CN116825600A - Photomultiplier tube, manufacturing method thereof and detector - Google Patents

Abstract

The application provides a photomultiplier, a manufacturing method thereof and a detector, wherein the photomultiplier comprises: a photocathode for receiving photons and emitting photoelectrons based on the received photons; the photomultiplier is positioned at the downstream of the photocathode and comprises an electron sharing structure, and is used for receiving the photoelectrons and carrying out sharing and multiplication on the photoelectrons through the electron sharing structure; and an anode for collecting photoelectrons multiplied via the photomultiplier system and outputting an anode current based on the collected photoelectrons. The scheme of the application improves the pulse width response range of the photomultiplier and the linear current of the photomultiplier.

Description

Photomultiplier tube, manufacturing method thereof and detector

Technical Field

The application relates to the field of light detection, in particular to a photomultiplier, a manufacturing method thereof and a detector.

Background

Photomultiplier tubes are vacuum electronic devices that convert weak light signals into electrical signals, typically combined with scintillators into radiation detection devices. Currently, photomultiplier tubes are widely used in the fields of optical analysis instruments, medical equipment, environmental monitoring, industrial inspection, high-energy physics and the like.

The basic working principle of the photomultiplier is that light is converted into photoelectrons after entering a cathode of the photomultiplier, then the photoelectrons enter a multiplication system of the photomultiplier to be multiplied, and finally the multiplied photoelectrons are collected through an anode of the photomultiplier to form anode current output.

In theory, the output current of the anode of the photomultiplier tube and the luminous flux incident on the cathode show linear photoelectric characteristics, but most photomultiplier tubes have linear deviations when receiving stronger light incidence in practical application. The maximum current that a photomultiplier tube can output within an allowable linear deviation error is commonly referred to as a linear current. Most of the prior photomultiplier has a narrow dynamic response range, and the linear current of the photomultiplier can only be below 100 mA. The linear current of a very small fraction of photomultiplier tubes can reach 200mA, but is limited to narrow pulse width signals below 50 ns. For a wider pulse width signal, such as a 500ns pulse width signal, saturation occurs and the output current of the photomultiplier tube no longer varies with the input.

Disclosure of Invention

The application aims to provide a photomultiplier, a manufacturing method thereof and a detector, so as to solve the problems of small linear current and narrower pulse width response of the existing photomultiplier.

According to an aspect of the present application, there is provided a photomultiplier including: a photocathode for receiving photons and emitting photoelectrons based on the received photons; the photomultiplier is positioned at the downstream of the photocathode and comprises an electron sharing structure, and is used for receiving the photoelectrons and carrying out sharing and multiplication on the photoelectrons through the electron sharing structure; and an anode for collecting photoelectrons multiplied via the photomultiplier system and outputting an anode current based on the collected photoelectrons.

According to some embodiments, the electron apportionment structure is disposed about a target axis;

the target axis coincides with or is parallel to the central axis of the photomultiplier tube.

According to some embodiments, the photomultiplier system includes a plurality of first photomultiplier subsystems disposed in parallel with each other and together comprising an electron-sharing structure.

According to some embodiments, the photomultiplier system includes a second photomultiplier subsystem, the second photomultiplier subsystem being annular, the second photomultiplier subsystem being integral as an electron-sharing structure.

According to some embodiments, each of the first photomultiplier subsystems comprises a multi-stage tiled dynode.

According to some embodiments, a plurality of tile-shaped dynodes of the same stage are arranged in parallel with each other.

According to some embodiments, the second photomultiplier subsystem includes a multi-stage annular dynode.

According to some embodiments, the ring dynode comprises a ring dynode, a cylindrical dynode, a conical dynode, and/or a ring dynode surrounded by a polygonal dynode.

According to some embodiments, the ring dynode includes a ring dynode surrounded by a plurality of polygon dynodes, and each two adjacent polygon dynodes of the same stage are connected to each other.

According to some embodiments, the photomultiplier tube is configured to respond to a 500 nanosecond to 10 microsecond pulse width light signal.

According to an aspect of the present application, a method of manufacturing a photomultiplier tube is provided for manufacturing a photomultiplier tube as described above.

According to an aspect of the application, a detector is presented, characterized by comprising a photomultiplier as described above.

According to the scheme, the pulse width response range of the photomultiplier is improved, and the linear current of the photomultiplier is improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application as claimed.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the description of the embodiments will be briefly described below. The above and other objects, features and advantages of the present application will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.

Fig. 1 shows a schematic diagram of a prior art photomultiplier tube.

Fig. 2a shows an electron reflection diagram of a photomultiplier tube.

Fig. 2b shows an electron cloud schematic of a photomultiplier tube.

Fig. 3 shows a block diagram of a photomultiplier provided according to an exemplary embodiment of the present application.

Fig. 4 shows a schematic diagram of a photomultiplier provided according to an exemplary embodiment of the present application.

Fig. 5a shows a schematic top view of a photomultiplier system according to an exemplary embodiment of the present application, including three evenly distributed photomultiplier subsystems.

Fig. 5b shows a schematic top view of a photomultiplier system according to an exemplary embodiment of the present application, including four evenly distributed photomultiplier subsystems.

Fig. 5c shows a schematic top view of a photomultiplier system according to an exemplary embodiment of the present application including five evenly distributed photomultiplier subsystems.

Fig. 6 shows a schematic diagram of a dead space position of a photomultiplier provided according to an exemplary embodiment of the present application.

Fig. 7 shows a schematic view of an occlusion part of a photomultiplier provided according to an exemplary embodiment of the present application.

Fig. 8a shows a schematic top view of a trilateral ring multiplier system provided according to an example embodiment of the present application.

Fig. 8b shows a schematic top view of a quadrilateral ring multiplication system provided according to an example embodiment of the application.

Fig. 8c shows a schematic top view of a pentagonal ring multiplication system provided according to an example embodiment of the present application.

Fig. 9 shows a schematic top view of a circular ring photomultiplier system provided according to an exemplary embodiment of the present application.

Fig. 10 shows a flowchart of a method for manufacturing a photomultiplier according to an exemplary embodiment of the present application.

Fig. 11 shows a linear current contrast schematic of a photomultiplier tube with different multiplication systems provided in accordance with an embodiment of the present application.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same drawing figures in the drawings show the same or similar parts, and thus a repetitive description thereof will be omitted.

The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the disclosed aspects may be practiced without one or more of the specific details, or with other methods, components, materials, devices, operations, etc. In these instances, well-known structures, methods, devices, implementations, materials, or operations are not shown or described in detail.

The flow diagrams depicted in the figures are exemplary only, and do not necessarily include all of the elements and operations/steps, nor must they be performed in the order described. For example, some operations/steps may be decomposed, and some operations/steps may be combined or partially combined, so that the order of actual execution may be changed according to actual situations.

The terms first, second and the like in the description and in the claims and in the above-described figures are used for distinguishing between different objects and not necessarily for describing a sequential or chronological order. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed steps or elements but may include other steps or elements not listed or inherent to such process, method, article, or apparatus.

Fig. 1 shows a schematic diagram of a prior art photomultiplier, in which, in the photomultiplier shown in fig. 1, photons strike a photocathode 2 through an entrance window 1, the photocathode 2 emits photoelectrons, the photoelectrons are multiplied by multiple stages of a multiplication system 3 to obtain more photoelectrons, and finally the photoelectrons are output through an anode.

For example, the photocathode 2 emits k photoelectrons in total, and the number of electrons becomes M after the k photoelectrons are multiplied by the 1 st to n-1 st dynodes in front of the multiplier system 3. Theoretically, the M photoelectrons would continue to multiply into the next stage dynode, the nth stage dynode (DYn), as shown in FIG. 2 a. But when M reaches a certain amount, electrons form an electron cloud above the DYn surface. The formed electron cloud can prevent the incident electrons from reaching the surface of DYn and prevent electron multiplication, as shown in fig. 2b, so that the current output by the photomultiplier tube is delayed, that is, the output current of the photomultiplier tube is not enhanced in a linear relationship with the enhancement of the incident light, and linear deviation occurs. The linear current of the existing photomultiplier is small and basically below 100mA, and very few photomultiplier can reach 200mA and is limited to narrow pulse width signals below 50 ns. The width of the pulse width signal determines the size of the photon cluster of the incident light, the wider the pulse width signal is, the larger the incident photon cluster is, the more photons are received by the photocathode 2, the more photoelectrons are emitted, the more linear deviation phenomenon is easy to occur, and even the saturation phenomenon occurs, namely, the output current of the photomultiplier is not changed along with the input. The existing photomultiplier has saturation phenomenon when the pulse width is 500ns or more.

The embodiment of the application provides a photomultiplier comprising an electron sharing structure, the performance of the whole photomultiplier is improved through the electron sharing structure, the number of electron aggregation of each stage of dynode can be reduced under the same pulse width signal, and the probability of electron cloud occurrence is reduced, so that the linear current and dynamic pulse width response range of the photomultiplier are improved, and the problems of small linear current and narrow pulse width response of the existing photomultiplier are solved.

Specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

Fig. 3 shows a block diagram of a photomultiplier tube according to an exemplary embodiment of the present application, the photomultiplier tube shown in fig. 3 including a photocathode 301, a photomultiplier system 303, and an anode 305. Wherein the photocathode 301 is configured to receive photons and emit photoelectrons based on the received photons; a photomultiplier 303 is located downstream of the photocathode 301 and includes an electron-splitting structure 3031, and the photomultiplier 303 is configured to receive photoelectrons and split and multiply the photoelectrons by the electron-splitting structure 3031; the anode 305 is for collecting photoelectrons multiplied via the photomultiplier system 303 and outputting an anode current based on the collected photoelectrons.

The electron splitting structure 3031 refers to a structure that can split and then re-multiply incident photoelectrons by changing the number and/or shape of multiplication systems, and may be, for example, a structure having an electron splitting function obtained by increasing the number of original multiplication systems or a structure having an electron splitting function in which original tile-shaped multiplication systems are designed in a ring shape, as will be described in detail below. Thus, assuming that the number of photoelectrons received by the original multiplier system is K1, the number of electrons accumulated to reach the n-th dynode reaches M1, and the photomultiplier tube is linearly deviated. However, with the photomultiplier having the electron-splitting structure 3031 of the present application, assuming that the number of photoelectrons incident to the multiplier system 303 is K1, the K1 photoelectrons are split and multiplied by the electron-splitting function of the electron-splitting structure 3031, the number of electrons collected to the n-th dynode will not reach M1, no linear deviation will occur, and when the number of incident photoelectrons continues to increase sufficiently, the linear current will be obviously improved, and the response pulse width range will be improved accordingly.

According to the embodiment of the application, the electron splitting structure 3031 is added in the photomultiplier system 303, so that the generation probability of electron cloud is reduced, and the pulse width response range of the photomultiplier and the linear current of the photomultiplier are improved.

The photomultiplier provided by the embodiment of the application can be used for responding to light signals with pulse width of 500 nanoseconds to 10 microseconds, and the linear current can reach 200mA to 1000mA, even more than 1000mA.

According to some embodiments of the application, electron-splitting structure 3031 in photomultiplier system 303 is disposed about a target axis; the target axis coincides with or is parallel to the central axis of the photomultiplier tube.

At this time, the electron distribution structure 3031 is disposed around the target axis which coincides with or is parallel to the central axis of the photomultiplier, so that the electron distribution structure 3031 surrounds and distributes the photoelectrons emitted from the upstream photocathode 301 in the radial direction of the photomultiplier, and the distributed structure can be used to realize the distribution effect.

Preferably, the target axis coincides with the central axis of the photomultiplier tube. At this time, the electron splitting structure 3031 is disposed around the target axis, i.e., the central axis of the photomultiplier, the electron splitting structure 3031 is aligned to the photocathode 301, and the photoelectrons emitted from the photocathode 301 can be incident into the electron splitting structure 3031 in a relatively short path to achieve splitting and multiplication, so that the effect of improving the response speed is achieved on the basis of improving the linear current and pulse width response range of the photomultiplier.

However, in actual operation, due to a machining process or the like, there is a possibility that a deviation occurs such that the target axis is parallel to the central axis of the photomultiplier, but not coincident with, but in the vicinity of the central axis, and the electron split structure 3031 is disposed around the axis in the vicinity of the center of the photomultiplier. In this case, although the electron split structure 3031 is deviated, the electron split structure 3031 is also basically aligned to the photocathode 301, and the response speed can be improved on the basis of improving the linear current and the pulse width response range of the photomultiplier.

The target axis may be parallel to the central axis of the photomultiplier, but not near the central axis, and the electron-distributing structure 3031 may be disposed eccentrically. In this case, although the electron split structure 3031 is not aligned with the photocathode 301, photoelectrons emitted from the photocathode 301 can be injected into the electron split structure 3031 to split and multiply electrons, thereby achieving the effect of increasing the linear current and the pulse width response range of the photomultiplier, but the response speed is reduced.

According to some embodiments of the application, the electronic split structure 3031 may also be arranged not in a manner about the target axis, but in a row or column or matrix (only for schemes that change the number of multiplication systems). Generally, the photomultiplier tubes are columnar, and the photomultiplier tubes are arranged in a manner around the target axis to better adapt to the shape of the photomultiplier tubes and achieve better electron sharing effect, but other special-shaped photomultiplier tubes are not excluded, and the electron sharing structure 3031 can be adaptively deformed, such as arranged in a row or a column or a matrix.

According to some embodiments of the present application, the photomultiplier system 303 may include a plurality of first photomultiplier subsystems 3032, the plurality of first photomultiplier subsystems 3032 being disposed in parallel with one another and together forming an electron-sharing structure 3031.

At this time, compared with the prior art, the probability of generating electron cloud by each first photomultiplier subsystem 3032 is reduced by utilizing a plurality of first photomultiplier subsystems 3032 to split incident photoelectrons, thereby improving the pulse width response range of the photomultiplier and the linear current of the photomultiplier.

Among them, the photomultiplier generally includes a plurality of stages of dynodes, and in order to ensure that the plurality of stages of dynodes operate normally, a proper voltage gradient distribution, that is, inter-electrode voltage distribution, is required between each stage of dynodes. When the photomultiplier 303 is changed to a combination of multiple first photomultiplier 3032, a proper voltage gradient distribution is ensured between the dynodes under each first photomultiplier 3032, and the voltages between the dynodes under the same photomultiplier need to be kept consistent, so that the multiple first photomultiplier 3032 are arranged in parallel.

In particular embodiments, each first photomultiplier subsystem 3032 includes a plurality of tile-shaped dynodes, and each first photomultiplier subsystem 3032 includes the same number of dynodes, and the plurality of tile-shaped dynodes of the same level are arranged in parallel with each other. At this time, each first photomultiplier subsystem 3032 is composed of a plurality of tile-shaped dynodes, realizes multi-stage multiplication, and each stage has dynodes under a plurality of dynodes for electron sharing, reduces the probability of electron cloud occurrence of each stage dynode, improves the linear current and dynamic pulse width response range of the photomultiplier, and ensures that the same potential exists between the same stage dynodes by enabling the same stage dynodes to be arranged in parallel with each other, so that the interelectrode voltages of the plurality of dynodes are kept consistent, and the normal operation of the multi-stage dynodes of the plurality of dynodes is realized.

Of course, the first photomultiplier subsystem 3032 may also employ dynodes of other shapes, such as triangular, trapezoidal, and other polygonal shapes, not specifically illustrated herein.

In particular embodiments, the plurality of first photomultiplier subsystems 3032 are disposed next to one another about the target axis. In other embodiments, the plurality of first photomultiplier subsystems 3032 are disposed apart from one another about the target axis. Relatively, the arrangement next to each other is more space-saving.

Fig. 4 is a schematic diagram of a photomultiplier according to an exemplary embodiment of the present application, where the photomultiplier shown in fig. 4 includes three first photomultiplier subsystems 3032, and the three first photomultiplier subsystems 3032 are connected in parallel to each other, so as to split the number of electrons reaching the surface of each stage of dynode as much as possible, reduce the occurrence probability of electron cloud, ensure that photoelectrons can be normally multiplied, and improve the linear current.

As shown in fig. 4, the number of electrons received by each stage dynode surface of each first photomultiplier subsystem 3032 is about one third of that of the photomultiplier tube shown in fig. 1, thereby reducing the probability of electron cloud occurrence.

For example, assuming that the photocathode 301 emits k photoelectrons in total, the k photoelectrons are split at the first-stage dynode of the plurality of dynodes, the number of electrons reaching the surface of each of the 1 st-stage dynodes Dy1 is about k/3, and the number of electrons reaching the surface of each of the DYn after multiplication by the 1 st to n-1 st-stage dynodes is about M/3. At this time, each stage of dynode is allocated to the photo-electrons by means of 3 dynode combinations, which is equivalent to that the carrying capacity of each stage of dynode to the electrons is enlarged by 3 times, so that the output linear current value is improved by multiple times.

It should be noted that, fig. 4 is an example of a photomultiplier tube including 3 photomultiplier subsystems, but it will be understood by those skilled in the art that, in order to obtain a better photoelectron splitting effect, the photomultiplier tube according to the embodiment of the present application may also include more than 3 photomultiplier subsystems, or may include 2 photomultiplier subsystems in a scenario where the linear current requirement is not so high, which is not repeated herein.

To achieve better splitting, according to some embodiments of the present application, the plurality of first photomultiplier subsystems 3032 may be uniformly distributed about the target axis (see above for the target axis), and each first photomultiplier subsystem 3032 corresponds to one splitting area of photocathode 301, such that photoelectrons emitted by photocathode 301 are respectively incident on the plurality of first photomultiplier subsystems 3032, thereby achieving better electron splitting.

Of course, the plurality of first photomultiplier subsystems 3032 may not be uniformly distributed, and in this case, the electron sharing function can be realized, so as to achieve the effect of improving the linear current and the pulse width response range of the photomultiplier.

Fig. 5a, 5b and 5c show a schematic top view of a uniform distribution of a plurality of first photomultiplier subsystems 3032 according to an exemplary embodiment of the present application, wherein the photomultiplier shown in fig. 5a includes three uniformly distributed first photomultiplier subsystems 3032, the photomultiplier shown in fig. 5b includes four uniformly distributed first photomultiplier subsystems 3032, and the photomultiplier shown in fig. 5c includes five uniformly distributed first photomultiplier subsystems 3032. Based on the photomultiplier shown in fig. 5 a-5 c, the incident photoelectrons can be shared by using a plurality of first photomultiplier subsystems 3032, so that the number of the photoelectrons received by the surface of each stage of dynode is about one third, one fourth or one fifth of that of the traditional structure, which is equivalent to that the carrying capacity of each stage of dynode to the photoelectrons is enlarged by 3 times, 4 times or 5 times, and correspondingly, the linear current value is also improved by 3 times, 4 times or 5 times. Therefore, the occurrence probability of the electron cloud is weakened, and the output linear current value is improved in a multiplied mode.

The first photomultiplier subsystem 3032 shown in fig. 5a, 5b or 5c is composed of a plurality of dynodes, and although the combined structure can multiply the carrying capacity of each stage of dynode electrons, the inventor of the present application finds that a dead space 4 exists between two adjacent first photomultiplier subsystems 3032, as shown in fig. 6. Since the dead space corresponds to a partial region of the photocathode, photoelectrons incident to the partial space cannot be multiplied. For further optimization, a ring photomultiplier is proposed. The following description is made.

According to further embodiments of the present application, the photomultiplier system includes a second photomultiplier subsystem 3033, the second photomultiplier subsystem 3033 being annular, the second photomultiplier subsystem 3033 being integral as an electron-sharing structure 3031. By the annular second photomultiplier system 3033, dead space can be eliminated, further expanding the carrying capacity of the multiplier system for electrons, thereby further increasing the linear current and pulse width response range of the photomultiplier.

According to an embodiment of the application, the second photomultiplier subsystem 3033 may include a multi-stage ring dynode. Thus each dynode avoids the problem of dead space.

According to some embodiments of the application, the ring dynode may include a ring dynode, a cylindrical dynode, a conical dynode, and/or a ring dynode surrounded by a polygonal dynode. The following is a detailed description.

The structure of the conventional dynode system is shown in fig. 7, in which each stage of dynode is fixed on a base plate 6 by lugs 5 on both sides, and according to some embodiments of the present application, the base plate 6 on the side of the dynode is removed, and adjacent dynodes of corresponding stages are connected to each other, so that a polygonal ring-shaped internally and externally matched dynode structure, that is, a ring-shaped dynode surrounded by polygonal dynodes, is formed. A top view of a trilateral, quadrilateral, or pentagonal ring multiplier system as shown in fig. 8a, 8b, or 8 c. The adjacent polygonal dynodes of the same stage are connected with each other, so that the annular dynodes formed by surrounding the annular dynodes eliminate dead space, the carrying capacity of each stage of dynode pair electrons is further increased, and the linear current and pulse width response range of the photomultiplier are further improved.

Further, the photomultiplier can be designed into a ring dynode, as shown in fig. 9, compared with a polygonal dynode, the processing technology of the ring dynode is simpler, the connection effect is better, and more excellent electron multiplication performance can be realized, so that the linear current and the pulse width response range of the photomultiplier can be further improved.

In accordance with some embodiments of the present application, to achieve better inner and outer ring matching, the second photomultiplier subsystem 3033 may also be composed of conical dynodes, cylindrical dynodes, and annular dynodes, such as the first stage dynode conical dynode, with the latter dynodes being repeatedly alternated by annular dynodes and cylindrical dynodes.

Wherein, the conical dynode can be a cone or a pyramid, the generatrix of the conical dynode can be a straight line or a curve, and the conical dynode can also be a truncated cone.

The cylindrical dynode may be cylindrical or prismatic, and the top and/or bottom of the cylindrical dynode may be straight or curved, such as the top and/or bottom of the cylindrical dynode may be concave toward the center or convex outward, in a bell mouth shape. The bottom of the cylindrical dynode may be closed.

FIG. 11 shows a linear current comparison schematic of a photomultiplier tube having a different multiplication system, as shown in FIG. 11, with a linear deviation percentage of 5%, the linear current value of the conventional multiplication system is about 200mA, the linear current value of the trilateral annular multiplication system using the embodiment of the present application is about 280mA, the linear current value of the quadrilateral annular multiplication system using the embodiment of the present application is about 410mA, the linear current value of the pentagonal annular multiplication system using the embodiment of the present application is about 490mA, and the linear current value of the annular multiplication system using the embodiment of the present application is about 1000mA. The photomultiplier provided by the embodiment of the application greatly improves the linear current of the photomultiplier from the traditional level below 200mA to the level of ampere level, improves the pulse width response range of the photomultiplier, and can respond well to signals with pulse widths of 500 ns-microsecond level.

The embodiment of the application also provides a manufacturing method of the photomultiplier provided by the embodiment.

Fig. 10 shows a flow chart of a method of manufacturing a photomultiplier according to an exemplary embodiment of the present application, which includes a photocathode 301 and a photomultiplier system 303 according to an embodiment of the present application. Wherein the photocathode 301 is configured to receive photons and emit photoelectrons based on the received photons.

As shown in fig. 10, in step S1001, the photomultiplier system is disposed downstream of the photocathode 301 in such a manner as to surround the central axis of the photomultiplier tube, so that the photomultiplier system receives photoelectrons emitted from the photocathode 301 and multiplies the photoelectrons.

In an embodiment of the application, in step S1001, the photomultiplier system includes an electron-sharing structure disposed about a central axis of the photomultiplier tube.

In a specific embodiment, the photomultiplier system includes a plurality of first photomultiplier subsystems that together form an electron-sharing structure. The plurality of first photomultiplier tubes are connected in parallel with each other and are arranged around the central axis of the photomultiplier tube such that photoelectrons emitted from the photocathode 301 are incident on the plurality of first photomultiplier tubes, respectively.

In some embodiments, each of the first photomultiplier subsystems includes a plurality of tile-shaped dynodes, and the number of dynodes included in each of the first photomultiplier subsystems is the same.

In a specific embodiment, the dynodes of the same stage of each two adjacent photomultiplier subsystems in the first plurality of photomultiplier subsystems are connected to each other such that the same potential is applied between the dynodes of the same stage of the plurality of photomultiplier subsystems.

In other embodiments of the application, the photomultiplier system includes a second photomultiplier subsystem disposed downstream of the photocathode in a manner surrounding a central axis of the photomultiplier tube.

In a specific embodiment, the second photomultiplier subsystem is annular and the second photomultiplier subsystem includes a multi-stage annular dynode. The annular dynode includes an annular dynode, a columnar dynode, and/or a conical dynode, and the second photomultiplier subsystem is integrally formed as an electron-sharing structure.

The photomultiplier tube fabricated in FIG. 10 is used to respond to 500 ns-10 μs pulse width light signals in accordance with an embodiment of the present application.

In the present application, electron apportionment structure 3031 may include a plurality of electron apportionment regions, and photomultiplier system 303 may apportion and post-multiply photoelectrons through the plurality of electron apportionment regions of electron apportionment structure 3031. The plurality of electron apportioned regions of electron apportioned structure 3031 may be a continuous structure or may be separate structures. For example, as shown in fig. 5a, 5b and 5c, a trilateral multiplication system, a quadrilateral multiplication system and a pentagonal multiplication system, each of which can be used as an electron-sharing area to share photoelectrons in the whole space. Whereas the trilateral, quadrilateral, pentagonal multiplication systems shown in fig. 5a, 5b and 5c comprise three, four, five discrete structures, respectively. For another example, a circular ring-shaped multiplication system as shown in fig. 9, the entire ring of which can be regarded as a collection of a plurality of electron-sharing areas, that is, the electron-sharing areas of which are of a continuous structure.

As described above, the electron splitting structure in the present application is a structure that can split and then multiply incident photoelectrons by changing the number and/or shape of multiplication systems.

For example, as shown in fig. 5a to 5c, the electron splitting structure 3032 includes a plurality of first photomultiplier subsystems 3032, and the plurality of first photomultiplier subsystems 3032 respectively correspond to one splitting area of the photocathode 301, so that photoelectrons emitted by the photocathode 301 respectively enter the plurality of first photomultiplier subsystems 3032, and thus photoelectrons generated by the photocathode 301 are split and then multiplied, the electron collection number of each photomultiplier subsystem is reduced, and thus the generation probability of electron cloud is reduced under the condition that no action (such as an external electric field, a magnetic field, etc.) is applied to the movement track of the photoelectrons, and the pulse width response range of the photomultiplier and the linear current of the photomultiplier are improved.

For another example, the electron splitting structure 3033 shown in 8 a-8 c, after overcoming the dead space shown in fig. 5 a-5 c, multiplies the photoelectrons incident into the space, further increases the carrying capacity of each stage of multiplication pair electrons, and further improves the linear current and the pulse width response range of the photomultiplier.

It should be noted that, the method for manufacturing a photomultiplier provided by the embodiment of the present application can implement each process implemented by the embodiment of the photomultiplier, and can achieve the same technical effect, so that repetition is avoided, and details of the method for manufacturing a photomultiplier are not described in the embodiment of the method.

According to an embodiment of the application, a detector is proposed, comprising a photomultiplier as described above.

It should be noted that, the detector provided in the embodiment of the present application can implement each process implemented by the photomultiplier embodiment, and can achieve the same technical effect, so that repetition is avoided, and details of the above detector embodiment are not described.

The foregoing has outlined rather broadly the more detailed description of embodiments of the application in order that the detailed description of the principles and embodiments of the application may be implemented in conjunction with the detailed description of embodiments of the application that follows. Meanwhile, based on the idea of the present application, those skilled in the art can make changes or modifications on the specific embodiments and application scope of the present application, which belong to the protection scope of the present application. In view of the foregoing, this description should not be construed as limiting the application.

Claims (12)

1. A photomultiplier tube, comprising:

a photocathode for receiving photons and emitting photoelectrons based on the received photons;

the photomultiplier is positioned at the downstream of the photocathode and comprises an electron sharing structure, and is used for receiving the photoelectrons and carrying out sharing and multiplication on the photoelectrons through the electron sharing structure; and

an anode for collecting photoelectrons multiplied via the photomultiplier system and outputting an anode current based on the collected photoelectrons.

2. The photomultiplier tube of claim 1, wherein the electron-sharing structure is disposed about a target axis;

the target axis coincides with or is parallel to the central axis of the photomultiplier tube.

3. The photomultiplier tube of claim 1 or 2, wherein the photomultiplier system comprises a plurality of first photomultiplier subsystems disposed in parallel with each other and together comprising an electron-sharing structure.

4. The photomultiplier tube of claim 1 or 2, wherein the photomultiplier system comprises a second photomultiplier subsystem, the second photomultiplier subsystem being annular in shape, the second photomultiplier subsystem being integral as an electron-sharing structure.

5. The photomultiplier tube of claim 3, wherein each of the first photomultiplier subsystems comprises a multi-stage tiled dynode.

6. The photomultiplier tube of claim 5, wherein a plurality of tile-shaped dynodes of the same stage are arranged in parallel with each other.

7. The photomultiplier tube of claim 4, wherein the second photomultiplier subsystem comprises a multi-stage ring dynode.

8. The photomultiplier tube of claim 7, wherein the ring dynode comprises a ring dynode, a cylindrical dynode, a conical dynode, and/or a ring dynode surrounded by a polygonal dynode.

9. The photomultiplier tube of claim 7, wherein when the ring dynode includes a ring dynode surrounded by a plurality of polygon dynodes, each two adjacent polygon dynodes of the same stage are connected to each other.

10. The photomultiplier tube of claim 1, wherein the photomultiplier tube is configured to respond to an optical signal having a pulse width of 500 nanoseconds to 10 microseconds.

11. A method of manufacturing a photomultiplier tube according to any one of claims 1 to 10.

12. A detector comprising a photomultiplier tube according to any one of claims 1 to 10.