine dynodes and the collecting plate are sequentially installed on the ceramic plate bottom plate, then the ceramic plate top plate is sleeved with the three screws, the hexagonal studs are screwed, and the ceramic plate top plate is installed on the ceramic plate bottom plate. And the distance between the top and bottom ceramic plates is about 4mm longer than that of the limiting stainless steel cylinder. The nine dynodes and the collecting plate are sequentially stirred through pointed tweezers, the upper feet of the dynodes and the collecting plate enter the small mounting holes corresponding to the top plate of the ceramic plate, the lower feet of the dynodes do not leave the small mounting holes corresponding to the bottom ceramic plate, and the top ceramic plate and the bottom ceramic plate are tightened after completion. And the long screws are replaced by the original screws of the multiplier in sequence, and the dynode is assembled.

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 belongs to the technical field of vacuum electronic devices, and particularly relates to a dynode with an edge expansion type inner substrate and an electron multiplier comprising the dynode. The dynode comprises a grid mesh assembly, a base frame box and an edge expansion type inner substrate, and the inner substrate is located in the base frame box. The lining bottom comprises an arc-shaped side wall part, an upper wall, a lower wall and a bent part; the bent parts are arranged between the arc-shaped side wall part and the upper wall and between the arc-shaped side wall and the lower wall; the base frame box comprises a side wall, and an upper baffle and a lower baffle which are connected with the side wall; the arc-shaped side wall part of the lining bottom is attached to the side wall of the base frame box, the upper wall of the lining bottom is tightly attached to the upper baffle of the base frame box, and the lower wall of the lining bottom is tightly attached to the lower baffle of the base frame box. The inner substrate structure enables the electric field in the dynode to change, and especially the electric field intensity at the corners in the dynode, namely the area where the bent part is located, is obviously changed. The problem of low dynode electron collection efficiency is solved, and the gain of the electron multiplier is improved.

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 relates to a micro-channel plate manufacturing method based on a mold pouring method and a micro-channel plate. The method comprises the steps that a silicon microchannel array substrate is placed on a metal mold material, and holes of the silicon microchannel array substrate face downwards; based on a crucible and a vacuum hot melting filling device, liquefying a metal mold material and filling the metal mold material into the silicon micro-channel array substrate; cooling to realize metal curing to obtain a metal mold precursor, and corroding silicon to obtain a metal mold; putting the high borosilicate glass material and the metal mold into a crucible, and filling the high borosilicate glass material into the metal mold based on a vacuum hot melting filling device; cooling to obtain a glass-metal complex, and corroding a metal material to obtain a micro-channel plate substrate; carrying out hydroxylation treatment; and preparing a dynode on the micro-channel plate substrate, and performing annealing treatment to obtain the micro-channel plate. The microchannel plate with a high softening point and high purity can be manufactured, the yield is high, noise is low, exhaust in the channel is sufficient, and the service life of the image tube is prolonged.

A method for determining a performance parameter of an electron multiplier (e.g. parameter indicative of gain) comprises comparing an electron flux of a first electron emissive surface with an electron flux of a second electron emissive surface, or of an electron collector. The electron emissive surfaces form part of an electron multiplication chain, and may be discrete dynodes or provided by a single electron emission surface (e.g. a channel of a channel electron multiplier, or a plate of a microchannel plate electron multiplier). The first electron emissive surface may be earlier in the chain and less susceptible to electron flux-mediated gain degradation. A current ratio from the two electron emissive surfaces may be determined and compared with a comparator. An operating parameter (e.g. voltage bias) of the electron multiplier may be altered based on the determined performance parameter or current ratio. The invention may obviate or reduces the need for manual gain adjustment by adjusting the gain continuously and automatically to account for gain instability based on the comparison.

The invention relates to the field of electron multiplication sources, and provides an electron multiplication source and application thereof, and the electron multiplication source comprises a tube body with a tube cavity; the electron source comprises an optical fiber and an electron excitation layer; the anode assembly is located on an emergent path of the electron beam, is opposite to the light emergent end of the optical fiber and is arranged at an interval; the dynode group comprises at least one dynode arranged on the cavity wall of the tube cavity; and a power supply assembly. The electron multiplication source has the advantages of being small in size, high in integration degree, good in stability, high in multiplication effect and the like.

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.

An ion detector (24) comprises a conversion dynode (241), a secondary electron multiplier tube (242), and a DC voltage application unit (243) that applies a DC voltage between the conversion dynode (241) and the secondary electron multiplier tube (242). A part or all of a surface of the conversion dynode (241), including an ion collision surface (2410) where ions collide, is made of a substance containing one or more elements selected from the group consisting of titanium, vanadium, and chromium at a higher density than iron and aluminum.

This MCP detector (1) is provided with: an MCP (3) having an input surface (3a) into which electrons (e1) are input; multiplication units (11A, 11B) that multiply electrons generated in accordance with the input of the electrons (e1); an output surface (3b) that outputs the electrons (e2) multiplied by the multiplication units (11A, 11B); a planar dynode (5) which is separated from the output surface (3b), is arranged substantially parallel to the output surface (3b), and multiplies the electrons (e2) output from the output surface (3b); a positive electrode (8) that is disposed between the output surface (3b) and the dynode (5) so as to be separated from the output surface (3b) and the dynode (5), and that collects the electrons (e3) multiplied by the dynode (5); and a dynode (7) that is disposed between the anode (8) and the dynode (5) so as to be separated from the anode (8) and the dynode (5), further multiplies the electrons (e3) multiplied by the dynode (5), and passes toward the anode (8).

The invention discloses a preparation method of a secondary electron emission layer of a copper-beryllium alloy dynode for a high-gain photomultiplier, which comprises the following steps: firstly, carrying out high-temperature annealing treatment on a copper-beryllium alloy strip, and then, carrying out physical and chemical polishing to increase the degree of finish; before the secondary electron emission film layer is prepared on the surface of the copper-beryllium alloy, the grain size of the copper-beryllium alloy is increased in a high-temperature annealing manner, so that a BeO film with a larger grain size is subsequently generated; in addition, by adding the heat preservation process, beryllium of the copper-beryllium alloy matrix is gathered towards the surface, the thickness of the BeO film layer is increased, and the secondary electron emission performance is improved.

A sample analyzer, a photometer and a photometric system. The sample analyzer (2000) comprises a light source (100), a photometer (600) and a processor (500); the photometer (600) comprises a photoelectric conversion assembly (401) and a signal processing assembly (400); the photoelectric conversion assembly (401) comprises a photomultiplier tube (200) and a voltage divider circuit (300), an input end node of the voltage divider circuit (300) being connected to the cathode of the photomultiplier tube (200), and an output end node of the voltage divider circuit (300) being connected to the anode of the photomultiplier tube (200). N+1 voltage divider nodes are sequentially arranged between the input end node and the output end node, and the N+1 voltage divider nodes are respectively and sequentially connected to a photoelectron focusing electrode and N dynodes of the photomultiplier tube (200), such that voltage divider branches between two adjacent nodes form N+2 divided voltages; at least one of the divided voltage corresponding to the input end node, the divided voltage corresponding to the voltage divider node N+1, and the divided voltage corresponding to the voltage divider node N is configured to be less than the divided voltages corresponding to the other voltage divider nodes.

A charged particle detector includes a microchannel plate having an input surface having electrons (charged particles) input thereon, a multiplication portion performing multiplication of electrons while maintaining positional information of the electrons, and an output surface outputting electrons multiplied by the multiplication portion; a multi-dynode having a plurality of dynodes multiplying the electrons output from the output surface, and insulation regions positioned between the dynodes; and an anode disposed in a spatial region between the output surface and the multi-dynode, and having collection portions for collecting electrons multiplied by the dynodes and aperture portions for allowing electrons output from the output surface to pass therethrough to the dynodes side. All of the insulation regions overlap the collection portions when viewed in an output direction of the electrons from the output surface.

A sample analyzer, a photometer, and a photometric system. The sample analyzer (2000) comprises a light source (100), a photometer (600), and a processor (500); the photometer (600) comprises a photoelectric conversion assembly (401) and a signal processing assembly (400); the photoelectric conversion assembly (401) comprises a photomultiplier tube (200) and a voltage divider circuit (300); an input end node of the voltage divider circuit (300) is connected to a cathode of the photomultiplier tube (200); an output end node of the voltage divider circuit (300) is connected to an anode of the photomultiplier tube (200); N+1 voltage divider nodes are sequentially arranged between the input end node and the output end node; the N+1 voltage divider nodes are respectively connected to a photoelectron focusing electrode and N dynodes of the photomultiplier tube (200) in sequence, and voltage divider branches between adjacent nodes form N+2 divided voltages; at least one of the divided voltage corresponding to the input end node, the divided voltage corresponding to the voltage divider node N+1, and the divided voltage corresponding to the voltage divider node N is configured to be less than the divided voltages corresponding to the other voltage divider nodes.

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.

This invention discloses a laser particulate matter sensor, including a reflection module comprising multiple reflectors. A first beam emitted from a laser source intersects with a gas path, the intersection area being a measurement-sensitive region. The first beam is reflected by the reflection module to form a second beam, which passes through the measurement-sensitive region. A photoelectric conversion unit comprises multiple photoelectric conversion units for detecting the scattered signals of the first or second beam. This invention achieves simultaneous acquisition of both vertical and forward signals, and doubles the amount of vertical and forward scattered signals. It significantly improves the detection accuracy of the laser particulate matter sensor for PM2.5 and can effectively identify the concentration of large particles such as PM10, providing high-precision detection results.

Provided is a photomultiplier tube including: a photoelectric surface configured to emit photoelectrons in response to incident light; an electron multiplying unit including a plurality of dynodes configured to emit secondary electrons in response to incidence of the photoelectrons emitted from the photoelectric surface and to multiply the secondary electrons; an acceleration electrode disposed between the photoelectric surface and the electron multiplying unit and configured to accelerate the photoelectrons to be incident to the electron multiplying unit; and a tubular accommodation container accommodating the photoelectric surface, the acceleration electrode, and the electron multiplying unit.

The application discloses a high-collection-efficiency large-area micro-channel plate photomultiplier, which comprises a vacuum glass container, a photoelectric cathode, a focusing electrode, a micro-channel plate electron multiplier, an anode and a power supply wire; the photoelectric cathode is covered on the inner surface of the vacuum glass container; the focusing electrode is arranged directly below the photoelectric cathode; the diameter of the top opening of the focusing electrode is larger than the diameter of the bottom opening and smaller than the diameter of the photoelectric cathode; a high secondary electron emission material layer is uniformly covered on the inner wall of the focusing electrode; the micro-channel plate electron multiplier is arranged at the bottom opening of the focusing electrode; the voltage of the focusing electrode is smaller than the input voltage of the micro-channel plate electron multiplier; the anode is arranged directly below the output end of the micro-channel plate electron multiplier; and the photoelectric cathode, the focusing electrode, the micro-channel plate electron multiplier and the anode are powered through the power supply wire. Under the high collection effect, the collection efficiency of the large-area micro-channel plate photomultiplier can be greatly improved.

The effective quantum efficiency of a metal-channel photomultiplier tube can be increased with an optical system. The optical system can direct incident light from areas of low efficiency on the cathode of the metal-channel photomultiplier tube instead to areas of high efficiency on the cathode. These high-efficiency areas of the cathode can correspond to a position between the dynode structure.

The utility model relates to the technical field of photoelectricity, in particular to a circuit structure capable of reducing influence of dark current of a photomultiplier, which comprises the photomultiplier and an integrating circuit, and the anode of the photomultiplier is connected with a common terminal of a single-pole double-throw analog switch. One output terminal of the single-pole double-throw analog switch is connected with the input end of the integrating circuit, and the other output terminal of the single-pole double-throw analog switch is grounded; and the single-pole double-throw analog switch is controlled by the photomultiplier. According to the utility model, the structure is simple, the operation is convenient, in practical application, the adjustable resistor R1 is adjusted to offset dark current to the greatest extent, and the dynode of the photomultiplier is utilized to control the single-pole double-throw analog switch, so that the dark current does not flow into the integrating circuit when the anode of the photomultiplier has no pulse output; the contribution rate of the dark current to an integral result is reduced, and the problem that the dark current has a great influence on a measurement result is solved.

The invention discloses a method for preparing a beryllium-copper-based high-entropy alloy strip by adopting vacuum magnetic suspension, and relates to a method for preparing a beryllium-copper-based alloy strip for a photomultiplier. The invention aims to solve the problems that the traditional Cu-Be alloy strip can only form a BeO single film, the secondary electronic performance is insufficient, and multiple performances are difficult to meet; the traditional smelted high-entropy alloy is easy to generate segregation; the problems of blindness, easy damage to a matrix, many chemical residues and the like of a traditional brushing process are solved. The method comprises the following steps: 1, vacuum magnetic suspension casting; 2, throwing the blank; 3, quenching; 4, mechanical brushing; (5) rolling; 6, rolling by a four-roller mill; 7, rolling by using a six-roller mill; 8, performing online annealing; 9, rolling by a 20-roller rolling mill; tenthly, online annealing is conducted; 11, trimming; 12, stretch bending and straightening; 13, alternating current cleaning and brushing; and 14, rolling. The method is different from a traditional strip preparation process combining smelting and mechanical brushing, blank manufacturing is conducted in a small vacuum magnetic suspension smelting and continuous blank drawing mode, surface treatment is conducted on the rolled plate through the composite surface treatment technology combining the electric field effect and mechanical brushing, and controllable coil weight preparation and targeted surface cleaning are achieved. According to the preparation method, the Cu-Be-Al-Mg-Y-Ce alloy composite strip for the photomultiplier can be obtained.

The invention provides an ion detector which can quantify ionized components with high sensitivity without depending on the polarity of ions. An ion detector (24) is provided with a conversion dynode (241), a secondary electron multiplier tube (242), and a DC voltage application unit (243) that applies a DC voltage between the conversion dynode (241) and the secondary electron multiplier tube (242), the surface of the conversion dynode (241) including a part or the entirety of an ion collision surface (2410) on which ions collide. The aluminum alloy material contains one or more elements selected from among titanium, vanadium and chromium at a higher density than iron and aluminum.