36 results about "Dynode" patented technology

The present invention belongs to the technical field of electron multipliers, and relates to a rotary multi-stage separated dynode multiplication structure, which includes a turntable, a plurality of rotary dynodes, and a fixed dynode arranged outside the turntable; the fixed dynode includes a first cathode plate, a grid, a first upper baffle connected to the upper end of the first cathode plate, and a first lower baffle connected to the lower end of the first cathode plate. The first cathode plate is an arc-shaped plate, and the grid is connected to the side of the first cathode plate; the rotary dynode includes a second cathode plate, a second upper baffle, and a second lower baffle. The second cathode plate has the same shape as the first cathode plate, and both the second upper baffle and the second lower baffle are leaf-shaped plates; the plurality of rotary dynodes includes N working dynodes and a spare dynode, and the turntable is connected with a rotating device. The spare dynode can replace the dynode with deteriorated performance, thereby prolonging the service life of the electron multiplier. By rotation, the problem of too rapid deterioration of the performance of the first-stage and last-stage dynodes can be solved, and the gain of the electron multiplier can be improved.

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.

This photomultiplier tube includes a photoelectric surface, N-stage dynodes (N is an integer of 2 or more) for multiplying electrons emitted from the photoelectric surface, and an anode for collecting electrons multiplied by the dynodes. The anode has an electron collection surface that faces a secondary electron emission surface of the N-th stage dynode and at least partially extends along the secondary electron emission surface, and there is no electron passage hole on an electron path from the N-1th dynode to the N-th dynode.

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.

The invention provides a photomultiplier signal output charge distribution circuit, and belongs to the field of photomultiplier signal output. According to the invention, the technology that a plurality of capacitors are connected in parallel to carry out charge distribution is utilized, the anode output signal of the photomultiplier is distributed on two paths of output according to a required dynamic range, outputs in different dynamic ranges are naturally formed, and a subsequent readout electronics circuit can be matched. The circuit is simple in structure, high in reliability, good in voltage-resistant isolation performance, free of a peripheral control circuit and a feedback system, and suitable for occasions such as a space detector with high requirements for the size, weight and reliability of the circuit; according to the invention, the output linearity of the photomultiplier is maintained, the working voltage of each dynode of the photomultiplier is not influenced while the charges are distributed, and the recovery time of the photomultiplier is not influenced; output signals are of two-path same-direction models, a subsequent reading electronics circuit does not need to be additionally processed, and the photomultiplier is suitable for occasions needing two-path output of a single photomultiplier.

This photomultiplier tube comprises: a photoelectric surface; N stages of dynodes (where N is an integer of 2 or more) that multiply electrons emitted from the photoelectric surface; and an anode that collects the electrons multiplied by the dynodes. The mth stage dynode (where m is an integer that is not less than 2 and not more than N) is disposed opposite from the m-1th stage dynode. In the longitudinal direction of the dynodes, the width of the edge of mth stage dynode on the m-1th stage dynode side thereof is less than the width of the m-1th stage dynode. In the longitudinal direction, said edge of the mth stage dynode is contained inside the m-1th stage dynode.

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 belongs to the technical field of electron multipliers, and relates to a bowl-shaped dynode multiplication structure and an electron multiplier comprising the same. The dynode multiplication structure is integrally of a bowl-shaped structure and specifically comprises an A-type dynode located in the middle and a B-type dynode located on the periphery of the A-type dynode by a circle. The A-type dynode comprises a circular substrate, a cone-like body is arranged on the circular substrate, the B-type dynode comprises a fan-shaped cone, and secondary electron emission films are attached to the arc-shaped surface of the cone-like body and the arc-shaped inner surface of the fan-shaped cone. The curved surface of the cone-like body is a smooth arc-shaped curved surface or a curved surface consisting of three sections of inclined surfaces with different slopes; and the curved surface of the fan-shaped cone is a smooth arc-shaped curved surface or a curved surface consisting of three sections of inclined surfaces with different slopes. By adopting the bowl-shaped structure, the electron receiving rate of the first-stage dynode can be improved, and the gain of the electron multiplier can be improved; under the structure, electrons have a larger bombardable area, the loss of the secondary electron emission film is reduced, and the service life of the multiplier is prolonged.

An electron tube (1) is provided with: a photoelectric surface (3) that converts incident light into photoelectrons; a plurality of dynodes (11) and anodes (6); an insulating substrate (12) that holds the dynode (11) and the dynode (11) and the anode (6) in an electrically insulated state; and a case (2) that houses the dynode (11), the anode (6), and the insulating substrate (12). The insulating substrate (12) has: a base layer (21) that is made of a polycrystalline material and has electrical insulation properties; an electrically insulating intermediate layer (22) comprising an amorphous material; and a surface layer (23) comprising a carbon-containing material and having a lower electrical resistance than the intermediate layer (22).

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 embodiment relates to an electron multiplier or the like having a structure for achieving faster response characteristics than conventional technologies. The electron multiplier comprises at least a dynode unit, a tube socket, a coaxial cable, a conductive member, and a capacitor. The dynode unit includes a multistage dynode, an anode, and a pair of insulating support members. The exposed portion of the inner conductor, which forms part of one end of the coaxial cable, is introduced into the dynode unit together with the end of the outer conductor. This structure allows the capacitor to be positioned in the space between the dynode unit and the tube socket, and the exposed portion of the inner conductor to be fixed to the portion of the anode held between the pair of insulating support members.

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.

The present invention discloses a novel PMT gating variable gain system for a pulsed lidar. It includes a multi-pixel photon counter, a voltage dividing network, an AGC variable gain unit, a gating pulse unit, a DC high voltage network, and a PMT synchronous control unit. The multi-pixel photon counter converts the received optical signal into an electrical signal; the voltage dividing network preliminarily amplifies the electrical signal generated by the multi-pixel photon counter, one path enters the AGC variable gain unit, and the other path enters the gating pulse unit; the gating pulse unit controls the potential between the first dynode and the photocathode to remain closed before the gating pulse arrives, and the AGC variable gain unit controls the potential difference between the dynodes to achieve variable gain amplification of the circuit; it reaches the PMT synchronous control unit through the DC high voltage network to control the PMT to achieve the purpose of fast gating variable gain. The present invention can effectively reduce the error caused by echo noise and expand the dynamic range.

The present invention discloses an ion detection system and a detection method. The detection system includes: a quadrupole exit lens, a first deflection lens, a second deflection lens, a first dynode, and a second dynode. Among them, the quadrupole exit lens is configured to focus and output ions generated by a mass spectrometer; the first dynode is accommodated in a first insulating sleeve, and the second dynode is accommodated in a second insulating sleeve. Both the first insulating sleeve and the second insulating sleeve are provided with openings; the first deflection lens and the second deflection lens are symmetrically arranged on both sides of the exit of the quadrupole exit lens. By applying an electric field, the path of the ions output by the quadrupole exit lens is changed, so that positive ions deviate from the second deflection lens and pass through the opening to reach the first dynode, and negative ions deviate from the second deflection lens and pass through the opening to reach the second dynode. The present invention realizes simultaneous detection of positive and negative ions, and solves the problems of low detection efficiency and poor detection accuracy caused by voltage switching delay.

The utility model discloses a photomultiplier counting signal processing circuit and a photomultiplier counting device, and relates to the technical field of photomultipliers, the photomultiplier counting signal processing circuit comprises a first signal input end used for accessing an anode signal; the second signal input end is used for accessing a last-stage dynode signal; the signal amplification circuit is used for carrying out differential amplification on the photomultiplier anode signal and the last-stage dynode signal and then outputting a corresponding differential signal; the comparison shaping circuit is used for respectively accessing the differential signal and the comparison threshold signal, carrying out comparison shaping and then outputting a shaping signal; the counting circuit is used for counting the shaping signals; according to the technical scheme provided by the utility model, the problem of how to avoid the influence of power ripples on counting accuracy in counting signal processing of the photomultiplier is solved.

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 utility model discloses a photomultiplier voltage division circuit and a photomultiplier counting device, and relates to the technical field of photomultipliers, and the photomultiplier voltage division circuit comprises a voltage output circuit which comprises a first output end and a second output end and is used for outputting high-frequency AC voltage; the voltage doubling rectification voltage division circuit comprises a first input end, a second input end, a grounding end and N + 2 voltage division ends, the first input end is connected with the first output end, the second input end is connected with the second output end, the grounding end is grounded, the first voltage division end is connected with the focusing electrode, the last voltage division end is connected with the anode, and the other voltage division ends are connected with the N dynodes in a one-to-one correspondence mode; the voltage doubling rectification voltage division circuit is used for carrying out step-by-step voltage doubling rectification on the accessed high-frequency alternating-current voltage and outputting corresponding direct-current voltage to the N dynodes respectively; according to the technical scheme provided by the utility model, the problem of how to enable the photomultiplier to keep high counting rate under the condition of high input photon density is solved.