Atomic cell packaging structure and optically pumped magnetometer for realizing high-density optically pumped magnetometer magnetoencephalography device

Abstract

The application provides an atomic gas chamber packaging structure and an optically pumped magnetometer for realizing a high-density optically pumped magnetometer magnetoencephalography device, and relates to the field of magnetoencephalography imaging. The packaging structure comprises a vacuum closed shell, an atomic gas chamber and a heating unit. The vacuum closed shell comprises a main body structure and a cover plate, forms a low-emission high-vacuum sealed cavity, and the atomic gas chamber is arranged in the cavity. The problems of power consumption and heat dissipation of the atomic gas chamber are effectively solved, and the problems of thermal failure and high surface temperature are solved, so that the optically pumped magnetometer magnetoencephalography device with higher channel density is realized. The cover plate comprises a first through hole, and an exhaust pipe is detachably connected to the first through hole and communicates with the vacuum sealed cavity. After being exhausted, the first through hole is sealed, and the low-emission of the high-vacuum sealed cavity is further ensured. The atomic gas chamber is heated and temperature-controlled by a heating resistor, so that the atomic gas chamber can be precisely and efficiently heated and temperature-controlled. Compared with the heating and temperature-controlling mode of absorbing laser, the power consumption is effectively reduced.

Description

Technical Field

[0001] This application relates to the field of magnetoencephalography (MEG) imaging technology, and in particular to an atomic gas cell encapsulation structure and a magnetoencephalography device that realizes a high-density optically pumped magnetometer. Background Technology

[0002] Magnetoencephalography (MEG) is a non-invasive brain imaging technique that records and locates brain activity in real time by measuring the extremely weak magnetic fields generated by the synchronous firing of neurons in the brain. Atomic magnetometers or optically pumped magnetometers (OPMs) can detect magnetic fields and determine their characteristics. Currently, OPMs used in MEG are mainly based on the spin-exchange relaxation-free (SERF) mechanism. Under conditions of high atomic density and near-zero magnetic field, extremely rapid spin-exchange collisions between atoms quickly average the precession phase of different atomic spins, preventing spin exchange from causing decoherence and thus significantly extending the spin coherence time, maintaining sensitivity to external magnetic fields.

[0003] OPM based on the SERF mechanism typically comprises a physical component consisting of optics, a light source, and atomic or molecular materials. This physical component is powered and operated by a controller, which processes signals from the physical component. Inside the physical component, atomic or molecular materials (such as alkali metal vapor) are enclosed in atomic chambers and heated to approximately 150°C to achieve optimal saturated vapor pressure and high atomic density. Subsequently, alkali metal atoms are optically pumped using a laser, causing them to spin polarize and become highly sensitive to weak external magnetic fields. When the magnetic field generated by brain neural activity alters the atomic spin, it induces a change in the optical signal; that is, the brain magnetic field is detected and its characteristics determined, thereby enabling non-invasive reconstruction of brain magnetic signals.

[0004] However, heating and maintaining the atomic gas chamber requires a significant amount of electricity (typically around 1W for a miniaturized OPM's atomic gas chamber). This high current introduces substantial external magnetic field interference, affecting the detection of brain magnetic field signals. Furthermore, the high temperature of the atomic gas chamber (up to approximately 150°C, as mentioned above) also raises the surface temperature of the detector to about 54°C. In biomagnetic measurements (such as brain magnetic fields), this can cause discomfort or even burning pain for the user, affecting experiments and potentially triggering pain-induced interference signals. Increasing the distance between the atomic gas chamber and the user's scalp, however, attenuates the measured brain magnetic field signal, reducing the signal-to-noise ratio and affecting the accuracy of MEG. For example, the brain magnetic field signal generated in the motor cortex is approximately 15mm from the scalp, while the distance between the atomic gas chamber of current commercial OPMs and the scalp is greater than 6mm, which is highly detrimental to the detection of brain magnetic field signals.

[0005] Currently, the highest number of detector sites in commonly used optically pumped magnetometers (OPM-MEG) is 128. The channel density (corresponding to the number of detector sites) of the OPM array cannot be increased further, mainly due to the power consumption and temperature of the atomic gas cell. In addition, the heat generated by the high-density OPM array will cause it to fail due to high temperature and significantly increase the power supply pressure. Summary of the Invention

[0006] In view of this, this application provides an atomic gas cell encapsulation structure and an optically pumped magnetometer for realizing a high-density optically pumped magnetoencephalography (MEG) device, as follows:

[0007] An atomic gas chamber encapsulation structure for realizing a high-density optically pumped magnetometer magnetoencephalography (MEG) device, the encapsulation structure comprising: a vacuum-sealed housing, an atomic gas chamber, and a heating unit, wherein the atomic gas chamber is placed in the vacuum-sealed cavity of the vacuum-sealed housing;

[0008] The vacuum-sealed housing includes a main structure and a cover plate. The main structure and the cover plate seal to form the vacuum-sealed cavity. The cover plate includes a first through hole and a vacuum pipe. The vacuum pipe is detachably connected to the first through hole and communicates with the vacuum-sealed cavity through the first through hole. During the preparation of the packaging structure, the vacuum pipe is connected to an external vacuum device through a heating and melting process to achieve vacuuming of the vacuum-sealed cavity and control the vacuum degree of the vacuum-sealed cavity to be no less than a first preset value. After the packaging structure is completed, the vacuum pipe is removed, and the first through hole is sealed.

[0009] The heating unit includes a heating resistor, which is placed outside the atomic gas chamber and is used to heat and maintain the atomic gas chamber to a preset temperature. The cover plate also includes a second through hole, through which the wire of the heating resistor is electrically connected to an external power supply terminal to provide an electrical signal to the heating resistor.

[0010] Optionally, the first preset value is not greater than 10. -3 pa.

[0011] Optionally, the heating unit includes a first heating resistor and a second heating resistor, which are respectively disposed on opposite sides of the atomic gas chamber.

[0012] Optionally, the first heating resistor and the second heating resistor cover one side of the main body structure; or,

[0013] The first heating resistor and the second heating resistor cover a portion of the area on one side of the atomic gas chamber.

[0014] Optionally, the packaging structure further includes a support assembly placed in the vacuum-sealed cavity, and the atomic gas chamber placed on the support assembly;

[0015] The support assembly includes a first support assembly and a second support assembly, the second support assembly being located on one side of the first support assembly, and the atomic gas chamber being disposed on the side of the second support assembly away from the first support assembly;

[0016] The first support component is a hollow structure, the atomic gas chamber corresponds to the hollow region of the first support component, and the hollow region of the first support component is connected to the vacuum sealing cavity.

[0017] Optionally, the second support assembly includes a first line support assembly arranged along a first direction, the atomic gas chamber being disposed on the side of the first line support assembly away from the first support assembly, and along a direction perpendicular to the plane of the support assembly, the projected width of the first line support assembly is smaller than the projected width of the atomic gas chamber; and / or,

[0018] The second support component includes a second line support component arranged along a second direction. The atomic gas chamber is disposed on the side of the first line support component and the second line support component away from the first support component. Along a direction perpendicular to the plane where the support component is located, the projected width of the second line support component is smaller than the projected width of the atomic gas chamber.

[0019] Wherein, the first direction is parallel to the plane where the support component is located, and the projected width of the first line support component and the projected width of the atomic gas chamber are the widths along the first direction; the second direction is parallel to the plane where the support component is located, and the second direction intersects the first direction, and the projected width of the second line support component and the projected width of the atomic gas chamber are the widths along the first direction.

[0020] Optionally, the second support assembly includes a thin film support assembly, and the atomic gas chamber is disposed on the side of the thin film support assembly away from the first support assembly;

[0021] Along a direction perpendicular to the plane where the support component is located, the projection of the atomic gas cell is located in the projection of the thin film support component, and the thickness of the thin film support component is not greater than a second preset value.

[0022] Optionally, the second preset value is no greater than 50 μm.

[0023] Optionally, the encapsulation structure further includes a heat radiation reflective layer, which is disposed on the inner side of the main structure;

[0024] The main structure includes multiple sides that surround the vacuum-sealed cavity, and the thermal radiation reflective layer is disposed on the inner side of at least one of the multiple sides, and the thermal radiation reflective layer covers a portion of the area of ​​the side on which it is located; wherein, the polarized beam of the atomic gas chamber is transmitted to the atomic gas chamber through the area not covered by the thermal radiation reflective layer.

[0025] A light-pumped magnetometer for realizing a high-density magnetoencephalography (MEG) device includes: an atomic gas cell encapsulation structure, a laser source, a circular polarizer, a reflector, and a photoelectric converter;

[0026] The laser source emits a laser beam, which is transmitted sequentially through the circular polarizer and the mirror to the atomic gas cell encapsulation structure to generate a detection beam. The photoelectric converter generates a detection signal based on the detection beam, and the detection signal is used to realize magnetoencephalography (MEG) imaging.

[0027] The atomic gas chamber encapsulation structure is the atomic gas chamber encapsulation structure described in any of the above embodiments.

[0028] Compared with related technologies, the beneficial effects of the technical solution of this application are as follows:

[0029] The encapsulation structure includes a vacuum-sealed housing, an atomic gas chamber, and a heating unit. The vacuum-sealed housing comprises a main structure and a cover plate. The main structure and the cover plate seal together to form a high-vacuum-density sealed cavity with a low gas release rate. The atomic gas chamber is placed within this vacuum-sealed cavity. The cover plate includes a first through-hole. The vacuum-sealed housing also includes a vacuum extraction pipe, which is detachably connected to the first through-hole and communicates with the vacuum-sealed cavity through the first through-hole. The pipe is removed after the vacuum-sealed cavity is evacuated, and the first through-hole is sealed after evacuation. The heating unit includes a heating resistor, which is placed on the outside of the atomic gas chamber, specifically attached to the outside of the atomic gas chamber, and is used to heat and maintain the atomic gas chamber at a preset temperature. Therefore, this encapsulation structure forms a high-vacuum-density sealed cavity with a low gas release rate during assembly, and the atomic gas chamber is placed within this vacuum-sealed cavity. This suppresses external heat transfer from the atomic gas chamber, effectively solving the power consumption and heat dissipation problems of the atomic gas chamber. This effectively solves a series of problems caused by the power consumption and heat dissipation of the atomic gas chamber, ultimately enabling higher channel density in the optically pumped magnetometer magnetoencephalography (MEG) device and improving measurement accuracy. Furthermore, the aforementioned vacuum-sealed cavity with low gas release rate is formed during the packaging structure preparation process, and does not need to be generated and maintained during subsequent actual use, which simplifies the actual operation of the optical pump magnetometer based on this packaging structure, and thus facilitates practical applications.

[0030] Furthermore, the atomic gas chamber is heated and maintained at its temperature using heating resistors, enabling precise and efficient heating and temperature control. Compared to heating and temperature control methods such as laser absorption, this approach offers higher heating and temperature control efficiency and effectively reduces power consumption. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0032] The structures, proportions, sizes, etc., shown in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this application. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0033] Figure 1 A schematic diagram of an atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetometer magnetoencephalography (MEG) device is provided in this application;

[0034] Figure 2 This is a schematic diagram of the structure of a vacuum-sealed shell;

[0035] Figure 3 Sensitivity curves for an atomic gas cell encapsulation structure for a high-density optically pumped magnetometer magnetoencephalography (MEG) device based on this application;

[0036] Figure 4 A schematic diagram of an atomic gas cell encapsulation structure for another high-density optically pumped magnetometer magnetoencephalography (MEG) device provided in this application;

[0037] Figure 5 A schematic diagram of an atomic gas cell encapsulation structure for another high-density optically pumped magnetometer magnetoencephalography (MEG) device provided in this application;

[0038] Figure 6 A schematic diagram of an atomic gas cell encapsulation structure for another high-density optically pumped magnetometer magnetoencephalography (MEG) device provided in this application;

[0039] Figure 7 A schematic diagram of an atomic gas cell encapsulation structure for another high-density optically pumped magnetometer magnetoencephalography (MEG) device provided in this application;

[0040] Figure 8 A comparison diagram of the heating power of an atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetometer magnetoencephalography device provided in this application;

[0041] Figure 9 This application provides a schematic diagram of the structure of an optically pumped magnetometer for a high-density magnetoencephalography (MEG) device. Detailed Implementation

[0042] The embodiments of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0043] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] As described in the background section, the heating and temperature maintenance of the atomic gas cell introduces significant external magnetic field interference and leads to high surface temperatures in the optically pumped magnetometer magnetoencephalography (MEG) device, affecting testing performance and accuracy. Furthermore, it limits the channel density of the MEG device and can cause thermal failure. Therefore, suppressing and blocking heat transfer from the atomic gas cell to reduce power consumption and surface temperature is an effective approach for the development and widespread adoption of optically pumped magnetoencephalography.

[0045] Based on this, this application provides an atomic gas cell 200 packaging structure for realizing a high-density optically pumped magnetometer magnetoencephalography (MEG) device, such as... Figure 1 As shown, Figure 1 This application provides a schematic diagram of the encapsulation structure for an atomic gas chamber 200 in a high-density optically pumped magnetometer magnetoencephalography (MEG) device. The encapsulation structure includes a vacuum-sealed housing 100, an atomic gas chamber 200, and a heating unit 300. The atomic gas chamber 200 is placed within the vacuum-sealed cavity of the vacuum-sealed housing 100. Atomic or molecular materials (such as alkali metal vapor) are sealed inside the atomic gas chamber 200.

[0046] like Figure 2 As shown, Figure 2 This is a schematic diagram of the structure of a vacuum-sealed housing 100. The vacuum-sealed housing 100 includes a main structure 102 and a cover plate 104, which are sealed together to form a vacuum-sealed cavity. The cover plate 104 includes a first through hole 106. The vacuum-sealed housing 100 also includes a vacuum extraction pipe 108, which is detachably connected to the first through hole 106 and communicates with the vacuum-sealed cavity through the first through hole 106. During the fabrication or assembly process of the encapsulation structure, the vacuum extraction pipe 108 is connected to an external vacuum extraction device through a heating and melting process to achieve vacuuming of the vacuum-sealed cavity and control the vacuum level of the vacuum-sealed cavity to be no less than a first preset value. After the encapsulation structure is fabricated, the vacuum extraction pipe 108 is removed or melted and sealed at the first through hole 106. During and after the fabrication of the encapsulation structure, the first through hole 106 is in a sealed state to maintain the vacuum state of the vacuum-sealed cavity. However, it should be understood that the aforementioned first through-hole 106 being in a sealed state refers to the fact that during the fabrication of the encapsulation structure, the first through-hole 106 is sealed to the vacuum tube 108. After the encapsulation structure is completed, the vacuum tube 108 is removed, and the first through-hole 106 can be sealed with sealant. Alternatively, this encapsulation structure can also achieve a high-vacuum sealed cavity without using the vacuum tube 108 to evacuate the sealed shell, instead achieving a vacuum level of less than 10... -3The assembly is performed directly in a vacuum environment of Pa, and after assembly, a high-vacuum vacuum-sealed cavity for the encapsulation structure can be achieved. Accordingly, the cover plate 104 does not include the first through hole 106 and the evacuation pipe 108 at this time.

[0047] Continuing, for example Figure 2 As shown, the main structure 102 can be a hollow structure with five integrated surfaces, and the main structure 102 is sealed to the cover plate 104 by a low-release epoxy resin adhesive, etc. The first through hole 106 can also be sealed by a low-release epoxy resin adhesive, etc. The specific sealing process can be as follows: apply epoxy resin adhesive directly to the joint and contact gap between the main structure 102 and the cover plate 104 to seal all joints between the main structure 102 and the cover plate 104 to prevent air leakage; then, the cover plate 104 is embedded into the main structure 102 as a whole, and epoxy resin adhesive is poured to fill the area except for the cover plate 104 to achieve vacuum sealing of the vacuum-sealed shell 100, thereby achieving a vacuum-sealed cavity with an extremely low release rate. It should be noted that, in order to ensure the airtightness of the vacuum sealing cavity before, during, and after vacuuming, the main structure 102 can be made of light-transmitting materials with extremely low gas release rates, such as glass or quartz. The cover plate 104 can be made of ceramic, glass, quartz, plastic with low gas release rates, etc., and the suction pipe 108 can be made of materials that can be heated and melted, such as glass.

[0048] Alternatively, the sealing between the main structure 102 and the cover plate 104 of the vacuum-sealed housing 100 can also employ other processes, such as femtosecond laser technology. Utilizing the short duration and high power of laser light, the main structure 102 and cover plate 104 are fused together, achieving vacuum encapsulation with extremely low gas release rates. Another method is vacuum reflow soldering, where metallized pads are built on the surfaces of the main structure 102 and cover plate 104, and reflow soldering or vacuum reflow soldering is used to weld and seal the main structure 102 and cover plate 104, achieving vacuum encapsulation with extremely low gas release rates. Since the maximum withstand temperatures of the welding points between the atomic gas chamber 200 and the heating unit 300 are 200°C and 300°C respectively, during the sealing process, the overall structural temperature must be kept below 200°C throughout, and the short-term temperature at the sealing surface of the encapsulated structure must not exceed 300°C. Furthermore, AC induction heating cannot be used during the sealing welding process, as a large alternating magnetic field may magnetize or even damage the heating circuit and components of the internal heating unit 300. In addition, eutectic welding methods such as ultrasonic welding can be used during the welding process to ensure that heat is confined only to the welding surface. It is important to note that if solder is used, the solder melting point must be above 200℃ and below 300℃. If the solder melting point is too low, the high temperature of the molten glass during the sealing of the vacuum tube 108 may be transferred to the weld point, causing vacuum sealing welding failure. If the solder melting point is too high, the overall structure may exceed the safe temperature range, leading to structural failure. If adhesive methods are used, the curing temperature of the epoxy resin must be below 200℃, and the complete curing time must be less than 1 hour to minimize the impact on the internal structure. If femtosecond laser welding is used, the welding time must be strictly controlled, and the temperature at the weld point must be below 200℃ and the temperature of the vacuum sealing chamber below 300℃ during the welding process.

[0049] During the fabrication of the encapsulation structure, each part of the vacuum-sealed shell 100 is placed on a vacuum pumping platform (external pumping device) and thoroughly baked to remove adhering gases from the structural surfaces and release gases from the material itself. After the structures to be placed in the vacuum-sealed cavity (e.g., atomic gas chamber 200, heating unit 300, support components described later) have been placed in the hollow area of ​​the main structure 102, the main structure 102 is sealed to the cover plate 104. Then, by heating and melting the pumping pipe 108, the vacuum-sealed cavity is airtightly connected to the vacuum pumping platform through the pumping pipe 108. A vacuum pump is then used to evacuate the vacuum-sealed cavity, so that the theoretical vacuum degree of the vacuum-sealed cavity can reach 10. -6 This allows for the creation of a high-vacuum vacuum sealing cavity. Furthermore, during the vacuuming process, the vacuum level of the vacuum sealing cavity can be controlled using the vacuum pumping platform, enabling flexible control of the vacuum level. This makes it suitable for a wider range of applications and demonstrates strong practicality.

[0050] Based on the relationship between the thermal conductivity of air and pressure, it can be known that when the pressure inside a vacuum-sealed cavity reaches 10... -3 Below a pressure of Pa, heat convection and conduction caused by air within the vacuum-sealed cavity can be suppressed, thus effectively blocking external heat transfer from the atomic gas chamber 200. Therefore, this encapsulation structure effectively blocks external heat transfer from the atomic gas chamber 200, significantly reducing the power consumption required for heating and maintaining its temperature. It eliminates the need for large currents required for heating and maintaining the atomic gas chamber 200, preventing significant external magnetic field interference and ensuring measurement accuracy. Furthermore, with heat dissipation effectively isolated by the high-vacuum environment, the time required for the atomic gas chamber 200 to reach the preset temperature and the equilibrium time of the internal temperature field are greatly shortened, allowing for faster entry into the magnetoencephalography (MEG) measurement phase and improving work efficiency.

[0051] Furthermore, this packaging structure effectively blocks external heat transfer from the atomic gas chamber 200 and reduces the surface temperature of the detector in the high-density integrated optically pumped magnetometer magnetoencephalography (OPM) device, even below body temperature. This effectively prevents user discomfort due to excessively high device surface temperature, thus avoiding impacts on experimental performance and measurement accuracy. Simultaneously, this packaging structure suppresses external heat transfer from the atomic gas chamber 200 and reduces its power consumption, significantly inhibiting high-temperature thermal failure of the high-density OPM magnetoencephalography (EDA) device. Therefore, this packaging structure can support the implementation of high-density OPM magnetoencephalography (EDA) devices, i.e., devices with high-density OPM arrays at room temperature, thereby greatly improving source tracing accuracy, signal localization accuracy, and ensuring measurement precision. Specifically, as shown in... Figure 3 As shown, Figure 3 The sensitivity curve of the optically pumped magnetometer probe based on the packaging structure provided in this application is shown. Figure 3 Curves 1 and 2 are sensitivity curves for detecting magnetoencephalogram (MEG) signals using an optically pumped magnetometer based on the packaging structure provided in this application. Figure 3 As can be seen from curves 1 and 2, the sensitivity of the optically pumped magnetometer based on the packaging structure provided in this application is much greater than 10 fT / / Hz. 1 / 2 Therefore, the packaging structure provided in this application can realize the high sensitivity of the optically pumped magnetometer magnetoencephalography device, which helps to improve the measurement accuracy.

[0052] In summary, this encapsulation structure, through a vacuum-sealed shell 100 with a low gas release rate, forms a high-vacuum sealed cavity surrounding the atomic gas chamber 200 during the encapsulation structure fabrication process. This suppresses external heat transfer from the atomic gas chamber 200, effectively solving the power consumption and heat dissipation problems of the atomic gas chamber 200. Consequently, it effectively addresses a series of issues caused by the power consumption and heat dissipation of the atomic gas chamber 200, ultimately enabling higher channel density in the optically pumped magnetometer magnetoencephalography (MEG) device. Furthermore, the temperature of the area close to the user's scalp can remain below body temperature, improving measurement accuracy. Moreover, the aforementioned low-gas-release rate vacuum sealed cavity is formed during the encapsulation structure fabrication process and does not require subsequent generation and maintenance during actual use. This simplifies the operation of the high-density optically pumped magnetoencephalography (MEG) device based on this encapsulation structure and reduces the requirements for application scenarios, thus facilitating practical applications.

[0053] like Figure 4 As shown, Figure 4 This application provides a schematic diagram of the encapsulation structure for an atomic gas chamber 200 (vacuum-sealed housing 100 is not shown). The heating unit 300 of this encapsulation structure further includes a heating resistor 302, which is located on the outside of the atomic gas chamber 200, specifically attached to the outside of the atomic gas chamber 200, and is used to heat and maintain the atomic gas chamber 200 to a preset temperature. Figure 1 As shown, the cover plate 104 also includes a second through hole 110. The wire 304 of the heating resistor 302 is electrically connected to the heating resistor 302 through the second through hole 110, providing an electrical signal to the heating resistor 302, i.e., supplying power to the heating resistor 302, so that the heating resistor 302 can heat and maintain the temperature of the atomic gas chamber 200. It should be understood that the heating unit 300 may also include temperature detection elements such as a temperature sensor to achieve precise temperature control of the atomic gas chamber 200. It should be noted that the heating resistor 302 can be fixed to the outside of the atomic gas chamber 200 by bonding or binding with a low-release thermally conductive adhesive.

[0054] As described above, in this packaging structure, the atomic gas chamber 200 is heated and its temperature is maintained by the heating resistor 302, enabling precise and efficient heating and temperature control of the atomic gas chamber 200. Furthermore, the atomic gas chamber 200 in this packaging structure supports resistance heating, which is significantly better than related technologies that use laser absorption for heating and temperature control, indirectly converting electrical power into power consumption, resulting in low conversion efficiency and large size. For example, even assuming all laser power is converted into power consumption, the power required for a DFB or DBR laser is still 100 to 200 times its emitted laser power, resulting in very high power consumption, low heating and temperature control efficiency, and poor practicality. Moreover, even miniaturized DFB or DBR lasers are 3-5 times larger than the detector volume of an optically pumped magnetometer, failing to meet the requirements for detector miniaturization and high-density integration of optically pumped magnetometers in magnetoencephalography (MEG).

[0055] In one embodiment of this application, the first preset value is not greater than 10. -3 pa, meaning the first preset value is less than or equal to 10. -3 pa, up to 10 -6 Pa. However, this application does not limit the specific value of the first preset value, provided that it is not greater than 10. - 3 The purpose of pa is to suppress heat convection and heat conduction caused by air, depending on the specific situation.

[0056] It should be noted that, because the vacuum-sealed cavity of this encapsulation structure can form a vacuum environment that effectively blocks heat convection and heat transfer around the atomic gas chamber 200, and this vacuum environment surrounds the atomic gas chamber 200 within a range of 1mm-2mm, it can effectively suppress heat convection and heat transfer. Therefore, the volume of the vacuum-sealed cavity is greatly reduced, which in turn greatly reduces the volume of the encapsulation structure. This can further reduce the distance between the atomic gas chamber 200 and the user's scalp, for example, to less than 3mm, while the temperature of the area close to the user's scalp is still lower than body temperature, effectively improving measurement accuracy.

[0057] In one embodiment of this application, such as Figure 4 As shown, the heating unit 300 includes a first heating resistor 306 and a second heating resistor 308, which are respectively disposed on opposite sides of the atomic gas chamber 200 and connected in parallel. In other words, the heating resistor 302 in the packaging structure provided in this application is a double-sided cancelling non-magnetic heating resistor. Specifically, the current directions of the first heating resistor 306 and the second heating resistor 308 are opposite, and their magnetic field directions are opposite, thus canceling each other out and effectively achieving zero magnetization of the packaging structure, with residual magnetism less than 0.3 nT. That is, this packaging structure uses a double-sided cancelling non-magnetic heating resistor 302 to heat the atomic gas chamber 200, so that the magnetic fields generated by the currents of the first heating resistor 306 and the second heating resistor 308 located on opposite sides of the atomic gas chamber 200 cancel each other out, achieving non-magnetic heating and avoiding interference with brain magnetic field signal detection.

[0058] It should be noted that the heating current on the first heating resistor 306 and the second heating resistor 308 can use a high-frequency heating signal above 100kHz, so that the AC noise frequency band is far away from the signal frequency band measured by the atomic gas chamber 200 (such as brain magnetic field signal). It should also be noted that since the heating resistor 302 (first heating resistor 306 and second heating resistor 308) and the atomic gas chamber 200 are both located inside the vacuum-sealed cavity, in order to introduce the heating current from the non-vacuum environment to the vacuum environment without damaging the internal vacuum level, the following two methods can be used to lead out the wire 304 of the heating resistor 302. The first method is to use a metallization process on the cover plate 104 to metallize electrodes on both the inner and outer sides of the cover plate 104, and to make the electrodes on both sides conductive using a metallization filling process (second through hole 110). The wire 304 of the heating resistor 302 can then be electrically connected to the electrodes on the inner side of the cover plate 104, thereby realizing the electrical connection with the external power supply terminal. The second method is to directly drill a hole (second through hole 110) in the cover plate 104, and use the wire 304 to be directly led out through the second through hole 110, and seal it with low-release resin glue or metal welding to ensure the airtightness of the vacuum-sealed cavity and prevent the vacuum-sealed cavity from failing. It is important to note that in the metallized electrode, the metal electrode and the transition metal between it and the cover plate 104 must not be ferromagnetic metals (such as iron, cobalt, nickel). The thickness of the metal electrode should be greater than 2 μm and less than 1 mm to ensure sufficient thickness for bonding or welding, while avoiding magnetic noise.

[0059] In another embodiment of this application, such as Figure 4 As shown, the first heating resistor 306 and the second heating resistor 308 cover a portion of one side of the atomic gas chamber 200 where they are located. That is, the first heating resistor 306 and the second heating resistor 308 do not completely cover one side of the atomic gas chamber 200, but rather cover a portion, such as the edge region. Therefore, all sides of the atomic gas chamber 200 can be covered by the first heating resistor 306 and the second heating resistor 308. The polarized beam (e.g., a laser beam) from the atomic gas chamber 200 can be transmitted to the interior of the atomic gas chamber 200 through the area on the side of the atomic gas chamber 200 not covered by the first heating resistor 306 or the second heating resistor 308, optically pumping the alkali metal atoms inside the atomic gas chamber 200 and causing them to spin polarize. It should be noted that, in this embodiment, the heating resistor 302 can be conductively soldered through a second through-hole 110 of a handle structure (i.e., the aforementioned wire 304), wherein the second through-hole 110 is a sealed conductive through-hole.

[0060] In one embodiment of this application, such as Figure 5As shown, the first heating resistor 306 and the second heating resistor 308 cover one side of the atomic gas chamber 200 where they are located, that is, the first heating resistor 306 and the second heating resistor 308 can completely cover the side where they are located, so that the heated area of ​​the atomic gas chamber 200 is large, thereby achieving high heating and temperature control efficiency. However, in order to allow the laser or other polarized beam to be transmitted into the atomic gas chamber 200 and to achieve spin polarization of the alkali metal atoms inside the atomic gas chamber 200, in this embodiment, at least a portion of the side surface of the atomic gas chamber 200 is not covered by the first heating resistor 306 and the second heating resistor 308.

[0061] In one embodiment of this application, such as Figure 4 and Figure 5 As shown, the encapsulation structure also includes a support component 400, which is placed in a vacuum-sealed cavity, and the atomic gas chamber 200 is placed on the support component 400, i.e., the support component 400 is used to support the atomic gas chamber 200. The support component 400 includes a first support component 402 and a second support component 404. The second support component 404 is located on one side of the first support component 402, and the atomic gas chamber 200 is disposed on the side of the second support component 404 away from the first support component 402. The first support component 402 has a hollow structure, the atomic gas chamber 200 corresponds to the hollow region of the first support component 402, and the hollow region of the first support component 402 is connected to the vacuum-sealed cavity.

[0062] As can be seen from the above, the first support component 402 is a hollow structure and is connected to the vacuum sealing cavity. Therefore, the hollow area of ​​the first support component 402 is also a vacuum environment that can suppress heat convection and heat conduction, which can help suppress the external heat conduction of the atomic gas chamber 200 through the first support component 402. Thus, the vacuum environment of the vacuum sealing cavity, combined with the first support component 402, can effectively suppress the external heat conduction of the atomic gas chamber 200 through the first support component 402.

[0063] It should be noted that the first support component 402 is the main support frame for supporting the atomic gas chamber 200. In order to achieve support and ensure the long-term effectiveness of the vacuum inside the vacuum sealing cavity and the normal operation of the detector where the atomic gas chamber is located, the first support component 402 needs to ensure low gas release and non-magnetic properties. The first support component 402 can be made of materials such as ceramics, silicon, glass, quartz, and plastics.

[0064] In one embodiment of this application, such as Figure 6As shown, the second support assembly 404 includes a first line support assembly 406 arranged along a first direction, and an atomic gas chamber 200 disposed on the side of the first line support assembly 406 away from the first support assembly 402. Along a direction perpendicular to the plane of the support assembly 400, the projected width of the first line support assembly 406 is smaller than the projected width of the atomic gas chamber 200; specifically, the projected width of the first line support assembly 406 is much smaller than the projected width of the atomic gas chamber 200, which can also be understood as the projected width of the first line support assembly 406 being much smaller than the projected width of the main structure 102. And / or, the second support assembly 404 includes a second line support assembly 408 arranged along a second direction, and an atomic gas chamber 200 disposed on the side of the first line support assembly 406 and the second line support assembly 408 away from the first support assembly 402. Along a direction perpendicular to the plane of the support component 400, the projected width of the second line support component 408 is smaller than the projected width of the atomic gas chamber 200. Specifically, the projected width of the second line support component 408 is much smaller than the projected width of the atomic gas chamber 200. This can also be understood as the projected width of the second line support component 408 being much smaller than the projected width of the main structure 102. The first direction is parallel to the plane of the support component 400, and the projected widths of the first line support component 406 and the atomic gas chamber 200 are the widths along the first direction. The second direction is parallel to the plane of the support component 400 and intersects (e.g., perpendicular to each other) the first direction. The projected widths of the second line support component 408 and the atomic gas chamber 200 are the widths along the first direction. In other words, the second support component 404 may include the first line support component 406, or the second line support component 408, or both the first line support component 406 and the second line support component 408 (e.g.,...). Figure 6 (As shown).

[0065] The following explanation uses the second support component 404, which includes a first line support component 406 and a second line support component 408, as an example. Specifically, the atomic gas chamber 200 corresponds to the hollow region of the first support component 402. Between the first support component 402 and the atomic gas chamber 200, the first line support components 406 and 408 are arranged in a staggered horizontal direction, ensuring that heat transfer from the atomic gas chamber 200 to the outside is limited to the extending directions of the first line support components 406 and 408. Furthermore, the widths of the first line support components 406 and 408 are much smaller than the width of the side where the atomic gas chamber 200 connects to the support component 400. According to Fourier's law of heat transfer in solids, heat conduction is positively correlated with the heat transfer cross-sectional area. Therefore, the aforementioned first line support components 406 and 408 can effectively reduce heat transfer from the atomic gas chamber 200 to the outside.

[0066] It should be noted that the materials of the first wire support component 406 and the second wire support component 408 can be linear support structures made of non-magnetic metals, alloys, or non-metallic materials, with a diameter of less than 100 μm. The first wire support component 406 and the second wire support component 408 can be woven into a support network above the first support component 402 using welding, bonding, or snap-fit ​​methods. The atomic gas chamber 200 is fixed on the support network formed by the first wire support component 406 and the second wire support component 408, which can achieve stable support for the atomic gas chamber 200 and suppress external heat transfer from the atomic gas chamber 200. It is important to note that a certain preload needs to be applied to the first wire support component 406 and the second wire support component 408 before fixing them to ensure sufficient support rigidity during the installation of the atomic gas chamber 200.

[0067] In one embodiment of this application, the first wire support component 406 and the second wire support component 408 may be low thermal conductivity titanium wires, but this application does not limit this and it depends on the specific circumstances.

[0068] In one embodiment of this application, such as Figure 4 and Figure 5 As shown, the second support assembly 404 includes a thin-film support assembly 410, and the atomic gas chamber 200 is disposed on the side of the thin-film support assembly 410 away from the first support assembly 402. Along a direction perpendicular to the plane of the support assembly 400, the projection of the atomic gas chamber 200 lies within the projection of the thin-film support assembly 410, and the thickness of the thin-film support assembly 410 is no greater than a second preset value. The heat transfer between the atomic gas chamber 200 and the thin-film support assembly 410 below it is also related to the thickness of the thin-film support assembly 410; the smaller the thickness, the weaker the heat transfer between them. Therefore, when the second support assembly 404 below is a thin-film support assembly 410 covering the atomic gas chamber 200, the thickness of the thin-film support assembly 410 should be smaller to reduce the external heat transfer of the atomic gas chamber 200. Before the thin film support assembly 410, the first line support assembly 406 and the second line support assembly 408 are fixed, a certain pre-tightening force needs to be applied to them to ensure that they have sufficient rigidity after fixing. This will prevent the atomic gas cell 200 from tilting or shifting due to wiring, position changes, or other reasons, thus ensuring the stability and collimation of the detection optical axis and ensuring measurement accuracy.

[0069] In one embodiment of this application, the aforementioned second preset value is no greater than 50 μm, meaning the thickness of the aforementioned thin film support component 410 is no greater than 50 μm, and the thermal conductivity of the thin film support component 410 is no greater than 0.35 W / (m*K), which can effectively transfer heat from the atomic gas chamber 200 to the outside. It should be noted that the aforementioned thin film support component 410 can be made of polyimide (PI) material, and can be fixed to the first support component 402 and the atomic gas chamber 200 by means of bonding, welding, or snap-fitting, thereby fixing the atomic gas chamber 200 to the support component 400.

[0070] In one embodiment of this application, the encapsulation structure further includes a thermal radiation reflective layer (not shown in the figure), which is disposed on the inner side of the side of the main body structure 102. The main body structure 102 may include multiple sides that surround the vacuum-sealed cavity. For example, if the main body structure 102 is a hollow structure with five integrated sides, then the multiple sides of the main body structure 102 include four sides and a bottom surface, which surround the vacuum-sealed cavity. Among the multiple sides of the main body structure 102, at least one side has a thermal radiation reflective layer disposed on its inner side, and the thermal radiation reflective layer covers a portion of the area of ​​the side it is located in, for example, covering the area of ​​the side except for the central area. The central area is the location of the light-transmitting aperture of the atomic gas chamber 200, so that the polarized beam of the atomic gas chamber 200 (such as the aforementioned laser polarized beam) is transmitted to the atomic gas chamber 200 through the area not covered by the thermal radiation reflective layer, thereby achieving polarization of the alkali metal atoms in the atomic gas chamber 200. It should be noted that, for the multiple sides mentioned above, the side not used for transmitting the polarized beam can be completely covered by the thermal radiation reflective layer. However, this application does not impose any restrictions on this, and it depends on the specific circumstances.

[0071] Because the thermal radiation reflective layer has high reflectivity in the infrared and far-infrared bands, placing it on the inner side of the main structure 102 can effectively suppress the thermal radiation dissipation of the atomic gas chamber 200, thereby reducing the external heat transfer of the atomic gas chamber 200. It should be noted that the aforementioned thermal radiation reflective layer can be a metal coating, such as gold or platinum, on the inner side of the main structure 102, or it can be an organic coating. It is important to note that if the thermal radiation reflective layer is a metal coating, the thickness of the metal coating must be controlled below 2 μm, and the distance between it and the atomic gas chamber 200 must be greater than 1 mm to ensure that the magnetic noise of the metal coating itself does not affect the atomic gas chamber 200 inside the gas chamber, and also does not shield the modulation magnetic field of the optically pumped magnetometer. It should be noted that this modulation magnetic field is generated and modulated based on the coil 500 described below.

[0072] In one embodiment of this application, a miniaturized optically pumped magnetometer requires magnetic field modulation during measurement, and the coil structure is a crucial component for modulating and compensating the magnetic field. Therefore, the packaging structure may further include Helmholtz coils, dual-plane coils, fingerprint coils, etc., collectively referred to as the magnetic compensation self-calibration modulation coil 500. This coil 500 can be metallized on the outer surface of the main structure 102 and fabricated on a flexible circuit board or a rigid circuit board (e.g., Figure 7 (As shown). Alternatively, the coil 500 can be placed inside a vacuum-sealed cavity (e.g., Figure 2 As shown), it is specifically located inside the main structure 102. However, if the coil is designed inside the vacuum-sealed cavity, conductive metallized pads or wiring holes need to be reserved inside and outside the sealed housing (e.g., on the cover plate 104) so ​​that the signal line 502 of the coil 500 can be led out through the wiring hole to provide an electrical signal to the coil 500.

[0073] In summary, the packaging structure provided in this application enables the miniaturization and demagnetization of the optically pumped magnetometer, eliminating the need for additional magnetic field elimination measures. Specifically, the length and width are less than 10 mm, the height is less than 20 mm, the remanence of the overall structure is less than 0.3 nT, and the sensitivity is better than 10 fT / Hz. 1 / 2 .

[0074] In addition, such as Figure 8 As shown, Figure 8 This is a comparison of the heating power of the packaging structures provided in this application. Curve 1 represents the heating power curve when the vacuum-sealed housing 100 is evacuated, but the support component 400 is not optimized and no heat radiation reflective layer is provided; Curve 2 represents the heating power curve when the vacuum-sealed housing 100 is not evacuated, but the support component 400 is optimized and a heat radiation reflective layer is provided; Curve 3 represents the heating power curve when the vacuum-sealed housing 100 is evacuated, the support component 400 is optimized, but no heat radiation reflective layer is provided; Curve 4 represents the heating power curve when the vacuum-sealed housing 100 is evacuated, the support component 400 is optimized, and a heat radiation reflective layer is provided. According to Figure 8 It is known that the heating power consumption required for heating and maintaining the temperature of the atomic gas chamber 200 in the packaging structure provided in this application is reduced by two orders of magnitude compared with the power consumption of conventional atomic gas chamber packaging designs. In particular, the power consumption for maintaining the temperature of the atomic gas chamber can be considered zero, thereby effectively reducing the heating power required for heating and maintaining the temperature of the atomic gas chamber. Meanwhile, according to... Figure 8 It is also known that as the temperature of the atomic gas chamber 200 increases, the heating power of the atomic gas chamber 200 in the encapsulation structure described in this application hardly increases, or the increase is very small, indicating that the encapsulation structure has a very significant effect on reducing heating power consumption.

[0075] This application also provides an optically pumped magnetometer for implementing high-density magnetoencephalography (MEG) devices, such as... Figure 9 As shown, the optically pumped magnetometer includes an atomic gas cell encapsulation structure 602, a laser source 604, a circular polarizer 606, a reflector 608, and a photoelectric converter 610. The laser source 604 emits a laser beam, which is transmitted sequentially through the circular polarizer 606 and the reflector 608 to the atomic gas cell encapsulation structure 602, generating a detection beam. The photoelectric converter 610 generates a detection signal based on the detection beam, which is used to achieve magnetoencephalography (MEG) imaging. The atomic gas cell encapsulation structure 602 is the encapsulation structure of any of the above embodiments.

[0076] Specifically, the atomic gas chamber 200 in the aforementioned packaging structure 602 is the core component, placed within its zero-power vacuum-sealed cavity. Heated to a certain temperature by the heating resistor 302, the alkali metal atoms within it are vaporized. The alkali metal atoms stored in the atomic gas chamber 200 are emitted by the laser source 604 and sequentially transmitted through the circular polarizer 604 and the reflector 606 to the laser beam pump within the atomic gas chamber 200, where they are spin-polarized. The magnetic compensation self-calibration modulation coil 500 in the packaging structure is responsible for providing the magnetic field modulation signal, magnetic field calibration, and compensation. Magnetic field modulation enables the measurement of multi-axis magnetoencephalography (MEG) signals, magnetic field calibration calibrates the measured MEG signals in standard units, and the compensation magnetic field further reduces the static magnetic field strength of the gas chamber within the magnetically shielded environment. The photoelectric converter 608 (e.g., a photodiode) converts the acquired optical signal into an electrical signal (i.e., a detection signal), which is then transmitted to the subsequent data acquisition and processing system to achieve MEG imaging.

[0077] It should be noted that this application does not limit the specific structure of the high-density integrated optically pumped magnetometer magnetoencephalography (MEG) device used in the atomic gas chamber encapsulation structure. The above embodiment is only one application embodiment and is not a limitation on the high-density integrated optically pumped magnetometer MEG device used in the encapsulation structure. The specific implementation depends on the circumstances.

[0078] In summary, this application provides an atomic gas cell encapsulation structure and an optically pumped magnetometer for realizing a high-density optically pumped magnetoencephalography (MEG) device. The encapsulation structure includes a vacuum-sealed housing, an atomic gas cell, and a heating unit. The vacuum-sealed housing includes a main structure and a cover plate. The main structure and the cover plate are sealed together to form a high-vacuum sealed cavity with a low gas release rate. The atomic gas cell is placed within this vacuum-sealed cavity. The cover plate includes a first through-hole. The vacuum-sealed housing also includes a vacuum extraction pipe, which is detachably connected to the first through-hole, communicates with the vacuum-sealed cavity through the first through-hole, and is removed after the vacuum-sealed cavity is evacuated. The first through-hole is then sealed. The heating unit includes a heating resistor, which is placed on the outside of the atomic gas cell, specifically attached to the outside of the atomic gas cell, for heating and maintaining the atomic gas cell at a preset temperature. Therefore, this packaging structure forms a high-vacuum sealed cavity with a low gas release rate during assembly, and the atomic gas cell is placed in this vacuum sealed cavity. This suppresses the external heat transfer of the atomic gas cell, effectively solving the power consumption and heat dissipation problems of the atomic gas cell. This, in turn, effectively solves a series of problems caused by the power consumption and heat dissipation of the atomic gas cell, ultimately enabling higher channel density and improved measurement accuracy in optically pumped magnetoencephalography (OEEG) devices. Furthermore, the aforementioned vacuum sealed cavity with a low gas release rate is formed during the packaging structure fabrication process, and does not need to be generated or maintained during subsequent actual use, which is beneficial for the practical application of OEEG devices based on this packaging structure.

[0079] Furthermore, the atomic gas chamber is heated and maintained at its temperature via a heating resistor, enabling precise and efficient heating and temperature control, reaching the designated temperature more quickly. Compared to heating and temperature control methods such as laser absorption, this method offers higher heating and temperature control efficiency, effectively reducing power consumption and improving measurement efficiency.

[0080] The various embodiments in this specification are described in a progressive, parallel, or combined manner. Each embodiment focuses on its differences from other embodiments, and similar or identical parts between embodiments can be referred to interchangeably. For the apparatuses disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0081] It should be noted that, in the description of this application, the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. When a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component centrally located at the same time.

[0082] It should also be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or apparatus comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or apparatus that includes the aforementioned element.

[0083] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetoencephalography (MEG) device, characterized in that, The encapsulation structure includes: a vacuum-sealed housing, an atomic gas chamber, and a heating unit, wherein the atomic gas chamber is placed in the vacuum-sealed cavity of the vacuum-sealed housing; The vacuum-sealed housing includes a main structure and a cover plate. The main structure and the cover plate seal to form the vacuum-sealed cavity. The cover plate includes a first through hole and a vacuum pipe. The vacuum pipe is detachably connected to the first through hole and communicates with the vacuum-sealed cavity through the first through hole. During the preparation of the packaging structure, the vacuum pipe is connected to an external vacuum device through a heating and melting process to achieve vacuuming of the vacuum-sealed cavity and control the vacuum degree of the vacuum-sealed cavity to be no less than a first preset value. After the packaging structure is completed, the vacuum pipe is removed, and the first through hole is sealed. The heating unit includes a heating resistor, which is placed outside the atomic gas chamber and is used to heat and maintain the atomic gas chamber to a preset temperature. The cover plate also includes a second through hole, through which the wire of the heating resistor is electrically connected to an external power supply terminal to provide an electrical signal to the heating resistor.

2. The atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetoencephalography (MEG) device according to claim 1, characterized in that, The first preset value is no greater than 10 -3 pa.

3. The atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetoencephalography (MEG) device according to claim 1, characterized in that, The heating unit includes a first heating resistor and a second heating resistor, which are respectively disposed on opposite sides of the atomic gas chamber.

4. The atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetoencephalography (MEG) device according to claim 3, characterized in that, The first heating resistor and the second heating resistor cover one side of the main body structure; or, The first heating resistor and the second heating resistor cover a portion of the area on one side of the atomic gas chamber.

5. The atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetoencephalography (MEG) device according to claim 1, characterized in that, The encapsulation structure further includes a support assembly, which is placed in the vacuum-sealed cavity, and the atomic gas chamber is placed on the support assembly; The support assembly includes a first support assembly and a second support assembly, the second support assembly being located on one side of the first support assembly, and the atomic gas chamber being disposed on the side of the second support assembly away from the first support assembly; The first support component is a hollow structure, the atomic gas chamber corresponds to the hollow region of the first support component, and the hollow region of the first support component is connected to the vacuum sealing cavity.

6. The atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetoencephalography (MEG) device according to claim 5, characterized in that, The second support assembly includes a first line support assembly arranged along a first direction, wherein the atomic gas chamber is disposed on the side of the first line support assembly away from the first support assembly, and along a direction perpendicular to the plane of the support assembly, the projected width of the first line support assembly is smaller than the projected width of the atomic gas chamber; and / or, The second support component includes a second line support component arranged along a second direction. The atomic gas chamber is disposed on the side of the first line support component and the second line support component away from the first support component. Along a direction perpendicular to the plane where the support component is located, the projected width of the second line support component is smaller than the projected width of the atomic gas chamber. Wherein, the first direction is parallel to the plane where the support component is located, and the projected width of the first line support component and the projected width of the atomic gas chamber are the widths along the first direction; the second direction is parallel to the plane where the support component is located, and the second direction intersects the first direction, and the projected width of the second line support component and the projected width of the atomic gas chamber are the widths along the first direction.

7. The atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetoencephalography (MEG) device according to claim 5, characterized in that, The second support assembly includes a thin film support assembly, and the atomic gas chamber is disposed on the side of the thin film support assembly away from the first support assembly; Along a direction perpendicular to the plane where the support component is located, the projection of the atomic gas cell is located in the projection of the thin film support component, and the thickness of the thin film support component is not greater than a second preset value.

8. The atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetoencephalography (MEG) device according to claim 7, characterized in that, The second preset value is no greater than 50 μm.

9. The atomic gas cell encapsulation structure for realizing a high-density optically pumped magnetoencephalography (MEG) device according to claim 1, characterized in that, The encapsulation structure further includes a heat radiation reflective layer, which is disposed on the inner side of the main structure; The main structure includes multiple sides that surround the vacuum-sealed cavity, and the thermal radiation reflective layer is disposed on the inner side of at least one of the multiple sides, and the thermal radiation reflective layer covers a portion of the area of ​​the side on which it is located; wherein, the polarized beam of the atomic gas chamber is transmitted to the atomic gas chamber through the area not covered by the thermal radiation reflective layer.

10. A light-pumped magnetometer for realizing high-density integrated magnetoencephalography (MEG) equipment, characterized in that, include: Atomic gas cell encapsulation structure, laser source, circular polarizer, reflector and photoelectric converter; The laser source emits a laser beam, which is transmitted sequentially through the circular polarizer and the mirror to the atomic gas cell encapsulation structure to generate a detection beam. The photoelectric converter generates a detection signal based on the detection beam, and the detection signal is used to realize magnetoencephalography (MEG) imaging. The atomic gas chamber encapsulation structure is the atomic gas chamber encapsulation structure according to any one of claims 1-9.

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