阅读说明：本技术 一种中性原子二维成像装置及成像方法 (Neutral atom two-dimensional imaging device and imaging method ) 是由 宗秋刚 王永福 王玲华 邹鸿 叶雨光 陈鸿飞 于向前 施伟红 周率 于 2020-12-18 设计创作，主要内容包括：本发明提供一种中性原子二维成像装置及成像方法,该成像装置包括具有成像平面的卫星平台及成像模块单元,成像模块单元沿不同的方向布置在成像平面内,例如沿成像平面的中心呈放射状分布。成像模块单元包括至少一个半导体探测器线阵列,及至少一个设置在至少一个半导体探测器线阵列前方的调制栅格。在成像平面内,成像模块单元的调制栅格一侧沿成像平面的法线方向朝向待测空间。每一个成像模块单元对应一个方向,每一个成像模块单元覆盖45°×10°的视场范围,多个成像模块单元实现45°×45°视场内的二维成像。卫星平台可以是三轴稳定或自旋稳定的卫星平台,不同的卫星平台内设置不同的成像模块单元的分布,通过不同的方式实现中性原子的二维成像。(The invention provides a neutral atom two-dimensional imaging device and an imaging method. The imaging module unit includes at least one array of semiconductor detector lines and at least one modulation grid disposed in front of the at least one array of semiconductor detector lines. In the imaging plane, one side of the modulation grid of the imaging module unit faces the space to be measured along the normal direction of the imaging plane. Each imaging module unit corresponds to one direction, each imaging module unit covers a field of view range of 45 degrees multiplied by 10 degrees, and the plurality of imaging module units realize two-dimensional imaging in the field of view of 45 degrees multiplied by 45 degrees. The satellite platform can be a satellite platform with stable three-axis or stable self-rotation, different imaging module units are arranged in different satellite platforms and distributed, and two-dimensional imaging of neutral atoms is realized in different modes.)

1. A neutral atom two-dimensional imaging apparatus, comprising:

a satellite platform having an imaging plane;

an imaging module unit disposed within the imaging plane and distributed in different directions of the imaging plane, wherein the imaging module unit includes:

at least one semiconductor detector line array, each of the semiconductor detector line arrays comprising a semiconductor detector strip comprised of a plurality of semiconductor detectors; and

the modulation grid is arranged in front of the at least one semiconductor detector line array, has a distance D with the semiconductor detector line array, and is in one-to-one correspondence with the at least one semiconductor detector line array, the modulation grid performs spatial Fourier transform on incident neutral atoms, and in the imaging plane, one side of the modulation grid of the imaging module unit faces to a space to be measured along the normal direction of the imaging plane.

2. A neutral atom two-dimensional imaging apparatus according to claim 1, wherein the satellite platform is a three-axis stabilized platform.

3. A neutral atom two-dimensional imaging device according to claim 2, wherein the imaging plane is divided into n equal angles on average in the range of 0-180 ° along the center of the imaging plane, each angle corresponds to one direction, and one imaging module unit is placed in each direction, wherein n is a natural number greater than 1.

4. A neutral atom two-dimensional imaging apparatus according to claim 3, wherein a center angle of a field angle of an i-th imaging module unit in the imaging plane isWhere i is 1, … …, n.

5. The neutral atomic two-dimensional imaging device according to claim 1, wherein the satellite platform is a spin stabilization platform that stabilizes spins around a spin axis, and the spin period of the satellite platform is T.

6. A neutral atom two-dimensional imaging device according to claim 5, wherein the imaging plane is divided into m equal angles on average in the range of 0-180 ° along the center of the imaging plane, each angle corresponds to one direction, and one imaging module unit is placed in each direction, wherein m is a natural number greater than 1.

7. The neutral atom two-dimensional imaging device of claim 6, wherein 1/2 of the spin cycle of the satellite platform is averaged to k, and the central angle of the field of view angle of the i-th imaging module unit in the imaging plane is k in the j-th time periodWherein i is 1, … …, m, j is 1, … …, k, k is a natural number greater than 1.

8. A neutral atom two-dimensional imaging apparatus according to claim 1, wherein a field angle of the imaging module unit is 10 °.

9. A neutral atom two-dimensional imaging device according to claim 1, wherein the modulation grid comprises slits and solid bars of the grid forming the slits, the extension direction of the semiconductor detector bars coincides with the extension direction of the slits of the modulation grid, the modulation grid comprises a plurality of grid periods, each grid period comprises z slits, the width of the semiconductor detector bar is d, the width w of the y-th slit of the modulation grid is_yThe following relationship is satisfied:

10. a neutral atom two-dimensional imaging device according to claim 1, wherein the imaging module unit further comprises a collimation deflection module disposed in front of the modulation grid, the collimation deflection module comprising a collimator and a deflection plate.

11. The neutral atom two-dimensional imaging device according to claim 1, further comprising a preamplifier unit and a main control and interface unit, wherein the imaging module unit, the preamplifier and the main control and interface unit are electrically connected; the pre-amplifier unit reads the imaging data of the imaging module unit and amplifies the imaging data.

12. The neutral atom imager of claim 8, further comprising a data processing unit for receiving the imaging signal transmitted by the preamplifier, and processing, packaging, and compressing the imaging signal.

13. A neutral atom two-dimensional imaging device according to any one of claims 1 to 12, wherein the imaging module units are radially distributed along the center of the imaging plane in the imaging plane.

14. A neutral atom imaging method, comprising the steps of:

arranging imaging module units in an imaging plane, wherein the imaging module units are distributed in different directions of the imaging plane;

receiving, by the imaging module unit, neutral atoms in different directions;

spatially Fourier transforming the neutral atoms by a modulation grid in the imaging module unit;

detecting the neutral atoms subjected to space Fourier transform by a semiconductor detector line array in the imaging module unit, and generating an imaging signal in the direction of the imaging module unit;

and synthesizing imaging signals of each imaging module unit in the corresponding direction to obtain a two-dimensional imaging signal of the neutral atom.

15. The method of claim 14, wherein receiving neutral atoms in different directions by the imaging module unit further comprises the steps of:

deflecting the incoming charged particles such that they do not reach the array of semiconductor detector lines of the imaging module unit.

16. A neutral atom imaging method as claimed in claim 14, further comprising the steps of:

amplifying the imaging signal;

processing, packing and compressing the amplified imaging signal.

17. A neutral atom imaging method as claimed in claim 16, wherein the step of amplifying the imaging signal further comprises the steps of:

providing operational timing to at least one of said preamplifier units;

acquiring and reading the imaging signals according to the operation time sequence;

and carrying out preliminary fusion and processing on the acquired and read imaging signals.

18. A neutral atom imaging method as claimed in claim 17, wherein the acquiring and reading the imaging signals according to the operation timing further comprises the steps of:

shaping the imaging signal and converting the imaging signal into an analog signal;

the peak of the analog signal is detected and held until the peak is read.

19. A neutral atom imaging method according to any one of claims 14 to 18, wherein arranging the imaging module unit in the imaging plane includes: the imaging module units are radially arranged along the center of the imaging plane.

Technical Field

The application relates to the field of neutral atom imaging, in particular to a neutral atom two-dimensional imaging device and an imaging method.

Background

Global observation and global imaging have become one of the important avenues of development with a hope of solving geospatial physics problems. Energy Neutral Atoms (ENA) are generated during the charge exchange process between the ring current ions and the corona hot particle component, and the ENA is not bound by the magnetic field and can leave the source region along a straight line at the speed of the original energy ions. Telemetry ENA imaging also provides new opportunities to distinguish temporal and spatial variations of spatial plasma.

Neutral atoms are distributed in the earth space in a spatial mode, so that the neutral atoms need to be imaged in an all-around mode in order to guarantee imaging accuracy. Based on the method, the invention provides a neutral atom two-dimensional imaging device and an imaging method.

Disclosure of Invention

In order to solve the problem of ENA two-dimensional imaging, the invention provides a neutral atom two-dimensional imaging device and an imaging method. Each imaging module unit covers a field of view (FOV) range of 45 ° × 10 °, and the plurality of imaging module units realize two-dimensional imaging within the FOV of 45 ° × 45 °, and finally obtain two-dimensional distribution of neutral atoms in the detection space. In addition, different satellite platforms, such as a three-axis stable satellite platform and a spin stable satellite platform, can be selected, so that different imaging module units can be distributed, and two-dimensional imaging of neutral atoms can be realized in different modes.

According to a first aspect of the present invention, there is provided a neutral atom two-dimensional imaging apparatus comprising:

a satellite platform having an imaging plane;

an imaging module unit disposed within the imaging plane and distributed in different directions of the imaging plane, wherein the imaging module unit includes:

at least one semiconductor detector line array, each of the semiconductor detector line arrays comprising a semiconductor detector strip comprised of a plurality of semiconductor detectors; and

the modulation grid is arranged in front of the at least one semiconductor detector line array, has a distance D with the semiconductor detector line array, and is in one-to-one correspondence with the at least one semiconductor detector line array, the modulation grid performs spatial Fourier transform on incident neutral atoms, and in the imaging plane, one side of the modulation grid of the imaging module unit faces to a space to be measured along the normal direction of the imaging plane.

Optionally, the satellite platform is a three-axis stabilized platform.

Optionally, the imaging plane is equally divided into n parts with the same angle along the center of the imaging plane within the range of 0-180 °, each angle corresponds to one direction, and one imaging module unit is placed in each direction, where n is a natural number greater than 1.

Optionally, in the imaging plane, the center angle of the field angle of the i-th imaging module unit is Where i is 1, … …, n.

Optionally, the satellite platform is a spin stabilization platform that stabilizes spin around a spin axis, and a spin period of the satellite platform is T.

Optionally, the imaging plane is divided into m equal angles on average in the range of 0 to 180 ° along the center of the imaging plane, each angle corresponds to one direction, and one imaging module unit is placed in each direction, where m is a natural number greater than 1.

Optionally, 1/2 of the spin cycle of the satellite platform is averaged to k, and in the j time period, the central angle of the field of view angle of the i-th imaging module unit in the imaging plane is the j time periodWherein i is 1, … …, m, j is 1, k is a natural number larger than 1.

Optionally, the imaging module unit has a field angle of 10 °.

Optionally, the modulation grid includes slits and grid solid bars forming the slits, an extending direction of the semiconductor detector strip is consistent with an extending direction of the slits of the modulation grid, the modulation grid includes a plurality of grid periods, each grid period includes z slits, a width of the semiconductor detector strip is d, and a width w of a y-th slit of the modulation grid is_yThe following relationship is satisfied:

optionally, the imaging module unit further comprises a collimation deflection module disposed in front of the modulation grid, the collimation deflection module comprising a collimator and a deflection plate.

Optionally, the neutral atom two-dimensional imaging device further comprises a preamplifier unit and a main control and interface unit, wherein the imaging module unit, the preamplifier and the main control and interface unit are electrically connected; the pre-amplifier unit reads the imaging data of the imaging module unit and amplifies the imaging data.

Optionally, the neutral atom two-dimensional imaging device further includes a data processing unit, configured to receive the imaging signal transmitted by the preamplifier, and process, pack, and compress the imaging signal.

Optionally, the imaging module units are radially distributed along the center of the imaging plane in the imaging plane.

In a second aspect of the present invention, there is provided a neutral atom imaging method comprising the steps of:

arranging imaging module units in an imaging plane, wherein the imaging module units are distributed in different directions of the imaging plane;

receiving, by the imaging module unit, neutral atoms in different directions;

spatially Fourier transforming the neutral atoms by a modulation grid in the imaging module unit;

detecting the neutral atoms subjected to space Fourier transform by a semiconductor detector line array in the imaging module unit, and generating an imaging signal in the direction of the imaging module unit;

and synthesizing imaging signals of each imaging module unit in the corresponding direction to obtain a two-dimensional imaging signal of the neutral atom.

Optionally, the receiving, by the imaging module unit, neutral atoms in different directions further comprises the steps of: deflecting the incoming charged particles such that they do not reach the array of semiconductor detector lines of the imaging module unit. .

Optionally, the method further comprises the steps of:

amplifying the imaging signal;

processing, packing and compressing the amplified imaging signal.

Optionally, the step of amplifying the imaging signal further comprises the steps of:

providing operational timing to at least one of said preamplifier units;

acquiring and reading the imaging signals according to the operation time sequence;

and carrying out preliminary fusion and processing on the acquired and read imaging signals.

Optionally, the acquiring and reading the imaging signal according to the operation timing sequence further includes:

shaping the imaging signal and converting the imaging signal into an analog signal;

the peak of the analog signal is detected and held until the peak is read.

Optionally, arranging the imaging module unit within the imaging plane comprises: the imaging module units are radially arranged along the center of the imaging plane.

As described above, the neutral atom two-dimensional imaging apparatus and the imaging method according to the present invention have at least the following advantageous effects:

the invention selects a proper imaging plane on the satellite platform, and arranges the imaging module units in different directions in the imaging plane, for example, the imaging module units are uniformly arranged in a radial shape along the center of the imaging plane, and each imaging module unit corresponds to one direction. Each imaging module unit covers a field of view (FOV) range of 45 ° × 10 °, and the plurality of imaging module units realize two-dimensional imaging within the FOV of 45 ° × 45 °, and finally obtain two-dimensional distribution of neutral atoms in the detection space. In addition, different satellite platforms, such as a three-axis stable satellite platform and a spin stable satellite platform, can be selected, so that different imaging module units can be distributed, and two-dimensional imaging of neutral atoms can be realized in different modes.

Drawings

The features and advantages of the present invention will be more clearly understood by reference to the accompanying drawings, which are illustrative and not to be construed as limiting the invention in any way, and in which:

fig. 1 is a schematic diagram of a neutral atom two-dimensional imaging apparatus according to an embodiment of the present invention.

Fig. 2a is a schematic diagram illustrating the angular division of the imaging plane shown in fig. 1 in an alternative implementation of this embodiment.

Fig. 2b shows a schematic view of the distribution of the imaging module units in the imaging plane shown in fig. 2 a.

Fig. 2c shows a schematic view of the angular division of the imaging plane shown in fig. 1 in an alternative embodiment to the first embodiment.

Fig. 2d shows a schematic view of the distribution of the imaging module units in the imaging plane shown in fig. 2 c.

Fig. 3 shows a schematic diagram of a modulation grid and an array of semiconductor detector lines in an imaging module unit.

Fig. 4 is a schematic diagram of the structure of the modulation grid in fig. 3.

Fig. 5 is a schematic structural diagram of the array of semiconductor detector lines of fig. 3.

Fig. 6 shows a schematic view of an imaging module unit.

FIG. 7 is a schematic flow chart of a neutral atom imaging method of the present invention.

Fig. 8 is a schematic view of a neutral atom two-dimensional imaging device according to a second embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example one

The present embodiment provides a neutral atom two-dimensional imaging device, and in the present embodiment, the neutral atom two-dimensional imaging device includes a satellite platform and an imaging module unit disposed on the satellite platform.

In this embodiment, the satellite platform is a three-axis stable platform, that is, the satellite platform does not rotate with time, and the direction of the imaging module unit on the satellite platform is unchanged in each time period. Fig. 1 shows a three-axis stabilized satellite platform and imaging module units distributed in the imaging plane of the satellite platform.

As shown in FIG. 1, the satellite platform 100 is illustrated as a satellite trussThe gantry, within the satellite truss, selects an imaging plane 101, which imaging plane 101 may be selected based on the orbit of the satellite and the area 200 for which the observation is planned. The imaging module units 300 are distributed in different directions of the imaging plane 101. Specifically, in an imaging plane, the imaging plane is equally divided into n parts along the center O of the imaging plane within the range of 0-180 degrees, each part corresponds to an angle, namely, a direction, wherein n is a natural number greater than 1. One imaging module unit is placed in each direction such that the imaging module units are radially arranged along the center O in the imaging plane. In the imaging plane, the central angle phi of the view field direction of the ith imaging module unit is as follows: where i is 1, … …, n. The n imaging module units form a complete neutral atom imager, and two-dimensional imaging in a 45-degree and 45-degree field of view is realized.

In an alternative embodiment of this embodiment, n is 10 as an example. As shown in fig. 2a, the imaging plane is divided into 10 equal parts in the range of 0 to 180 °, each part corresponds to one direction, i.e., the imaging plane is divided into 10 directions, and in fig. 2a, one diameter corresponding to parts 1,2, … …, and 10 is one direction. One imaging module unit 300 is placed in each direction, i.e., the central angle of the field of view direction of the imaging module unit corresponds to each direction of the above-described equipartition. Therefore, on the premise of ensuring that the central angle of the view field of the imaging module unit corresponds to each direction, the imaging module unit can translate in the imaging plane and is positioned at any position of the imaging plane. The placement position of the imaging module unit can be adjusted according to factors such as the size of an imaging platform in the imaging device. In the imaging plane, the central angle Φ of the view field direction of the i-th imaging module unit 300 corresponds to: where i is 1, … …, 10.

Fig. 2b shows the distribution of the imaging module unit 300 therein. Wherein a part (e.g. 5) of the imaging module units are radially distributed in the imaging plane along different angular centers of the imaging plane, and another part (another 5) of the imaging module units are radially distributed in the imaging plane along different angles of the imaging plane. The arrangement mode can ensure that the imaging module units are distributed in 10 different directions in the imaging plane, and the positions of the imaging module units can be changed at will under the condition that the corresponding directions are not changed. The above-described imaging module unit may be arranged in a manner that occupies as small an area as possible, for example, in consideration of the size of the imaging apparatus.

In another alternative embodiment of this embodiment, taking n-11 as an example, as shown in fig. 2c, the imaging plane is equally divided into 11 parts in the range of 0 to 180 °, each part corresponds to one direction, that is, the imaging plane is divided into 11 directions, and in fig. 2c, one diameter corresponding to parts 1,2, … …, and 11 is one direction. One imaging module unit 300 is placed in each direction, i.e., the central angle of the field of view direction of the imaging module unit corresponds to each direction of the above-described equipartition. Therefore, on the premise of ensuring that the central angle of the view field of the imaging module unit corresponds to each direction, the imaging module unit can translate in the imaging plane and is positioned at any position of the imaging plane. The placement position of the imaging module unit can be adjusted according to factors such as the size of an imaging platform in the imaging device. In the imaging plane, the central angle Φ of the view field direction of the i-th imaging module unit 300 corresponds to: where i is 1, … …, 11.

Fig. 2d shows the distribution of the imaging module unit 300 therein. Wherein, 11 image module units are radially distributed along different angle centers of the imaging plane in the imaging plane. This arrangement ensures that the imaging module units are distributed in 11 different directions in the imaging plane. It should be understood that the position of the imaging module unit can likewise be changed at will without the corresponding direction being changed.

As shown in fig. 3, a modulation grid 301 and an array of detector lines 302 in an imaging module unit 300 are shown. Each imaging module unit comprises at least one semiconductor detector line array and at least one modulation grid, and each semiconductor detector line array comprises a semiconductor detector strip consisting of a plurality of semiconductor detectors; at least one modulation grid is arranged in front of at least one of the semiconductor detector line arrays with a spacing D and in one-to-one correspondence with at least one of the semiconductor detector line arrays, the modulation grid performing a spatial fourier transform of incident neutral atoms.

As shown in fig. 1, the imaging plane 101 is directed towards the observation space 200, and the modulation grid 301 in the imaging module unit 300 in the imaging plane is directed towards the observation space 200.

As shown in fig. 4, a schematic diagram of the structure of the modulation grid 301 shown in fig. 3 is given. In this embodiment, the modulation grid 301 is a single layer modulation multiple slit grid. As shown in fig. 4, the modulation grid 301 includes slits 3011 and grid solid bars 3012 forming the slits, each slit 3011 has the same width as the grid solid bar 3012 forming the slit 30111, and one slit 3011 and one solid bar 3012 constitute one pitch. It should be understood that each slit is defined by two solid bars of the grid on the left and right in the arrangement direction of the slits 101 shown in fig. 2, and herein, the solid bar of the grid 102 on the right side of the slit 101 is defined as the solid bar of the grid forming the slit.

Referring to fig. 5, a schematic structural diagram of the semiconductor detector line array 302 of fig. 3 is shown. As shown in fig. 5, the semiconductor detector line array 302 is arranged on its carrier plate 303, and the size of the carrier plate of the semiconductor detector line array is 150mm × 45mm to 180mm × 60 mm. In a more preferred embodiment of this embodiment, the distance D between the array of semiconductor detector lines and the modulation grid is between 10mm and 15 mm. A semiconductor detector line array 302 includes a plurality of semiconductor detector strips 3021, each semiconductor detector strip 3021 including a plurality of linearly arranged semiconductor detectors. Referring again to fig. 3, the direction of extension of the semiconductor detector strips in the array of semiconductor detector lines coincides with the direction of extension of the slits 3011 of the modulation grid 301. Preferably, the length of the array of semiconductor detector lines corresponds to the length of the modulation grid.

In an alternative embodiment, the width of the semiconductor detector strip 3021 is defined as d. The width of the semiconductor detector strip varies depending on the type of semiconductor detector.

In an alternative embodiment of this embodiment, the semiconductor detectors in the semiconductor detector strip 3021 include a thin window, very low energy threshold semiconductor detector (SSD) with a threshold of about 2keV, with a surface of a sensitive region of the semiconductor detector being plated with a polysilicon layer and an aluminum layer over the polysilicon layer. The width d of the semiconductor detector strips formed by the semiconductor detector is about 0.45mm, while the gap between the semiconductor detector strips is small, only 0.05 mm. In a more preferred embodiment of this embodiment, the polysilicon has a thickness betweenThe thickness of the aluminum layer is between In the most preferred embodiment of this embodiment, the semiconductor detector comprises a polysilicon layer having a thickness ofThe thickness of the aluminum layer isIs/are as followsSemiconductor detector with window thickness and polysilicon layer with thickness ofThe thickness of the aluminum layer isIs/are as followsA semiconductor detector of window thickness. In the preferred embodiment, the semiconductor detector is capable of detecting particles including neutral hydrogen atoms (H) and oxygen atoms (O), the energy range of the detected H being from 2keV to 200keV, and the energy range of the detected O being from 8keV to 250 keV.

Referring again to fig. 4, in the present embodiment, one modulation grid 10 includes a plurality of grid periods, each including a plurality of slits. The width of the slits varies regularly during one grid period. The modulation grid 301 comprises x grid periods, and z slits are defined in one grid period, the widest slit is the 1 st slit, and the width of the y-th slit is w_yThe width of the y-th slit is w_yThe width d of the semiconductor detector line array satisfies the following relation:in a preferred embodiment, the width of the narrowest slit (i.e. the z-th slit) in a defined grid period is the same as the width d of the semiconductor detector strip, i.e. w_iD. In alternative embodiments, x ≧ 2, z ≧ 8. The width of each slit in one grid period and the width of the grid solid bar forming the slit can be determined according to the slit width formula, and then the required modulation grid is formed according to the number of the grid periods in the modulation grid. According to the principle of neutral atom imaging, the thickness of the modulation grid is preferably as small as possible, and the ideal thickness is 0, whereas in the present embodiment, in order to obtain a modulation grid as thin as possible, the thickness of the modulation grid is defined as s, and the following conditions are satisfied:in a more preferred embodiment, the thickness of the modulation grid is approximately 0.1 mm.

As described above, having determined the width of the semiconductor detector strip (i.e., the width of the narrowest slit in the modulation grid), D, and the distance between the modulation grid and the array of semiconductor detector lines, D, the angular resolution of the neutral atom imaging unit can be determined as:

still referring to FIG. 4, in a preferred embodiment, the outer length L of the modulation grid 301₁120 mm-130 mm, inner side length L₂Between 110mm and 120mm, and an outer width H₁30 mm-50 mm, inner width H₂Is between 20mm and 30 mm. That is, the size of the multi-slit grid is 120mm × 30mm to 130mm × 50 mm. The thickness of the multiple slit grid may be 0.1mm or 0.2 mm.

Neutral atoms from the same incident direction (i.e. same velocity) are spatially fourier transformed by a modulating multi-slit grid of varying slit width, which transforms the incident neutral atoms so that the count rate of neutral atoms received by the detector line array varies with the position of the detector. By utilizing the characteristics of the neutral atom imaging unit and performing Fourier inversion on neutral atoms detected by the semiconductor detector line array, the spatial distribution of the neutral atoms in different directions can be obtained, and thus the position and the size of the source region can be obtained. In this embodiment, since a plurality of imaging module units are disposed in different directions in the imaging plane, and each imaging module unit performs the above detection on the neutral atom, the neutral atom detection system of this embodiment can realize two-dimensional imaging of the neutral atom, and inverted neutral atom distribution into the observation space.

In another preferred embodiment of this embodiment, the neutral atom imaging module unit further includes a collimation deflection module, and the collimation deflection module includes a collimator and a deflection plate. The collimation deflection module comprises a collimator and a deflection plate, and charged particles such as various electrons and ions are deflected by applying a deflection voltage to the deflection plate, so that the grid imaging unit only detects the neutral atoms and images the neutral atoms.

As shown in fig. 6, a schematic view of the neutral atom imaging unit is shown. In fig. 6, the imaging field angle in the neutral atom imaging unit is 45 °, and for convenience of illustration, the modulation grid 301 and the semiconductor detector line array 302 of the neutral atom imaging unit are shown in the XY direction, and actually, in the imaging process, the modulation grid and the semiconductor detector line array of the neutral atom imaging unit are placed along the YZ plane shown in fig. 6, with an imaging field angle of 45 °, and the neutral atom imaging unit performs detection imaging of neutral atoms within a 45 ° field angle of the XZ plane, that is, a view of a portion of a circle a in fig. 6 is actually a view rotated by 90 ° along a normal direction of the YZ plane. The field angle of the neutral atom imaging unit in the XY plane is 10 °. In the preferred embodiment, the length of the deflection plate 313 is 190mm, the distance between the two deflection plates is 30mm, the distance between the deflection plate 313 and the modulation grid 10 is 30mm, a voltage of 6kV is applied to the deflection plate 313, the particles entering the deflection plate 313 generally include neutral atoms and various charged particles, and after entering the deflection plate 313 charged with the above-mentioned voltage, the deflection plate 313 deflects the various charged particles by the voltage. In this embodiment, the deflection plate is capable of deflecting a majority of the charged particles of 30keV such that only neutral atoms enter the neutral atom imaging unit, are spatially fourier transformed by the modulation grid of the neutral atom imaging unit, and are detected and imaged by the semiconductor detector.

The two-dimensional imaging apparatus of the present embodiment can image in different directions at the same time by n imaging module units arranged in different directions within the imaging plane, and two-dimensional imaging within a field of view of 45 ° × 45 ° is realized in different directions within the imaging plane.

In an optional embodiment, the neutral atom two-dimensional imaging apparatus further includes a signal processing system for processing an imaging signal of the imaging module unit, the signal processing system includes at least one preamplifier unit and at least one master control and interface unit, and the neutral atom imaging module unit, the at least one preamplifier unit and the at least one master control and interface unit are electrically connected to each other.

The preamplifier unit reads the imaging data of at least one neutral atom imaging module unit and performs preliminary amplification on the imaging data. The preamplifier unit comprises a plurality of application-specific integrated circuits, and the application-specific integrated circuits read the imaging signals of at least one neutral atom imaging unit in real time and amplify the imaging signals.

The preamplifier unit comprises at least one charge sensitive preamplifier, at least one multi-stage shaper and at least one peak detector, which detects and holds a peak of the imaging signal until the peak is read out.

The main control and interface unit provides operation time sequence for the at least one special integrated circuit, controls the at least one special integrated circuit to complete the acquisition and reading of imaging signals, and performs preliminary fusion and processing on the imaging signals.

The signal processing system also comprises a data processing unit, wherein the data processing unit receives the imaging signal transmitted by the preamplifier in the neutral atom imager, and processes, packs and compresses and stores the imaging signal. In a preferred embodiment of this embodiment, the neutral atomic imaging module unit is communicatively connected to the data processing unit by using the main control and interface unit as an interface.

The present embodiment also provides a neutral atom imaging method that performs imaging by the above-described neutral atom imaging system of the present embodiment. As shown in fig. 7, the method includes the steps of:

s101: arranging imaging module units in an imaging plane, wherein the imaging module units are distributed in different directions of the imaging plane;

s102: receiving, by the imaging module unit, neutral atoms in different directions;

in an alternative embodiment, neutral atoms of different directions are received by the imaging module unit, and charged particles mixed in the incident neutral atoms are first deflected, so that only the neutral atoms are detected and the charged particles do not reach the array of semiconductor detector lines of the imaging module unit.

S103: spatially Fourier transforming the neutral atoms by a modulation grid in the imaging module unit;

s104: detecting the neutral atoms subjected to space Fourier transform by a semiconductor detector line array in the imaging module unit, and generating an imaging signal in the direction of the imaging module unit;

s105: and synthesizing imaging signals of each imaging module unit in the corresponding direction to obtain a two-dimensional imaging signal of the neutral atom.

In a preferred embodiment of this embodiment, the method further includes the steps of:

amplifying the imaging signal;

processing, packing and compressing the amplified imaging signal.

In another preferred embodiment of this embodiment, the step of amplifying the imaging signal further comprises the steps of:

providing operational timing to at least one of said preamplifier units;

acquiring and reading the imaging signals according to the operation time sequence;

and carrying out preliminary fusion and processing on the acquired and read imaging signals.

In another preferred embodiment of this embodiment, the acquiring and reading the imaging signal according to the operation timing further includes:

performing signal shaping on the imaging signal, and converting the imaging signal into an analog signal;

the peak of the analog signal is detected and held until the peak is read.

Example two

The embodiment also provides a neutral atom two-dimensional imaging device which also comprises a satellite platform and an imaging module unit arranged on the satellite platform. The imaging module unit is the same as that of the first embodiment, and will not be described in detail. The neutral atom two-dimensional imaging device of the present embodiment is different from the neutral atom two-dimensional imaging device of the first embodiment in that:

as shown in fig. 8, the satellite platform 100 in this embodiment is a spin-stabilized platform, and the satellite platform 100 stably rotates around a spin axis P in a counterclockwise direction or a clockwise direction. In the present embodiment, as shown in fig. 8, the satellite platform 100 spins in the counterclockwise direction (indicated by arrow R in fig. 8) about the spin axis P.

For the spin-stabilized satellite platform 100 shown in fig. 8, an imaging plane 101 is also selected, which is a plane perpendicular to the spin axis P of the satellite platform, and the imaging plane 101 can also be selected according to the orbit of the satellite and the planned observation area 200.

Assuming that the spin period of the satellite platform 100 is T (seconds), the plane perpendicular to the spin axes may be rotated by 180 degrees in T/2 of the time. The center O of the imaging plane is taken as the center, the imaging plane is equally divided into m parts within the range of 0-180 degrees, and each part corresponds to an angle, namely a direction. Placing one imaging module unit in each direction; meanwhile, equally dividing the time of T/2 into k parts; a j-th time period in which a center angle of a field angle of an i-th imaging module unit in the imaging plane is Wherein i is 1, … …, m, j is 1, k is a natural number larger than 1. Wherein, the time corresponding to the jth time periodWhere j is 1,2, … …, k.

The distribution of the imaging module units in the imaging plane is the same as the arrangement shown in the first embodiment, and reference is made to the first embodiment and fig. 2b and 2d, which will not be described in detail here.

Due to the advantage of the self-rotation of the satellite platform, the neutral atom detection is carried out on the same space, and the number m of imaging module units arranged in the self-rotation stable satellite platform is less than the number n of imaging module units arranged on the three-axis stable platform. However, to realize the detection in the same direction, the self-rotation of the spin-stabilized satellite platform is needed to be completed, so the imaging time of the spin-stabilized satellite platform is slightly longer than that of the three-axis stabilized undetermined platform. The distribution of the imaging module elements in the imaging plane is similar to that shown in fig. 2, with only a quantitative difference.

For the imaging range realized by setting 10 imaging module units in the first embodiment, on the optional stable satellite platform of the first embodiment, the imaging plane is equally divided into 5 parts within the range of 0-180 degrees, that is, m is 5; and dividing T/2 equally into 2, namely, k is 2, so that the effect that the triaxial stable platform n is 10 can be realized. Each imaging module unit corresponds to different directions at different moments, so that the neutral atom detection in two-dimensional space can be completed in the spin period T of the satellite platform.

The processing of the detection data of the subsequent imaging module unit is the same as the method of the first embodiment, and is not described herein again.

In summary, the neutral atom two-dimensional imaging apparatus and the neutral atom imaging method provided by the embodiments of the invention at least have the following technical effects:

the invention selects a proper imaging plane on the satellite platform, and arranges the imaging module units in different directions in the imaging plane, for example, the imaging module units are uniformly arranged in a radial shape along the center of the imaging plane, and each imaging module unit corresponds to one direction. Each imaging module unit covers a field of view (FOV) range of 45 ° × 10 °, and the plurality of imaging module units realize two-dimensional imaging within the FOV of 45 ° × 45 °, and finally obtain two-dimensional distribution of neutral atoms in the detection space. In addition, different satellite platforms, such as a three-axis stable satellite platform and a spin stable satellite platform, can be selected, so that different imaging module units can be distributed, and two-dimensional imaging of neutral atoms can be realized in different modes.

The foregoing embodiments are merely illustrative of the principles of this invention and its efficacy, rather than limiting it, and various modifications and variations can be made by those skilled in the art without departing from the spirit and scope of the invention, which is defined in the appended claims.