An image intensifier having a microchannel plate with double layer output electrodes

Abstract

This application relates to the technical field of low-light imaging and photoelectric detection, and discloses an image intensifier with a microchannel plate having dual-layer output electrodes. The intensifier includes a photocathode, a microchannel plate, and a fluorescent screen arranged sequentially along the directions of photon, photoelectron, and secondary electron propagation. The output end of the microchannel plate has a dual-layer output electrode structure, including a first output electrode layer, a high secondary electron multiplication layer, and a second output electrode layer stacked sequentially from the inside to the outside of the channel. This structure collimates and focuses the output electrons, thereby improving spatial resolution. The high secondary electron multiplication layer of the microchannel plate is an insulating material with a high secondary electron emission coefficient, which can compensate for the gain loss caused by the immersion of the first and second output electrode layers into the channel, improving the spatial resolution of the image intensifier while effectively maintaining its gain performance.

Description

Technical Field

[0001] This application relates to the field of low-light imaging and photoelectric detection technology, and discloses an image intensifier with a microchannel plate having a double-layer output electrode. Background Technology

[0002] An image intensifier is a vacuum optoelectronic device that converts weak light signals into enhanced visible light images. It is a type of low-light detector and uses a photocathode, microchannel plate, and fluorescent screen to achieve photoelectric conversion, electron multiplication, and fluorescence excitation to enhance images. It has important applications in low-light night vision, medical imaging, and scientific exploration.

[0003] Traditional methods for improving the spatial resolution of microchannel plates have many shortcomings. Reducing the aperture of the multiplication channel is a common method to improve spatial resolution, but microchannel plates have an optimal aspect ratio limit. Reducing the aperture inevitably requires reducing the thickness, which will reduce the mechanical strength of the microchannel plate and place higher demands on operation and application scenarios. Increasing the immersion depth of the output electrode is an effective method to improve the spatial resolution of microchannel plates, but since microchannel plates use nickel-chromium alloy as the electrode material, the secondary electron emission coefficient does not exceed 1. Increasing its immersion depth will increase the proportion of low emission efficiency regions in the channel, suppress secondary electron multiplication, and lead to a significant decrease in gain. It is difficult to maintain high gain performance while improving spatial resolution, which restricts the application of image intensifiers in high-quality imaging scenarios. Summary of the Invention

[0004] The purpose of this section is to outline some aspects of the embodiments of this application and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents, and such simplifications or omissions should not be construed as limiting the scope of this application.

[0005] To address the aforementioned technical problems, this application provides an image intensifier with a dual-layer output electrode microchannel plate, comprising: A photocathode, a microchannel plate, and a fluorescent screen are arranged sequentially along the directions of photon, photoelectron, and secondary electron propagation. The photocathode is used to receive incident light and generate an external photoelectric effect to complete photoelectric conversion; The microchannel plate includes a lead silicate glass substrate, multiple multiplication channels formed in the lead silicate glass substrate, a single-layer input electrode of the microchannel plate disposed near the photocathode, and a double-layer output electrode of the microchannel plate disposed near the fluorescent screen. The microchannel plate dual-layer output electrode includes a microchannel plate first output electrode layer, a microchannel plate high secondary electron multiplication layer and a microchannel plate second output electrode layer, which are stacked sequentially from the inside of the channel to the outside. The first output electrode layer and the second output electrode layer of the microchannel plate are made of conductive materials, and the high secondary electron multiplication layer of the microchannel plate is made of insulating material with a high secondary electron emission coefficient. The fluorescent screen is used to receive electrons multiplied by the microchannel plate and convert them into a visible light image; When different voltages are applied, the first and second output electrode layers of the microchannel plate form an electric lens effect, which collimates and focuses the electron beam output from the microchannel plate. At the same time, the high secondary electron emission characteristics of the high secondary electron multiplication layer of the microchannel plate compensate for the gain loss caused by the immersion of the first and second output electrode layers of the microchannel plate into the channel.

[0006] As a preferred embodiment of the image intensifier with a dual-layer output electrode microchannel plate according to this application, wherein: The single-layer input electrode of the microchannel plate, the first output electrode layer of the microchannel plate, and the second output electrode layer of the microchannel plate are all made of the same metallic conductive material.

[0007] As a preferred embodiment of the image intensifier with a dual-layer output electrode microchannel plate according to this application, wherein: The high secondary electron multiplication layer of the microchannel plate is composed of an insulating material with a secondary electron emission coefficient significantly higher than that of the lead silicate glass substrate.

[0008] As a preferred embodiment of the image intensifier with a dual-layer output electrode microchannel plate according to this application, wherein: The image intensifier contains multiple microchannel plates.

[0009] As a preferred embodiment of the image intensifier with a dual-layer output electrode microchannel plate according to this application, wherein: The multiple microchannel plates are arranged at non-parallel spatial angles.

[0010] As a preferred embodiment of the image intensifier with a dual-layer output electrode microchannel plate according to this application, wherein: In operation, the operating voltage applied to the photocathode, the single-layer input electrode of the microchannel plate, the first output electrode layer of the microchannel plate, the second output electrode layer of the microchannel plate, and the fluorescent screen increases progressively.

[0011] As a preferred embodiment of the image intensifier with a dual-layer output electrode microchannel plate according to this application, wherein: The first output electrode layer of the microchannel plate has the same thickness as the second output electrode layer of the microchannel plate.

[0012] As a preferred embodiment of the image intensifier with a dual-layer output electrode microchannel plate according to this application, wherein: The first output electrode layer, the high secondary electron multiplication layer, and the second output electrode layer of the microchannel plate are stacked in sequence with equal thickness along the radial direction of the multiplication channel towards the central axis.

[0013] As a preferred embodiment of the image intensifier with a dual-layer output electrode microchannel plate according to this application, wherein: The lengths of the first output electrode layer, the high secondary electron multiplication layer, and the second output electrode layer of the microchannel plate decrease sequentially along the axial direction of the multiplication channel towards the single-layer input electrode of the microchannel plate.

[0014] As a preferred embodiment of the image intensifier with a dual-layer output electrode microchannel plate according to this application, wherein: The shapes of the photocathode and the fluorescent screen match the shape of the microchannel plate, and the projected dimensions of the three in the direction perpendicular to the photoelectron propagation direction increase sequentially.

[0015] To optimize the above technical solution, the construction of the microchannel plate double-layer output electrode can also be achieved through the following process: S1: Evaporation deposition to form the first output electrode layer of the microchannel plate; S2: Evaporation deposition of an insulating material with high secondary electron emission capability to form a high secondary electron multiplication layer of the microchannel plate; S3: Evaporation deposition to form the second output electrode layer of the microchannel plate. During the above evaporation process, the immersion depth of the three functional materials along the channel axis of the microchannel plate decreases sequentially.

[0016] Furthermore, the immersion depth of each layer of material can be controlled by adjusting the angle between the evaporation source and the output end face of the microchannel plate. When the angle increases, the evaporation depth becomes shallower, and when the angle decreases, the evaporation depth becomes deeper.

[0017] The beneficial effects of this application are as follows: This application employs a microchannel plate dual-layer output electrode structure and applies an appropriate voltage difference between them to form an effective electric lens effect in the electrode area. This enables collimation and focusing of the electron beam output from the channel, suppresses the lateral diffusion of electrons during transmission, reduces the diameter of the light spot formed on the fluorescent screen, and directly improves the spatial resolution and imaging clarity of the image intensifier.

[0018] This application incorporates a high secondary electron multiplication layer made of a material with a high secondary electron emission coefficient between the two output electrodes of a microchannel plate. This layer generates abundant secondary electrons in its region, compensating for the decrease in secondary electron yield caused by the immersion of the first and second output electrode layers of the microchannel plate into the channel. This weakens the suppression effect of the output electrodes on the electron multiplication process, enabling the device to maintain a high gain level while achieving high resolution. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained through these drawings without creative effort. Wherein: Figure 1 A schematic diagram of an image intensifier with a dual-layer output electrode microchannel plate provided for this application; Figure 2 A schematic diagram of the fabrication process of the microchannel plate output end double electrode and the high secondary electron multiplication layer of the microchannel plate for an image intensifier with a double-layer output electrode microchannel plate provided in this application; Figure 3 A schematic diagram of a process for controlling the film immersion depth by adjusting the included angle of the evaporation source in an image intensifier with a dual-layer output electrode microchannel plate, provided for this application; Figure 4 The following is a simulation comparison of the electron speckle distribution of the fluorescent screen with the traditional structure and the structure of this invention, wherein: Figure 4 (a) shows the speckle distribution of a traditional single-layer output electrode structure; Figure 4 (b) shows the speckle distribution of the dual-layer output electrode structure of the present invention; Figure 4 (c) Statistical distribution of speckle patterns along the X and Y directions in traditional structures; Figure 4 (d) is a statistical representation of the positional distribution of the speckle pattern in the structure of the present invention along the X and Y directions; In the figure: 1. Photocathode; 2. Single-layer input electrode of microchannel plate; 3. Microchannel plate multiplication channel; 4. Lead silicate glass of microchannel plate; 5. First output electrode layer of microchannel plate; 6. Second output electrode layer of microchannel plate; 7. High secondary electron multiplication layer of microchannel plate; 8. Fluorescent screen. Detailed Implementation

[0020] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0021] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0022] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of this application. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single embodiment or an embodiment selectively excluded from other embodiments.

[0023] Example 1 An image intensifier with a dual-layer output electrode microchannel plate includes a photocathode, a microchannel plate, and a fluorescent screen arranged sequentially along the direction of photon, photoelectron, and secondary electron propagation.

[0024] The photocathode is used to receive incident light and generate an external photoelectric effect to complete photoelectric conversion; The microchannel plate includes a lead silicate glass substrate, a plurality of multiplication channels formed in the lead silicate glass substrate, a single-layer input electrode of the microchannel plate disposed on the side facing the photocathode, and a double-layer output electrode structure of the microchannel plate disposed on the side facing the fluorescent screen.

[0025] The microchannel plate dual-layer output electrode structure comprises layers stacked sequentially from the inside of the channel to the outside: The first output electrode layer of the microchannel plate is made of a conductive material. The high secondary electron multiplication layer of the microchannel plate is an insulating material with a high secondary electron emission coefficient; The second output electrode layer of the microchannel plate is made of conductive material.

[0026] The fluorescent screen is used to receive electrons multiplied by the microchannel plate and convert them into visible light images.

[0027] When different potentials are applied to the first and second output electrode layers of the microchannel plate, a longitudinal electric field can be formed between them. This electric field couples with the transverse electric field on the channel wall surface to form an electric lens effect, which collimates and focuses the electron beam output from the microchannel plate. At the same time, the high secondary electron emission characteristics of the high secondary electron multiplication layer of the microchannel plate can compensate for the gain loss caused by the immersion of the first and second output electrode layers of the microchannel plate into the channel.

[0028] The materials of the single-layer input electrode, the first output electrode layer, and the second output electrode layer of the microchannel plate are all nickel-chromium alloys.

[0029] The material of the high secondary electron multiplication layer of the microchannel plate is Al2O3 or MgO, and its secondary electron emission coefficient is significantly higher than that of the lead silicate glass substrate.

[0030] The image intensifier may include 1 to 3 microchannel plates, with two microchannel plates stacked in a V-shape and three microchannel plates stacked in a Z-shape.

[0031] The operating voltage applied to the photocathode, the single-layer input electrode of the microchannel plate, the first output electrode layer of the microchannel plate, the second output electrode layer of the microchannel plate, and the fluorescent screen increases progressively.

[0032] The first output electrode layer of the microchannel plate has the same thickness as the second output electrode layer of the microchannel plate.

[0033] The first output electrode layer, the high secondary electron multiplication layer, and the second output electrode layer of the microchannel plate are stacked in sequence with equal thickness along the radial direction of the multiplication channel towards the central axis.

[0034] The lengths of the first output electrode layer, the high secondary electron multiplication layer, and the second output electrode layer of the microchannel plate decrease sequentially along the axial direction of the multiplication channel towards the single-layer input electrode of the microchannel plate.

[0035] The projected dimensions of the photocathode, microchannel plate, and fluorescent screen increase slightly in sequence, perpendicular to the direction of photoelectron propagation.

[0036] Example 2 like Figure 1 As shown, an image intensifier with a dual-layer output electrode microchannel plate includes: It includes a photocathode 1, a microchannel plate, and a fluorescent screen 8 arranged sequentially along the direction of photon, photoelectron, and secondary electron propagation.

[0037] The photocathode 1 is located at the top of the image intensifier and is used to achieve photoelectric conversion. Its material can be infrared Ag-O-Cs, dual-base Cs-Sb, multi-base Na2KCsSb, or negative electron affinity GaAs, etc. The shape of the photocathode 1 can match the microchannel plate, for example, it can be circular or square, and its size is slightly smaller than the microchannel plate. The operating voltage of the photocathode 1 is the lowest in the entire device. In this embodiment, the photocathode 1 is circular with a diameter of 24 mm and an operating voltage of 0 V.

[0038] The microchannel plate is located directly below the photocathode 1 and is used to achieve electron multiplication. The structure includes a single-layer input electrode 2 of the microchannel plate, a multiplication channel 3, a lead silicate glass substrate 4, a first output electrode layer 5 of the microchannel plate, a second output electrode layer 6 of the microchannel plate, and a high secondary electron multiplication layer 7 of the microchannel plate located between the two output electrode layers.

[0039] The overall shape of the microchannel plate can be circular or square, with dimensions slightly smaller than the fluorescent screen 8. Its diameter is adjustable from 10mm to 100mm, and its thickness is adjustable from 0.3mm to 1.2mm. In this embodiment, a circular microchannel plate with a diameter of 25mm and a thickness of 0.32mm is used.

[0040] The single-layer input electrode 2 of the microchannel plate faces the photocathode 1 and is made of nickel-chromium alloy. Its immersion depth along the channel axis is 0.3 to 3 times the channel aperture, and the distance between it and the photocathode 1 is adjustable from 100 μm to 1000 μm. The operating voltage is approximately 50V to 1000V higher than that of the photocathode 1. In this embodiment, the immersion depth of the single-layer input electrode 2 of the microchannel plate is 0.5 times the channel aperture, the distance between it and the photocathode 1 is 200 μm, and the operating voltage is 100V.

[0041] The microchannel plate contains hundreds of thousands of multiplication channels 3, with channel diameters adjustable from 5μm to 20μm and channel tilt angles adjustable from 5° to 15°. In this embodiment, the channel diameter is 6μm and the tilt angle is 7°.

[0042] The lead silicate glass substrate 4 exhibits secondary electron emission characteristics, with its secondary electron emission coefficient peak value typically between 2 and 5. In this embodiment, when the incident electron energy is 320 eV, the secondary electron emission coefficient peak value is 3.7.

[0043] Both the first output electrode layer 5 and the second output electrode layer 6 of the microchannel plate are made of nickel-chromium alloy. The first output electrode layer 5, the high electron multiplication layer 7, and the second output electrode layer 6 are stacked sequentially along the radial direction of the multiplication channel, pointing towards the central axis, with equal thicknesses. The second output electrode layer 6 is located near the fluorescent screen 8 and is immersed in the channel, while the first output electrode layer 5 is located near the single-layer input electrode 2 and is also immersed in the channel. The lengths of the first output electrode layer 5, the high electron multiplication layer 7, and the second output electrode layer 6 decrease sequentially along the axial direction of the multiplication channel towards the single-layer input electrode. Externally, the width of both electrode layers is 0.3 to 3 times the channel aperture. The operating voltage of the second output electrode layer 6 of the microchannel plate can be 600V to 1200V higher than that of the single-layer input electrode 2 of the microchannel plate, while the operating voltage of the first output electrode layer 5 of the microchannel plate can be approximately 10V to 200V lower than that of the second output electrode layer 6. In this embodiment, the immersion depth of both electrode layers is 0.5 times the channel aperture, the operating voltage of the second output electrode layer 6 of the microchannel plate is 1100V, and the operating voltage of the first output electrode layer 5 of the microchannel plate is 1020V.

[0044] The high secondary electron multiplication layer 7 of the microchannel plate, located between the first output electrode layer 5 and the second output electrode layer 6, is an insulating material with a high secondary electron emission coefficient, which is higher than that of the lead silicate glass substrate 4. The width of this layer can be 0.3 to 3 times the channel aperture. In this embodiment, Al2O3 material is used, which has a peak secondary electron emission coefficient of 6.4 at an incident electron energy of 650 eV, and a layer width of 7 μm.

[0045] The first output electrode layer 5, the high secondary electron multiplication layer 7, and the second output electrode layer 6 of the microchannel plate are sequentially prepared by a vapor deposition process, as follows: Figure 2 As shown, the specific steps include: S1, vapor deposition of nickel-chromium alloy to form the first output electrode layer 5 of the microchannel plate; S2, vapor deposition of insulating materials with high secondary electron emission coefficients, such as Al2O3, to form the high secondary electron multiplication layer 7 of the microchannel plate; S3, vapor deposition of nickel-chromium alloy to form the second output electrode layer 6 of the microchannel plate. During the vapor deposition process, the longitudinal immersion depth of each material layer along the channel wall can be controlled by adjusting the angle between the evaporation source and the output end face of the microchannel plate. Figure 3 As shown: the larger the included angle, the shallower the vapor deposition depth; the smaller the included angle, the deeper the vapor deposition depth, thus achieving a gradient structure in which the immersion depth of the three layers of materials decreases sequentially.

[0046] The fluorescent screen 8, located directly below the microchannel plate, is used for electro-optical conversion and can be made of fluorescent materials such as P20-AF, P20, P43, or P46. The shape of the fluorescent screen 8 matches the microchannel plate, for example, it can be circular or square, and its size is slightly larger than the microchannel plate. The distance between the fluorescent screen 8 and the second output electrode layer 6 of the microchannel plate can be adjusted from 100 μm to 1000 μm, and its operating voltage is the highest in the entire image intensifier, typically 50V to 1000V higher than the voltage of the second output electrode layer 6 of the microchannel plate. In this embodiment, the fluorescent screen 8 is circular, the distance between it and the second output electrode layer 6 of the microchannel plate is 200 μm, and the operating voltage is set to 1200V.

[0047] In operation, the operating voltage applied to the photocathode 1, the single-layer input electrode 2 of the microchannel plate, the first output electrode layer 5 of the microchannel plate, the second output electrode layer 6 of the microchannel plate, and the fluorescent screen 8 increases progressively.

[0048] When different voltages are applied, the first and second output electrode layers of the microchannel plate can form an effective electric lens effect in the electrode region, enabling collimation and focusing of the output electron beam, suppressing lateral diffusion of electrons during transmission, reducing the diameter of the light spot formed on the fluorescent screen, and directly improving the spatial resolution and imaging clarity of the image intensifier. The high secondary electron multiplication layer can generate abundant secondary electrons, thereby compensating for the decrease in secondary electron yield caused by the immersion of the first and second output electrode layers of the microchannel plate into the channel, weakening the suppression effect of the output electrodes on the electron multiplication process, so that the device can maintain a high gain level while achieving high resolution.

[0049] To verify the technical effect of the present invention, the spatial resolution and gain of the dual-layer output electrode image intensifier of this embodiment were simulated and evaluated using the finite integration method, Monte Carlo method and Furman secondary electron emission model.

[0050] Figure 4 (a) and Figure 4 (b) The electron speckle distribution on the fluorescent screen under the traditional single-layer output electrode structure and the double-layer electrode structure of the present invention are shown respectively. The positional distribution of the speckle along the X and Y directions is statistically analyzed, and the results are as follows: Figure 4 (c) Figure 4 (d) The full width at half maximum (FWHM) of the speckle pattern in the conventional structure is 47.159 μm in the X direction and 51.382 μm in the Y direction; while the FWHM of the speckle pattern in the structure of this invention is significantly reduced to 26.762 μm in the X direction and 39.984 μm in the Y direction. This indicates that the double-layer electrode structure of this invention effectively focuses the output electrons through the electric lens effect, significantly improving the spatial resolution of the image intensifier.

[0051] Regarding gain, the structure of this invention achieves a gain of 7729 at the aforementioned high resolution (FWHM-X = 26.762 μm). To achieve a similar resolution level of FWHM-X = 27.752 μm, the conventional structure requires a significant increase in the immersion depth of the output electrode to 12 μm, but its gain drops to 4813. This comparative result demonstrates that the present invention successfully compensates for the gain loss by introducing a high-emission-coefficient microchannel plate with high secondary electron multiplication layer between the two electrode layers, achieving simultaneous optimization of the image intensifier gain performance.

[0052] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only two embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible without substantially departing from the novel teachings and advantages of the subject matter described in this application. These modifications may include variations in the size, dimensions, structure, shape, and proportions of various elements, as well as parameter values, installation arrangements, use of materials, color, orientation, etc. For example, an element shown as integrally formed may be composed of multiple parts or elements, the position of elements may be inverted or otherwise altered, and the nature or number or position of discrete elements may be changed or altered. Therefore, all such modifications are intended to be included within the scope of this application. The order or sequence of any process or method steps may be changed or rearranged by alternative embodiments. Any "apparatus plus function" clause is intended to cover the structure performing the function described herein, and not only structurally equivalent but also equivalent in structure. Other substitutions, modifications, alterations, and omissions may be made in the design, operation, and arrangement of the exemplary embodiments without departing from the scope of this application. Therefore, this application is not limited to a particular embodiment, but extends to various modifications that still fall within the scope of the appended claims.

[0053] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of actual embodiments (i.e., those features that are not relevant to the best mode of performing this application as currently considered, or those features that are not relevant to implementing this application) may be omitted.

[0054] It should be understood that numerous specific implementation decisions can be made during the development of any practical implementation, such as in any engineering or design project. Such development efforts may be complex and time-consuming, but for those of ordinary skill in the art who benefit from this disclosure, the development effort will be a routine task in design, manufacturing, and production without requiring extensive experimentation.

[0055] It should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application without departing from the spirit and scope of the technical solutions of this application, and all such modifications and substitutions should be covered within the scope of the claims of this application.

Claims

1. An image intensifier having a dual-layer output electrode microchannel plate, characterized in that, include: A photocathode, a microchannel plate, and a fluorescent screen are arranged sequentially along the directions of photon, photoelectron, and secondary electron propagation. The photocathode is used to receive incident light and generate an external photoelectric effect to complete photoelectric conversion; The microchannel plate includes a lead silicate glass substrate, a single-layer input electrode of the microchannel plate with multiple multiplier channels formed in the lead silicate glass substrate and disposed near the photocathode, and a double-layer output electrode of the microchannel plate disposed near the fluorescent screen. The microchannel plate dual-layer output electrode includes a microchannel plate first output electrode layer, a microchannel plate high secondary electron multiplication layer and a microchannel plate second output electrode layer, which are stacked sequentially from the inside of the channel to the outside. The first output electrode layer and the second output electrode layer of the microchannel plate are made of conductive materials, and the high secondary electron multiplication layer of the microchannel plate is made of insulating material with a high secondary electron emission coefficient. The fluorescent screen is used to receive electrons multiplied by the microchannel plate and convert them into a visible light image; When different voltages are applied, the first and second output electrode layers of the microchannel plate form an electric lens effect, which collimates and focuses the electron beam output from the microchannel plate. At the same time, the high secondary electron emission characteristics of the high secondary electron multiplication layer of the microchannel plate compensate for the gain loss caused by the immersion of the first and second output electrode layers of the microchannel plate into the channel.

2. The image intensifier with a dual-layer output electrode microchannel plate as described in claim 1, characterized in that: The single-layer input electrode of the microchannel plate, the first output electrode layer of the microchannel plate, and the second output electrode layer of the microchannel plate are all made of the same metallic conductive material.

3. The image intensifier with a dual-layer output electrode microchannel plate as described in claim 1, characterized in that: The high secondary electron multiplication layer of the microchannel plate is composed of an insulating material with a secondary electron emission coefficient significantly higher than that of the lead silicate glass substrate.

4. The image intensifier with a dual-layer output electrode microchannel plate as described in claim 1, characterized in that: The image intensifier contains multiple microchannel plates.

5. An image intensifier with a dual-layer output electrode microchannel plate as described in claim 4, characterized in that: The multiple microchannel plates are arranged at non-parallel spatial angles.

6. The image intensifier with a dual-layer output electrode microchannel plate as described in claim 1, characterized in that: In operation, the operating voltage applied to the photocathode, the single-layer input electrode of the microchannel plate, the first output electrode layer of the microchannel plate, the second output electrode layer of the microchannel plate, and the fluorescent screen increases progressively.

7. An image intensifier with a dual-layer output electrode microchannel plate as described in claim 1, characterized in that: The first output electrode layer of the microchannel plate has the same thickness as the second output electrode layer of the microchannel plate.

8. An image intensifier with a dual-layer output electrode microchannel plate as described in claim 1, characterized in that: The first output electrode layer, the high secondary electron multiplication layer, and the second output electrode layer of the microchannel plate are stacked in sequence with equal thickness along the radial direction of the multiplication channel towards the central axis.

9. An image intensifier with a dual-layer output electrode microchannel plate as described in claim 8, characterized in that: The lengths of the first output electrode layer, the high secondary electron multiplication layer, and the second output electrode layer of the microchannel plate decrease sequentially along the axial direction of the multiplication channel towards the single-layer input electrode of the microchannel plate.

10. An image intensifier with a dual-layer output electrode microchannel plate as described in claim 1, characterized in that: The shapes of the photocathode and the fluorescent screen match the shape of the microchannel plate, and the projected dimensions of the three in the direction perpendicular to the photoelectron propagation direction increase sequentially.

Images