26 results about "Electron multiplier" patented technology

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.

An electron tube is provided in which electrons emitted from an electron emitting section can be reliably made to reach an electron multiplier section, and the electrons can be reliably multiplied in the electron multiplier section. [Solution] The electron tube (1) comprises an electron emitter (3) including a metasurface (32) that emits electrons in response to incidence of electromagnetic waves (W), an electron multiplier (4) that multiplies the electrons emitted from the electron emitter (3), and a first mesh electrode (5) arranged between the electron emitter (3) and the electron multiplier (4). The electron multiplier (4) has an electron incidence region (4a) onto which the electrons emitted from the electron emitter (3) are incident. The distance α between the metasurface (32) and the electron incidence region (4a) is smaller than the width β of the electron incidence region (4a).

The embodiment of the invention provides a wide dynamic range ion pulse threshold adaptive counting method and circuit, and the method comprises the steps: a first end of an electron multiplier is connected with an ion signal, a second end is connected with an input end of an amplification circuit, an output end is connected with a first end of a baseline extraction module, and a second end is connected with a first end of a baseline smoothing module; the second end is connected with the input end of the comparison circuit and the output end is connected with the counting circuit; the electron multiplier is used for converting the ion signal into a current pulse; the amplifying circuit is used for converting the current pulse into a voltage pulse; the baseline extraction module is used for extracting a voltage pulse baseline to obtain a baseline signal; the baseline smoothing module is used for smoothing the baseline signal to obtain a smoothed signal; the comparison circuit is used for dynamically determining a self-adaptive threshold value based on the smooth signal, comparing the voltage pulse with the self-adaptive threshold value and outputting a comparison signal; and the counting circuit is used for pulse counting to obtain the number of target pulses. Therefore, the counting accuracy and the counting upper limit are improved.

The invention provides a hierarchical control method and device for a residual gas analyzer and a medium, and the method comprises the steps: receiving a starting instruction sent by machine station equipment, and starting an ion source when the local vacuum degree is smaller than a first preset threshold value; when the total voltage is smaller than a second preset threshold value, an electron multiplier power supply is started; when the local vacuum degree and the total pressure are smaller than a third preset threshold value, a mass spectrometer power supply is started; receiving a vacuum breaking instruction sent by the station equipment, and disconnecting a functional module power supply of the residual gas analyzer; and receiving a power-off instruction sent by the station equipment, and when the local vacuum degree and the total pressure are greater than or equal to a second preset threshold value, cutting off the power supply of the electron multiplier, and when the local vacuum degree and the total pressure are greater than or equal to a first preset threshold value, disconnecting the ion source and the mass spectrometer power supply in sequence. The problem of hardware damage caused by out-of-control vacuum degree of the residual gas analyzer is solved through vacuum degree pre-judgment, graded protection and intelligent collaborative protection methods.

The present application relates to the field of pharmaceutical analysis, and more particularly to a method for simultaneously determining the contents of multiple components in Yinhu Ganmao Powder based on GC-MS technology, which comprises a method for simultaneously determining the contents of multiple components in Yinhu Ganmao Powder or volatile oil. The method comprises the following steps: (1) performing GC analysis on the extract of Yinhu Ganmao Powder or volatile oil; (2) performing mass spectrometry identification using a mass spectrometry library, with the mass spectrometry conditions being: ion source is electron impact ionization (EI), energy is 70 eV, ion source temperature is 200 DEG C, interface temperature is 250 DEG C, full scan mode is m / z 45-500, electron multiplier voltage is 1.5 kV, and collision gas is argon (99.99%). The present application establishes a method for simultaneously determining the contents of multiple components in Yinhu Ganmao Powder or volatile oil based on GC-MS technology, wherein more than 50 compounds are identified in the volatile oil of Yinhu Ganmao Powder, and more than 25 compounds are identified in the n-hexane extract of the powder.

The invention belongs to the field of mass spectrometry instruments, particularly relates to an ion receiving device, and aims to solve the problem of signal crosstalk among multiple channels of a combined receiver. The ion receiving device provided by the invention comprises a receiver body, and a signal detection cup unit, a slit sheet, a suppression gate unit, a Faraday cup unit and an electron multiplier unit which are mounted on the receiver body, the slit piece, the suppression gate unit and the Faraday cup unit are arranged along a first direction, and an ion beam sequentially passes through the slit piece, the receiver body and the suppression gate unit and then enters the Faraday cup unit; the signal detection cup unit, the Faraday cup unit and the electron multiplier unit are arranged at intervals along a second direction, and the second direction is perpendicular to the first direction. According to the ion receiving device provided by the invention, the signal detection cup unit, the Faraday cup unit and the electron multiplier unit are arranged at intervals along the direction perpendicular to the incident direction of the ion beam, so that signal crosstalk among channels is avoided.

The application provides an electronic detector and an electronic detection system. The electronic detector comprises: a Faraday cage for collecting secondary electrons; an electron multiplier fixed to a shielding outer cylinder, for performing primary amplification of the secondary electrons based on a first voltage at an input end of the electron multiplier and a second voltage at an output end of the electron multiplier; a power supply ring connected to the input end of the electron multiplier and the output end of the electron multiplier respectively, for providing the first voltage to the input end of the electron multiplier and the second voltage to the output end of the electron multiplier; a semiconductor detector fixed to the shielding outer cylinder, for applying a third voltage and a bias voltage to the secondary electrons to convert the secondary electrons into a current signal after performing secondary amplification; an amplifier circuit connected to the semiconductor detector, for converting the current signal into a voltage signal; and a signal amplification processing circuit, for converting an image signal from the voltage signal after amplification, so that the electronic detection efficiency can be improved and the image signal-to-noise ratio can be enhanced.

The invention discloses an ultraviolet light electron spectrometer which comprises a vacuum cavity and a magnetic shielding layer. A barrel lens type electron energy analyzer is arranged in the magnetic shielding layer, and the barrel lens type electron energy analyzer comprises a lens system and an electron multiplication detector; the lens system comprises two coaxially arranged annular lenses, a uniform annular channel is formed between the two annular lenses, and an ultraviolet light beam incidence channel is formed in the middle of the annular lens on the inner side; the electron multiplication detector is arranged on the upper portion of the inner side face of the inner side annular lens. The ultraviolet light source is arranged at the top of the ultraviolet light beam incidence channel; the sample table is arranged at the bottom of the ultraviolet light beam incidence channel and is arranged opposite to the ultraviolet light source emitting end; according to the invention, the ultraviolet light beam is combined with the barrel lens type electron energy analyzer, so that the miniaturization of the ultraviolet light electron energy spectrometer is realized.

The CEM and ion detector of the present embodiment has a configuration for achieving ion detection with higher sensitivity than the prior art. The channel-type electron multiplier has at least a channel body, an input-side conductive layer, an output-side conductive layer, and an electrode. The channel body contains a channel having a tapered opening portion provided on the input side, and a resistance layer and an electron emission layer formed on the inner wall surface of the channel. The input-side conductive layer is provided on the input end surface of the channel body and a part thereof extends within the tapered opening portion. The output-side conductive layer is provided on the output end surface of the tapered opening portion. The electrode has one or more openings through which charged particles pass, and is disposed on the opposite side of the output end surface with respect to the input end surface. The electrode and the input-side conductive layer are set to the same potential by excluding the influence of an external electric field within the tapered opening portion.

The invention discloses a high-helix multichannel electron multiplier and a preparation method thereof, which are suitable for weak signal detection systems in high-end analytical instruments such as an Auger electron spectrometer (AES), an X-ray photoelectron spectrometer (XPS), a scanning electron microscope (SEM), a mass spectrometer and the like so as to meet the urgent requirements of the high-end analytical instruments on detectors with high sensitivity, low noise and long service life.

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.

The invention discloses an electron two-dimensional spin detector and application thereof. The electron two-dimensional spin detector comprises a high-transmittance metal net, an electron spin screening film, an electron multiplier and an electron detector which are sequentially arranged in the electron movement direction. Magnetizing devices are arranged around the electron spin screening film in the circumferential direction in an array mode, and positive and negative polarization in multiple directions is achieved. The high-transmittance metal net, the electron spin screening film and the electron multiplier are respectively connected with a voltage source, the voltage is changed, and the voltage difference between the high-transmittance metal net and the electron spin screening film is changed. The electron two-dimensional spin detector designed by the invention is simple in structure, does not need a complex process of coating or surface treatment, can directly detect two-dimensional spin electrons, can be combined with a hemispherical energy analyzer, a time-flight electron energy analyzer and other electron energy analyzers, and meets more measurement scenes.

To provide an electron tube that can appropriately make electromagnetic waves having a predetermined electric field oscillation direction incident on an electron emission section and can appropriately multiply electrons emitted from the electron emission section in response to the incidence of the electromagnetic waves having the predetermined electric field oscillation direction. [Solution] The electron tube (1) comprises an electron emitter (3) including a metasurface (32) that emits electrons in response to incidence of an electromagnetic wave (W) having a predetermined electric field oscillation direction (V), an electron multiplier (4) that multiplies the electrons emitted from the electron emitter (3), and a first mesh electrode (5) arranged between the electron emitter (3) and the electron multiplier (4). The first mesh electrode (5) includes a plurality of wires (52) that define a plurality of openings aligned in a first direction (D1) parallel to the electric field oscillation direction (V). When viewed from the propagation direction (T) of the electromagnetic wave (W), each of the plurality of openings has an elongated shape whose longitudinal direction is a second direction (D2) that intersects with the first direction (D1) at an angle of 45 degrees or more.

An electron tube capable of improving resistance to vibration or impact is provided. [Solution] The electron tube 1 comprises a housing 2 having a window 21a that transmits electromagnetic waves W, an electron emitter 3 that is disposed within the housing 2 facing the window 21a and includes a metasurface 32 that emits electrons on the side opposite the window 21a in response to the incidence of the electromagnetic waves W, and an electron multiplier 4 that is disposed within the housing 2 on the side opposite the window 21a with respect to the electron emitter 3 and multiplies the electrons emitted from the electron emitter 3. The electron multiplier 4 is fixed to the housing 2. The electron emitter 3 is fixed to the electron multiplier 4.

This invention belongs to the field of mass spectrometry analysis instruments, specifically relating to an ion receiving device designed to solve the signal crosstalk problem between multiple channels of a combined receiver. The ion receiving device provided by this invention includes a receiver body and a signal detection cup unit, a slit, a suppression grid unit, a Faraday cup unit, and an electron multiplier unit mounted on the receiver body. The slit, suppression grid, and Faraday cup units are arranged along a first direction, and the ion beam sequentially passes through the slit, the receiver body, and the suppression grid unit before entering the Faraday cup unit. The signal detection cup unit, Faraday cup unit, and electron multiplier unit are arranged at intervals along a second direction, which is perpendicular to the first direction. By arranging the signal detection cup unit, Faraday cup unit, and electron multiplier unit at intervals along a direction perpendicular to the ion beam incident direction, the ion receiving device provided by this invention avoids signal crosstalk between channels.

The application provides a background signal processing circuit and method for a quadrupole mass spectrometer, which comprises a pre-signal processing circuit and a data acquisition circuit, the pre-signal processing circuit comprises an amplification circuit, a fast discrimination circuit, a pulse shaping circuit and a differential output circuit connected in series, the amplification circuit is connected with an electron multiplier, and weak current pulse signals output by the electron multiplier are input to the amplification circuit; the data acquisition circuit comprises an FPGA core circuit and a pulse receiving circuit, a network port communication circuit, a quadrupole power voltage control circuit and an SPI interface circuit connected with the FPGA core circuit respectively, the differential output circuit is connected with the pulse receiving circuit, and the SPI interface circuit is connected with the fast discrimination circuit. By improving the hardware circuit structure, the application can automatically filter various noise signals in front of pulse counting, ensure the accuracy of pulse counting, and solve many problems caused by background signal interference in mass spectrum.

The invention mainly relates to the technical field of X-ray tubes, and provides a time-resolved pulse X-ray tube which mainly comprises a time-resolved pulse light source, an X-ray tube sleeve, a transparent glass window, an electron multiplier, a photocathode material, a bias power supply, a high-voltage power supply, an electron focusing lens, an X-ray target material and a beryllium window. The pulse light source excites the photocathode material to generate photoelectrons, the photoelectrons are multiplied in the electron multiplier under the action of the bias electric field, and the multiplied electrons are focused into electron beam spots smaller than 1 mm under the action of the high-voltage electric field and the electron focusing lens to bombard the anode target of the X-ray tube at a high speed. Therefore, time-resolved pulse X-rays are generated. The pulse X-ray tube has a very important application prospect in X-ray dynamic imaging.

The application discloses a kind of open hole type repeller and electron multiplier for mass spectrometer, and open hole type repeller includes repeller substrate, repeller substrate is by sequentially connected and not coplanar multiple plane, present recessed structure;Repeller substrate both sides are provided with one side baffle, by the electric field force of side baffle to the electron moving to two sides, so that electron is gathered to repeller central position;Along the direction of electron propagation, the first substrate plane of repeller substrate is provided with through-hole;The inner side surface of repeller substrate and two side baffles are covered with secondary electron emission film.The application can make the originally intercepted electron by first substrate plane pass through through-hole and be incident to the inner surface of subsequent repeller, so that more secondary electrons are generated in subsequent repeller, and metal grid is arranged at the opening of repeller, and the height of the side baffle of repeller is adjusted, to focus electron and optimize the transmission trajectory of electron between repellers, which significantly improves the gain.

The invention relates to a mass spectrometry technology, and particularly provides an electron multiplier, a mass spectrometry system and a mass spectrometry method, the electron multiplier comprises a multi-stage dynode, a collector and a power supply, and the power supply applies voltage to the dynode and the collector; the power supply is connected with the voltage division circuit, and the voltage division circuit is connected with the third dynode to the Nth dynode; the switching unit is used for switching the working mode of the voltage division circuit, the voltage division circuit applies positive bias voltage to the third-stage dynode to the Nth-stage dynode in the detection mode, and the voltage applied to the third-stage dynode to the Nth-stage dynode is the same in the cleaning mode. The cleaning device has the advantages of good cleaning effect, convenience and the like.

A Fourier Transform electrostatic linear ion trap (ELIT) is disclosed with an electron multiplier detector comprising one of a microchannel plate and a channel electron multiplier. An (ELIT) is provided comprising a central axis along which ions travel; an image current detector disposed at least partially around the central axis of the ELIT; and an electron multiplier detector arranged in an opening of the image current detector, the electron multiplier detector being operable to receive ions deflected from the central axis. The electron multiplier detector may have a front surface that is perpendicular to the central axis of the ELIT. The electron multiplier detector may comprise two separate elements at non-normal angles to the central axis of the ELIT. The image current detector may comprise a cylinder with the opening on one side in which the electron multiplier detector is arranged, a U-shape, or a half-tube detector.

The object is to provide an electron tube and an electron tube device that can appropriately multiply electrons emitted from a metasurface in response to the incidence of electromagnetic waves. The electron tube 1 includes an electron emitter 3 including a metasurface that emits electrons in response to incidence of electromagnetic waves W, an electron multiplier 4 that multiplies the electrons emitted from the electron emitter 3, and a second mesh electrode 6 disposed between the electron emitter 3 and the electron multiplier 4. The potential of the second mesh electrode 6 is set to a negative value when the potential of the metasurface of the electron emitter 3 is used as a reference.

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 invention relates to the technical field of electronic detection and signal amplification, in particular to a high-performance multi-channel arc channel type electron multiplier, which comprises an electronic input end used for receiving and focusing incident particles; the partition area is used for establishing a potential gradient; the alloy coating electrodes are respectively arranged at the input end and the output end of the electron multiplier and are used for applying working voltage; the multi-channel arc-shaped array structure comprises a plurality of arc-shaped channels which take the center of the section of the electron multiplication area tube body as the circle center and are uniformly arranged on the same circumference, and the arc-shaped channels are parallel to one another; the voltage division area is used for stabilizing electric field distribution in the channel; compared with the prior art, the high-gain and high-resolution collaborative improvement is realized, the high-temperature-resistant stability is excellent, the working life is ultra-long, meanwhile, low noise, quick response and efficient signal detection are achieved, the performance reaches the import standard, and a reliable core component is provided for localization of high-end instruments.

A terahertz wave interferometric measurement device comprising: an optical pulse train generator outputting a periodic first optical pulse train having a first repetition frequency and a periodic second optical pulse train having a second repetition frequency lower than the first repetition frequency; a first converter converting the first optical pulse train into a first terahertz wave; a second converter converting the second optical pulse train into a second terahertz wave; a wave-combining optical system combining the first terahertz wave and the second terahertz wave to generate a third terahertz wave; a trigger generator generating a trigger signal indicating a timing of detecting the third terahertz wave; and a detector having an electron emitter for receiving the third terahertz wave and emitting electrons and an electron multiplier for receiving the electrons and emitting secondary electrons, and detecting the third terahertz wave at the timing indicated by the trigger signal.

The invention discloses a measurement and control system for electron multiplier acceleration testing, and belongs to the field of electron multiplier service life testing. The system comprises a vacuum system, an electronic gun servo module, a program control high-voltage source, an electrometer, a universal meter and a computer measurement and control program. The system adopts a modular design, and the vacuum system provides an electron multiplier test vacuum degree and an electron gun working vacuum degree; the electron gun servo module comprises an electron gun current source and an electron gun potential servo module and is used for accurately controlling the size of an incident electron beam current of the electron multiplier; the program-controlled high-voltage source can be controlled by a computer program and provides working voltage for the multiplier, and the multiplier is externally connected with a divider resistor port and a current collecting port. The electrometer and the universal meter are used for collecting data. The computer control software is written by MATLAB language and has a graphical interface. After the output of the current source and the potential of the electron gun are fixed, a control program controls the output voltage of the program-controlled high-voltage source through a serial port by collecting the output current of the multiplier, so that the multiplier is ensured to work in a fixed gain mode. The incident current is controlled to be at a relatively large value, and the total output charge number when the multiplier fails can be obtained through an acceleration test in a fixed gain mode.

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.