Slicer gas injection device and vacuum microcell charge neutralization system

Abstract

The invention belongs to the technical field of electron microscope accessories, and provides a slicer gas injection device and a vacuum microcell charge neutralization system, and the slicer gas injection device comprises a gas injection unit, a gas switch trigger, a gas quality controller and a software control unit. The software control unit gives different signals to the gas quality controller so as to control gas injection; the gas quality controller is used for adjusting the gas flow and opening and closing a gas path; the gas switch trigger is used for triggering a gas path switch instruction when a slicing action occurs, so that the ventilation efficiency is improved; the gas injection movement unit controls movement of the gas injection needle head and adjusts the ventilation position in real time. According to the invention, the charge effect encountered by the scanning electron microscope during three-dimensional continuous slicing of the biological sample can be effectively solved, the quality and stability of image acquisition are maintained, negative effects on the service life or / and the structure of the scanning electron microscope are avoided, and the problems of difficult imaging and poor imaging during three-dimensional continuous slicing of the biological sample are solved.

Description

Technical Field

[0001] The present application belongs to the technical field of electron microscope accessories, and specifically relates to a microtome gas injection device and a vacuum micro-area charge neutralization system. Background Art

[0002] In microstructural studies of biological samples such as plants, scanning electron microscopy, with its high-resolution imaging capabilities, has become a key technique for observing surface morphology, cell form, and tissue characteristics. This technique not only provides intuitive morphological evidence for plant taxonomy, physiology, and pathology, but also assists in analyzing the physical and chemical properties of material surfaces during plant material development.

[0003] When a scanning electron microscope is used for imaging, a particle beam formed by electrons is used to irradiate the sample surface, leaving negatively charged electrons on the sample. However, plant samples are mostly non-conductors, and their surfaces easily accumulate charges when bombarded by the electron beam, resulting in a charging effect, which causes image distortion, blurring, or even the inability to form an image. This problem has become a core technical bottleneck restricting the precise application of scanning electron microscopes in plant sample research.

[0004] At present, conventional technologies mainly adopt two solutions to the charging effect in scanning electron microscope imaging: one is the low vacuum imaging mode, which reduces the local vacuum degree to suppress charge accumulation by introducing nitrogen and other gases into the electron microscope chamber on a large scale. However, this method requires destroying the overall high vacuum environment of the electron microscope, which violates the working requirement of the scanning electron microscope that relies on high vacuum to maintain the stability of the electron beam. In addition, the interaction between gas molecules and the electron beam will interfere with the incident electron path and signal electron collection, resulting in a significant decrease in image resolution and signal-to-noise ratio. The second is to spray a conductive film on the sample surface. Although it can alleviate the charging effect in the short term, the spraying process can easily mask the nanoscale fine structure of the sample surface, introduce artifacts and reduce the authenticity of the structural representation. In particular, in the workflow of three-dimensional continuous section imaging, the sample surface is continuously cut, making the originally sprayed conductive layer unable to continue, thereby greatly reducing the conductive effect of the spraying and failing to solve the charging effect. Summary of the Invention

[0005] In order to solve the problem of difficulty and poor imaging in existing scanning electron microscopes when imaging three-dimensional continuous slices of biological samples, the present application provides a microtome gas injection device and a vacuum micro-area charge neutralization system.

[0006] In one embodiment, a microtome gas injection device is provided, which is mounted on a microtome built into a scanning electron microscope, and includes a gas injection unit and a gas switch trigger;

[0007] The gas injection unit includes a holder, a movable holder, a telescopic mechanism, and a needle tube; the holder is fixedly connected to the microtome, and the movable holder is fixedly connected to the holder via the telescopic mechanism; the needle tube is clamped on the movable holder, and one end of the needle tube is connected to the air inlet pipe, and the other end of the needle tube extends to the sample platform of the microtome;

[0008] The gas switch trigger includes a contact plate, the two ends of which are a connecting end and a triggering end, the connecting end is fixedly connected to the movable base; the triggering end faces the blade holder of the slicer and is used to sense the slicing action of the slicer;

[0009] The slicer performs a slicing action, driving the sample platform and the knife holder to move along the first horizontal direction, causing the knife holder to contact the trigger end, thereby activating the telescopic mechanism to drive the movable base to move along the first horizontal direction. The movable base carries the needle tube and moves in coordination with the sample platform. At the same time, the air inlet pipe supplies air, and the needle tube injects gas into the sample on the sample platform.

[0010] In one embodiment, the trigger end is provided with a contact element;

[0011] When the microtome performs a slicing action, the knife holder moves along the first horizontal direction and contacts the contact element, activating the gas injection unit, and the telescopic mechanism drives the movable seat to move away from the sample platform and opens the gas path of the air inlet pipe;

[0012] After the single slicing action of the microtome is completed, the knife holder and sample platform retract and reset, the contact element separates from the knife holder, the telescopic mechanism drives the moving seat to move toward the sample platform and reset, and the air path of the air inlet pipe is closed;

[0013] The contact element can also adjust its relative position along the first horizontal direction, thereby adjusting the response speed of the gas switch trigger to the slicing action.

[0014] In one embodiment, an insulating plate is provided on the end surface of the tool holder adjacent to the trigger end, and a contact piece is provided on the side of the insulating plate facing away from the tool holder;

[0015] When the slicer performs slicing action and drives the knife holder to move, the contact piece contacts the contact element.

[0016] Furthermore, the gas switch trigger further includes a collision plate;

[0017] The collision plate and the contact plate are symmetrically arranged along the second horizontal direction, and the collision plate and the contact plate are respectively detachably fixedly connected to the movable seat;

[0018] When the slicer performs a slicing action, when the knife holder moves along the first horizontal direction, the knife holder contacts the collision plate and the contact element at the same time, or the knife holder contacts the contact element first.

[0019] In one embodiment, the gas injection unit further comprises a channel box;

[0020] The channel box is fixedly connected to the movable seat; the channel box is provided with an adjustment hole along a first horizontal direction, and the diameter of the adjustment hole is larger than the outer diameter of the needle tube; a part of the structural section of the needle tube passes through the adjustment hole;

[0021] The channel box is also provided with a locking element; the locking element extends inwardly from the outer end surface of the channel box to the adjustment hole, and the locking element can movably fix the needle tube;

[0022] When the locking element locks and fixes the needle tube, the movable seat can drive the needle tube to move along the first horizontal direction under the drive of the telescopic mechanism;

[0023] When the locking element releases the fixation of the needle tube, the needle tube can move in the adjustment hole, thereby adjusting the relative position of the needle in the first horizontal direction and / or the second horizontal direction to adapt the position of the needle to the sample on the sample platform.

[0024] In one embodiment, the movable base includes a supporting section and connecting blocks configured at both ends of the supporting section;

[0025] A receiving groove is formed in the central area of the support section along a first horizontal direction, and a partial structural section of the needle tube is clamped in the receiving groove;

[0026] One end of each connecting block facing away from the tool holder is fixedly connected to the telescopic mechanism, and one end of each connecting block facing the tool holder is fixedly connected to the connecting end.

[0027] To achieve the above objectives, the present application also provides a vacuum micro-area charge neutralization system, including the slicer gas injection device of the aforementioned solution.

[0028] In one embodiment, the vacuum micro-area charge neutralization system further includes a software control unit and a gas quality controller;

[0029] The software control unit, gas quality controller, and microtome gas injection device are all installed on the microtome built into the scanning electron microscope;

[0030] The software control unit comprises a processor and an operation module externally mounted on the scanning electron microscope cavity; the gas mass controller comprises a flow valve, and the gas mass controller is mounted on the air inlet pipe;

[0031] The gas switch trigger, the gas injection unit and the gas quality controller are all electrically connected to the software control unit.

[0032] The software control unit is used to receive the electronic signal sent by the gas switch trigger and send electronic signals to the gas quality controller and the gas injection unit;

[0033] The staff can use the operation module to adjust the electronic signals sent by the software control unit, thereby controlling and adjusting the actions of the gas quality controller and the gas injection unit.

[0034] Furthermore, the gas quality controller is a functional component that realizes gas flow regulation and gas path opening and closing;

[0035] When the gas switch trigger senses the slicing action of the microtome, the gas switch trigger sends an action signal to the software control unit; after receiving the action signal, the software control unit sends signals to the gas mass controller and the gas injection unit respectively, activating the gas mass controller to open the gas path of the air inlet pipe, and at the same time, the gas injection unit moves to adjust the gas injection position of the needle;

[0036] When the tool holder loses contact with the gas switch trigger, the gas switch trigger sends a reset signal to the software control unit; after receiving the reset signal, the software control unit sends corresponding signals to the gas mass controller and the gas injection unit respectively. The gas mass controller closes the gas path of the air inlet pipe, and at the same time, the gas injection unit drives the needle tube to reset and move;

[0037] When adjusting the gas flow in the intake pipe, the staff uses the operation module to control the software control unit to send corresponding adjustment electronic signals to the gas quality controller, and the gas quality controller adjusts the opening of the valve components in the intake pipe accordingly.

[0038] Beneficial effects of this application:

[0039] The microtome gas injection device and vacuum micro-area charge neutralization system of the present application synchronously inject a trace amount of gas into the sample area by sensing the operating state of the microtome. Without destroying the overall high vacuum environment of the electron microscope, the charge neutralization of the local area is achieved, thus avoiding the damage to the performance of the electron microscope caused by the traditional low-vacuum imaging mode, ensuring the stability of the electron beam and the long-term imaging accuracy, and having high vacuum environment compatibility.

[0040] At the same time, the gas injection amount and the action area can be precisely controlled, and charge neutralization is performed only on the charged micro-areas, avoiding the global interference of gas molecules on the incident electrons and signal electrons, and ensuring the high resolution and signal-to-noise ratio of the image; and this application does not require the sample to be processed such as spraying, and directly retains the original structural details of the sample surface, solving the artifact problem caused by traditional spraying methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0042] Figure 1 is a schematic diagram of a gas injection device for a slicer in one embodiment of the present application;

[0043] Figure 2 is a top view of a gas injection device for a slicer according to an embodiment of the present application;

[0044] Figure 3 is a schematic diagram of a gas injection device for a slicer in one embodiment of the present application;

[0045] Figure 4 This is a partial exploded view of a gas injection device for a slicer in one embodiment of the present application;

[0046] Figure 5 This is a schematic diagram of the system modules of the vacuum micro-area charge neutralization system in one embodiment of the present application;

[0047] Reference numerals in the figures:

[0048] 1. Gas injection unit; 11. Card seat; 12. Moving seat; 13. Telescopic mechanism; 14. Needle tube; 15. Channel box;

[0049] 2. Gas switch trigger; 21. Contact plate; 211. Contact element; 22. Impact plate;

[0050] 3. Microtome; 31. Sample platform; 32. Knife holder; 321. Insulation plate; 322. Contact piece;

[0051] 4. Intake pipe;

[0052] Define X as the first horizontal direction; define Y as the second horizontal direction. DETAILED DESCRIPTION

[0053] The specific embodiments of the present application are further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application, but are not intended to limit the scope of the present application. Similarly, the following examples are only some embodiments of the present application and not all embodiments. All other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0054] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0055] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. Throughout the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0056] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0057] In this application, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0058] To address the issues mentioned in the background art regarding the difficulty and poor imaging of three-dimensional serial slices of biological samples using current scanning electron microscopes, the present application provides a microtome gas injection device and a vacuum micro-area charge neutralization system. Specific embodiments are as follows:

[0059] In one embodiment, see Figure 1 and Figure 2 A microtome gas injection device is installed on a microtome 3 built into a scanning electron microscope. The device includes a gas injection unit 1 and a gas switch trigger 2.

[0060] In this embodiment, the gas injection unit 1 includes a base 11, a movable base 12, a telescopic mechanism 13 and a needle tube 14; the base 11 is fixedly connected to the slicer 3, and the movable base 12 is fixedly connected to the base 11 through the telescopic mechanism 13; the needle tube 14 is clamped on the movable base 12, and one end of the needle tube 14 is connected to the air inlet pipe 4, and the other end of the needle tube 14 extends to the sample platform 31 of the slicer 3.

[0061] Among them, the telescopic mechanism 13 can be specifically an electric telescopic rod, a hydraulic cylinder, an electric cylinder, etc.; in particular, the telescopic mechanism 13 can also be provided with elastic components such as compression springs to assist in resetting and buffering; the needle part of the needle tube 14 can be processed into a flat head porous structure to make the gas injection more uniform.

[0062] In this embodiment, the gas switch trigger 2 includes a contact plate 21, the two ends of the contact plate 21 are a connecting end and a triggering end, the connecting end is fixedly connected to the movable seat 12; the triggering end faces the blade holder 32 of the slicer 3 and is used to sense the slicing action of the slicer 3.

[0063] In this embodiment, the slicer 3 performs a slicing action, driving the sample platform 31 and the knife holder 32 to move along the first horizontal direction X, so that the knife holder 32 contacts the trigger end, thereby activating the telescopic mechanism 13 to drive the movable base 12 to move along the first horizontal direction X. The movable base 12 carries the needle tube 14 to move in coordination with the sample platform 31. At the same time, the air inlet pipe 4 supplies air, and the needle tube 14 injects gas into the sample on the sample platform 31.

[0064] Therefore, the microtome gas injection device is a device that can inject trace amounts of gas into specific areas without destroying the existing vacuum environment. It not only eliminates the generation and persistence of the charging effect from the root cause of the charging effect, but also reduces the interference and hidden dangers caused by the conductivity of the sample during the use of the scanning electron microscope, and maintains the original state of the incident electron beam of the scanning electron microscope and the signal electrons of the sample itself, avoiding problems such as artifacts or false images caused by the elimination of the charging effect.

[0065] In one embodiment, see Figure 2 and Figure 3 Based on the above embodiment, the trigger end is provided with a contact element 211.

[0066] In this embodiment, when the microtome 3 performs a slicing action, the knife holder 32 moves along the first horizontal direction X and contacts the contact element 211, activating the gas injection unit 1. The telescopic mechanism 13 drives the movable seat 12 to move away from the sample platform 31 and opens the air path of the air inlet pipe 4, so that the needle tube 14 starts to supply air to the sample platform 31.

[0067] Accordingly, the single slicing action of the slicer 3 is completed, the knife holder 32 and the sample platform 31 retreat and reset, the contact element 211 separates from the knife holder 32, the telescopic mechanism 13 drives the movable seat 12 to move and reset in the direction of the sample platform 31, and closes the air path of the air inlet pipe 4, and the needle tube 14 stops supplying air to the sample platform 31.

[0068] In this embodiment, the contact element 211 can also adjust its relative position along the first horizontal direction X, thereby adjusting the response speed of the gas switch trigger 2 to the slicing action. For example, the contact element 211 can be a screw mounted on the contact plate 21, with at least one screw mounting hole defined at the trigger end, allowing the contact element 211 to flexibly adjust its contact position with the blade holder 32.

[0069] In one embodiment, see Figure 3 and Figure 4 An insulating plate 321 is provided on the end surface of the blade holder 32 adjacent to the trigger end, and a contact piece 322 is provided on the side of the insulating plate 321 facing away from the blade holder 32; when the slicer 3 performs a slicing action and drives the blade holder 32 to move, the contact piece 322 contacts the contact element 211.

[0070] In this embodiment, to facilitate independent control of the slicing, gas injection, and imaging steps, the scanning electron microscope's imaging control circuit, the microtome control circuit, and the gas injection device control circuit are three independent circuit systems, each of which cannot directly communicate with each other. However, because the blade holder 32 is a conductive metal structure, contact between the blade holder 32 and the contact element 211 could potentially cause electrical connection between the microtome control circuit and the gas injection device control circuit. Therefore, the provision of an insulating plate 321 on the end surface of the blade holder 32 ensures the mutual independence of the microtome control circuit and the gas injection device control circuit, facilitating independent control and adjustment of each component's functions while minimizing changes to the original operating environment and hardware environment of the device.

[0071] In one embodiment, see Figure 2 and Figure 3 Based on the aforementioned embodiment, the gas switch trigger 2 further includes a collision plate 22 .

[0072] In this embodiment, the collision plate 22 and the contact plate 21 are symmetrically arranged along the second horizontal direction Y, and the collision plate 22 and the contact plate 21 are each detachably fixedly connected to the movable base 12. The collision plate 22 serves as a balancing structure for the contact plate 21. Since the center of the movable base 12 needs to allow the needle tube 14 to pass through, the contact plate 21 needs to be arranged along both ends of the movable base 12. To ensure structural balance, stability, and aesthetics, the collision plate 22 is provided to cooperate with the contact plate 21.

[0073] When the slicer 3 performs a slicing operation and the blade holder 32 moves along the first horizontal direction X, the blade holder 32 may simultaneously contact the collision plate 22 and the contact element 211, or the blade holder 32 may first contact the contact element 211. In other words, the blade holder 32 may make single-point contact with the contact plate 21, or may make simultaneous contact with both the collision plate 22 and the contact plate 21. This prevents the blade holder 32 from contacting only the collision plate 22, which could cause inductive failure during the slicing operation and affect the normal gas injection process.

[0074] In particular, two contact plates 21 can be symmetrically provided along the second horizontal direction Y, that is, a new contact plate 21 is used to replace the collision plate 22, and the tool holder 32 is in contact with the gas switch trigger 2 in a double contact point manner.

[0075] In one embodiment, see Figures 2 to 4 Based on the aforementioned embodiment, the gas injection unit 1 further includes a channel box 15 .

[0076] In this embodiment, the channel box 15 is fixedly connected to the movable seat 12; the channel box 15 has an adjustment hole along the first horizontal direction X, and the diameter of the adjustment hole is larger than the outer diameter of the needle tube 14; a partial structural section of the needle tube 14 passes through the adjustment hole.

[0077] In this embodiment, the channel box 15 is further provided with a locking element; the locking element extends inward from the outer end surface of the channel box 15 into the adjustment hole, and the locking element can movably secure the needle tube 14. For example, the locking element can be an adjustment bolt mounted on the channel box 15. Tightening the adjustment bolt squeezes the needle tube 14 structure or the needle tube 14 support structure to secure the needle tube 14; loosening the adjustment bolt releases the needle tube 14.

[0078] In this embodiment, when the locking element locks and fixes the needle tube 14, the movable seat 12 can drive the needle tube 14 to move along the first horizontal direction X under the drive of the telescopic mechanism 13; when the locking element releases the fixation of the needle tube 14, the needle tube 14 can move in the adjustment hole, thereby adjusting the relative position of the needle in the first horizontal direction X and / or the second horizontal direction Y, so that the position of the needle and the sample on the sample platform 31 are adapted.

[0079] In one embodiment, the movable base 12 includes a supporting section and connecting blocks constructed at both ends of the supporting section.

[0080] In this embodiment, a receiving groove is formed in the central area of the supporting section along the first horizontal direction X, and a partial structural section of the needle tube 14 is clamped in the receiving groove.

[0081] In this embodiment, the end of each connecting block facing away from the tool holder 32 is fixedly connected to the telescopic mechanism 13, while the end of each connecting block facing the tool holder 32 is fixedly connected to the connecting end. The use of two connecting blocks to form a symmetrical structure connected to the telescopic mechanism 13 ensures smooth movement of the telescopic mechanism 13 and stable and balanced force at the two connecting and fixing locations.

[0082] To achieve the above objectives, the present application also provides a vacuum micro-area charge neutralization system, including the slicer gas injection device of the aforementioned solution.

[0083] In one embodiment, see Figure 5 The vacuum micro-area charge neutralization system also includes a software control unit and a gas quality controller.

[0084] In this embodiment, the software control unit, the gas mass controller and the microtome gas injection device are all installed on the microtome built into the scanning electron microscope.

[0085] The software control unit includes a processor and an operating module external to the scanning electron microscope chamber. The gas mass controller includes a flow valve and is mounted on the gas inlet pipe 4. Specifically, the gas mass controller can be rigidly connected to the vacuum flange on the scanning electron microscope chamber.

[0086] In this embodiment, the gas switch trigger 2 , the gas injection unit 1 and the gas quality controller are all electrically connected to the software control unit.

[0087] In one embodiment, based on the aforementioned embodiment, the software control unit is the hub for controlling the entire gas injection process, and is used to receive electronic signals from the gas switch trigger 2, and send electronic signals to the gas quality controller and the gas injection unit 1, to achieve automatic gas injection opening and closing actions, thereby reducing the total amount of gas injection over a long period of time.

[0088] The staff can use the operation module to adjust the electronic signal sent by the software control unit, thereby accurately controlling and adjusting the actions of the gas quality controller and the gas injection unit 1.

[0089] Furthermore, the gas mass controller is a functional component that realizes gas flow regulation and gas path opening and closing. By receiving signals from the software control unit, it realizes high-precision, ultra-micro-precision control of the gas in the gas path, and at the same time has the function of a gas path switch.

[0090] When the gas switch trigger 2 senses the slicing action of the slicer, the gas switch trigger 2 sends an action signal to the software control unit; after receiving the action signal, the software control unit sends signals to the gas mass controller and the gas injection unit 1 respectively, activating the gas mass controller to open the gas path of the air inlet pipe 4, and at the same time the gas injection unit 1 moves to adjust the gas injection position of the needle.

[0091] When the tool holder 32 loses contact with the gas switch trigger 2, the gas switch trigger 2 sends a reset signal to the software control unit; after receiving the reset signal, the software control unit sends corresponding signals to the gas mass controller and the gas injection unit 1 respectively, and the gas mass controller closes the gas path of the air inlet pipe 4, while the gas injection unit 1 drives the needle tube 14 to reset and move.

[0092] When adjusting the gas flow in the intake pipe 4, the staff uses the operation module to control the software control unit to send a corresponding adjustment electronic signal to the gas quality controller, and the gas quality controller adjusts the opening of the valve component in the intake pipe 4 accordingly.

[0093] During operation, the sample is placed on the sample platform 31 and the scanning electron microscope is started. First, the microtome 3 works, and the microtome cuts at a preset angle and position. At the same time, the knife holder 32 and the sample platform 31 are advanced along the first horizontal direction X, and the microtome cuts a thin slice of the sample from the sample with its sharp blade; during the advancement of the knife holder 32 and the sample platform 31, the knife holder 32 will contact the contact piece 322, that is, the gas switch trigger 2 senses the slicing action and feeds back an action signal to the software control unit. After receiving the signal, the software control unit synchronously sends a signal to the gas mass controller and the gas injection unit 1; the gas injection The input unit 1 activates the telescopic mechanism 13 to drive the movable seat 12 to move, thereby causing the needle tube 14 and the sample platform 31 to move synchronously and cooperatively, ensuring that the needle can accurately inject gas into the sample slice; the gas mass controller opens the air path of the air inlet pipe 4, and air enters the needle tube 14 from the air inlet pipe 4 and accurately inflates the sample slice through the needle; finally, the scanning electron microscope releases an electron beam to irradiate the sample slice. At this time, the electron beam will react with the nitrogen gas mass injected into the air to form positively charged ions. The ions sputter on the sample surface to neutralize the negatively charged electrons, eliminating the charging effect and completing high-quality and high-stability image acquisition.

[0094] Accordingly, when the microtome knife, knife holder 32, and sample platform 31 are reset, the knife holder 32 separates from the contact piece 322. The gas switch trigger 2 senses the reset action and sends a reset signal to the software control unit. Upon receiving the signal, the software control unit synchronously sends signals to the gas mass controller and gas injection unit 1. The gas injection unit 1 controls the telescopic mechanism 13 to reverse, thereby driving the movable seat 12 and needle tube 14 to reset. The gas mass controller closes the air path of the air inlet pipe 4, and the needle tube 14 stops supplying gas to the sample area, maintaining the vacuum working environment within the scanning electron microscope cavity. Thus, a single section imaging process is completed through sectioning, gas injection, and imaging. By repeating this process, efficient and continuous three-dimensional continuous section imaging can be achieved.

[0095] In summary, the microtome gas injection device and vacuum micro-area charge neutralization system of the present application can eliminate the charging effect of the local area with a minimum amount of gas introduced while maintaining a high vacuum environment, without interfering with the electron beam or the signal electrons of the sample, thereby retaining the image quality to the greatest extent. Under this system, biological samples can obtain long-term, stable, continuous or high-quality image data without any conductive treatment, and the whole process can be executed automatically without human intervention. Depending on the type, size and characteristics of the sample, the amount of gas introduced and the corresponding execution imaging can be manually adjusted and retained, thereby achieving a more accurate, efficient and automated control process.

[0096] The above are only optional embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A microtome gas injection device, the device being installed on a microtome built into a scanning electron microscope, characterized in that: Including a gas injection unit and a gas switch trigger; The gas injection unit includes a holder, a movable holder, a telescopic mechanism, and a needle tube; the holder is fixedly connected to the microtome, and the movable holder is fixedly connected to the holder via the telescopic mechanism; the needle tube is clamped on the movable holder, and one end of the needle tube is connected to the air inlet pipe, and the other end of the needle tube extends to the sample platform of the microtome; The gas switch trigger includes a contact plate, the two ends of which are a connecting end and a triggering end, the connecting end is fixedly connected to the movable base; the triggering end faces the blade holder of the slicer and is used to sense the slicing action of the slicer; The slicer performs a slicing action, driving the sample platform and the knife holder to move along the first horizontal direction, causing the knife holder to contact the trigger end, thereby activating the telescopic mechanism to drive the movable base to move along the first horizontal direction. The movable base carries the needle tube to move in coordination with the sample platform. At the same time, the air inlet pipe supplies air, and the needle tube injects gas into the sample on the sample platform.

2. The gas injection device for a slicer according to claim 1, characterized in that: The trigger end is provided with a contact element; When the microtome performs a slicing action, the knife holder moves along the first horizontal direction and contacts the contact element, activating the gas injection unit, and the telescopic mechanism drives the movable seat to move away from the sample platform and opens the gas path of the air inlet pipe; When a single slicing action of the microtome is completed, the knife holder and the sample platform retreat and reset, the contact element separates from the knife holder, the telescopic mechanism drives the movable seat to move toward the sample platform and reset, and closes the air path of the air inlet pipe; The contact element can also adjust its relative position along the first horizontal direction, thereby adjusting the response speed of the gas switch trigger to the slicing action.

3. The gas injection device for a slicer according to claim 2, characterized in that: An insulating plate is provided on the end surface of the tool holder adjacent to the trigger end, and a contact piece is provided on the side of the insulating plate facing away from the tool holder; When the slicer performs a slicing action and drives the knife holder to move, the contact piece contacts the contact element.

4. The gas injection device for a slicer according to claim 3, characterized in that: The gas switch trigger also includes a collision plate; The collision plate and the contact plate are symmetrically arranged along the second horizontal direction, and the collision plate and the contact plate are respectively detachably fixedly connected to the movable seat; When the slicer performs a slicing action, when the knife holder moves along the first horizontal direction, the knife holder contacts the collision plate and the contact element at the same time, or the knife holder contacts the contact element first.

5. The gas injection device for a slicer according to claim 1, characterized in that: The gas injection unit further includes a channel box; The channel box is fixedly connected to the movable seat; the channel box has an adjustment hole along a first horizontal direction, and the diameter of the adjustment hole is larger than the outer diameter of the needle tube; a partial structural section of the needle tube passes through the adjustment hole; The channel box is also provided with a locking element; the locking element extends inwardly from the outer end surface of the channel box into the adjustment hole, and the locking element can movably fix the needle tube; When the locking element locks and fixes the needle tube, the movable seat can drive the needle tube to move along the first horizontal direction under the drive of the telescopic mechanism; When the locking element releases the fixation of the needle tube, the needle tube can move in the adjustment hole, thereby adjusting the relative position of the needle in the first horizontal direction and / or the second horizontal direction, so that the position of the needle and the sample on the sample platform are adapted.

6. The gas injection device for a slicer according to claim 1, characterized in that: The movable base includes a supporting section and connecting blocks constructed at both ends of the supporting section; A receiving groove is formed in the central area of the support section along a first horizontal direction, and a partial structural section of the needle tube is clamped in the receiving groove; One end of each connecting block facing away from the tool holder is fixedly connected to the telescopic mechanism, and one end of each connecting block facing the tool holder is fixedly connected to the connecting end.

7. A vacuum micro-area charge neutralization system, characterized in that: The device comprises a microtome gas injection device according to any one of claims 1 to 6.

8. The vacuum micro-area charge neutralization system according to claim 7, characterized in that: Also included are a software control unit and a gas quality controller; The software control unit, the gas quality controller and the microtome gas injection device are all installed on the microtome built into the scanning electron microscope; The software control unit comprises a processor and an operation module externally mounted on the scanning electron microscope cavity; the gas mass controller comprises a flow valve, and the gas mass controller is mounted on the air inlet pipe; The gas switch trigger, the gas injection unit and the gas quality controller are all electrically connected to the software control unit.

9. The vacuum micro-area charge neutralization system according to claim 8, characterized in that: The software control unit is used to receive the electronic signal sent by the gas switch trigger, and send electronic signals to the gas quality controller and the gas injection unit; The staff can use the operation module to adjust the electronic signal sent by the software control unit, thereby controlling and adjusting the actions of the gas quality controller and the gas injection unit.

10. The vacuum micro-area charge neutralization system according to claim 9, characterized in that: The gas quality controller is a functional component that realizes gas flow regulation and gas circuit opening and closing; When the gas switch trigger senses the slicing action of the microtome, the gas switch trigger sends an action signal to the software control unit; after receiving the action signal, the software control unit sends signals to the gas mass controller and the gas injection unit respectively, activating the gas mass controller to open the gas path of the gas inlet pipe, and at the same time, the gas injection unit moves to adjust the gas injection position of the needle; When the tool holder is disconnected from the gas switch trigger, the gas switch trigger sends a reset signal to the software control unit; after receiving the reset signal, the software control unit sends corresponding signals to the gas mass controller and the gas injection unit respectively, and the gas mass controller closes the gas path of the air inlet pipe, while the gas injection unit drives the needle tube to reset and move; When adjusting the gas flow rate of the intake pipe, the staff uses the operation module to control the software control unit to send a corresponding adjustment electronic signal to the gas mass controller, and the gas mass controller adjusts the opening of the valve component in the intake pipe accordingly.

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