Imaging method using multiple radiation beams

Abstract

Disclosed herein is a method comprising: transmitting a set of radiation beams (i,j), i=1,..., M and j=1,..., Ni, to a same scene, wherein each set of radiation beams comprises a plurality of parallel fan-shaped radiation beams transmitted simultaneously, wherein for each value of i, the sets of radiation beams (i,j), j=1,..., Ni, are parallel to each other and one set is transmitted at a time, and wherein no two radiation particle paths in any two respective sets of radiation beams having different values of i are parallel to each other; capturing a local image (i,j) of the scene with radiation of the set of radiation beams (i,j) for i=1,..., M and j=1,..., Ni; stitching the local images (i,j), j=1,..., Ni, for each value of i; and reconstructing a 3-dimensional image of the scene from the stitched images (i), i=1,..., M.

Description

[Background Technology]

[0001] A radiation detector is a device for measuring the properties of radiation. Examples of properties can include the spatial distribution of the intensity, phase, and polarization of the radiation. The radiation can be radiation that has already interacted with an object. For example, the radiation measured by a radiation detector can be radiation that has already penetrated an object. The radiation can be electromagnetic radiation, such as infrared light, visible light, ultraviolet light, X-rays, or gamma rays. The radiation can also be other types, such as alpha rays and beta rays. Imaging systems can include image sensors with multiple radiation detectors. [Summary of the Invention]

[0002] This document discloses a method comprising: transmitting radiation beam groups (i,j), i = 1, ..., M and j = 1, ..., Ni, to the same scene, wherein M and Ni, i = 1, ..., M are integers greater than 1, wherein each of the radiation beam groups (i,j), i = 1, ..., M and j = 1, ..., Ni comprises a plurality of parallel fan-shaped radiation beams transmitted simultaneously, wherein for each value of i, the fan-shaped radiation beams of the radiation beam groups (i,j), j = 1, ..., Ni are parallel to each other, wherein for each value of i, the radiation beam groups (i,j), j = 1, ..., Ni are transmitted one group at a time, and wherein for any of 1, ..., M, ... For the same i1 and i2, the radiation particle paths of any two corresponding radiation beam groups (i1,j), i=1, ..., Ni1 and radiation beam group (i2,j), j=1, ..., Ni2 in the radiation beam groups (i,j), i=1, ..., M and j=1, ..., Ni are not parallel to each other; for i=1, ..., M and j=1, ..., Ni, a local image (i,j) of the scene is captured by the radiation of the radiation beam group (i,j); for each value of i, the local image (i,j), j=1, ..., Ni is stitched together to obtain a stitched image (i) of the scene; and a 3D image of the scene is reconstructed from the stitched image (i), i=1, ..., M.

[0003] On one hand, for each value of i, sending the radiation beam group (i, j), j = 1, ..., Ni to the same scene includes: (A) between the same radiation source and the scene and (B) translating the same collimator in the normal direction (i) perpendicular to the radiation beam group (i, j), j = 1, ..., Ni.

[0004] In one aspect, the collimator includes a plurality of parallel slits configured to allow radiation from the radiation source incident on and parallel to the plurality of parallel slits to pass through the collimator.

[0005] On one hand, the collimator has a plurality of parallel slits that are equidistant.

[0006] On one hand, for each value of i and each value of j, when the local image (i, j) is captured, (A) intersects with any of the plurality of parallel slits and (B) any plane parallel to any of the plurality of parallel slits intersects with the radiation source.

[0007] In one aspect, the transmission includes: moving the collimator relative to the scene when the radiation source is stationary relative to the scene.

[0008] In one aspect, the transmission includes: moving the radiation source and the collimator relative to the scene when the radiation source and the collimator are stationary relative to each other.

[0009] On one hand, the capture is performed using an image sensor, such that the radiation beams (i, j), i = 1, ..., M and j = 1, ..., Ni reach the scene before reaching the image sensor, and the image sensor includes an effective region for capturing all the local images (i, j), i = 1, ..., M and j = 1, ..., Ni.

[0010] On the one hand, all Ni, i=1, ..., M are the same.

[0011] On one hand, for each value of i, the stitched local image (i, j), j = 1, ..., Ni, is formed based on the relative positions of all the fan-shaped radiation beams of the radiation beam group (i, j), j = 1, ..., Ni with respect to each other.

[0012] This document discloses an imaging system comprising: a radiation beam generator configured to transmit radiation beam groups (i,j), i = 1, ..., M and j = 1, ..., Ni, to the same scene, wherein M and Ni, i = 1, ..., M are integers greater than 1; wherein each of the radiation beam groups (i,j), i = 1, ..., M and j = 1, ..., Ni includes a plurality of parallel fan-shaped radiation beams transmitted simultaneously; wherein for each value of i, the fan-shaped radiation beams of the radiation beam groups (i,j), j = 1, ..., Ni are parallel to each other; wherein for each value of i, the radiation beam groups (i,j), j = 1, ..., Ni are transmitted one group at a time; and wherein for any of 1, ..., M... For different i1 and i2, the radiation particle paths of any two corresponding radiation beam groups (i1,j), i=1, ..., Ni1 and radiation beam group (i2,j), j=1, ..., Ni2 in the radiation beam groups (i,j), i=1, ..., M and j=1, ..., Ni are not parallel to each other; and an image sensor is configured to capture a local image (i,j) of the scene with the radiation of the radiation beam group (i,j) for i=1, ..., M and j=1, ..., Ni, and for each value of i, stitch the local image (i,j), j=1, ..., Ni to obtain a stitched image (i) of the scene, and reconstruct a 3D image of the scene from the stitched image (i), i=1, ..., M.

[0013] In one aspect, the radiation beam generator includes a radiation source and a collimator, and for each value of i, the collimator is configured to (A) be between the radiation source and the scene and (B) translate in a normal direction (i) perpendicular to the radiation beam group (i, j), j = 1, ..., Ni.

[0014] In one aspect, the collimator includes a plurality of parallel slits configured to allow radiation from the radiation source incident on and parallel to the plurality of parallel slits to pass through the collimator.

[0015] On one hand, the collimator has a plurality of parallel slits that are equidistant.

[0016] On one hand, for each value of i and each value of j, when the image sensor captures the local image (i, j), (A) intersects with any of the plurality of parallel slits and (B) any plane parallel to any of the plurality of parallel slits intersects with the radiation source.

[0017] In one respect, the collimator is configured to move relative to the scene when the radiation source is stationary relative to the scene.

[0018] In one respect, the radiation source and the collimator are configured to move relative to the scene when the radiation source and the collimator are stationary relative to each other.

[0019] In one aspect, the image sensor includes an effective region configured to capture all of the local images (i, j), i = 1, ..., M and j = 1, ..., Ni.

[0020] On the one hand, all Ni, i=1, ..., M are the same.

[0021] On one hand, for each value of i, the image sensor is configured to stitch together the local image (i, j), j = 1, ..., Ni, based on the relative positions of all the fan-shaped radiation beams of the radiation beam group (i, j), j = 1, ..., Ni relative to each other. [Attached Image Description]

[0022] Figure 1 A radiation detector according to an embodiment is illustrated schematically.

[0023] Figure 2A A simplified cross-sectional view of a radiation detector according to an embodiment is shown schematically.

[0024] Figure 2B A detailed cross-sectional view of a radiation detector according to an embodiment is schematically shown.

[0025] Figure 2C A detailed cross-sectional view of a radiation detector according to an alternative embodiment is schematically shown.

[0026] Figure 3 A top view schematically illustrating a package including a radiation detector and a printed circuit board (PCB) according to an embodiment is shown.

[0027] Figure 4 The illustration schematically depicts, according to an embodiment, components including those mounted to a system PCB (printed circuit board). Figure 3 A cross-sectional view of the packaged image sensor.

[0028] Figures 5A to 7C The illustration shows the use according to an embodiment. Figure 4 Imaging sessions of image sensors.

[0029] Figure 8 A flowchart summarizing the imaging session is shown.

[0030] Figures 9 to 10 The diagram illustrates how the radiation beams used in imaging sessions, according to different embodiments, are generated.

Detailed Implementation Methods

[0031] Radiation detector

[0032] As an example, Figure 1 A radiation detector 100 is schematically shown. The radiation detector 100 may include an array of pixels 150 (also referred to as sensing elements 150). This array may be a rectangular array (such as...). Figure 1 (as shown), cellular array, hexagonal array, or any other suitable array. Figure 1 The example of a 150-pixel array has 4 rows and 7 columns; however, in general, a 150-pixel array can have any number of rows and any number of columns.

[0033] Each pixel 150 can be configured to detect radiation incident upon it from a radiation source (not shown) and can be configured to measure characteristics of the radiation (e.g., particle energy, wavelength, and frequency). The radiation can include particles, such as photons and subatomic particles. Each pixel 150 can be configured to count the number of radiant particles incident upon it over a period of time, with energy falling into multiple energy ranges. All pixels 150 can be configured to count the number of radiant particles incident upon it within multiple energy ranges simultaneously over the same period of time. When the incident radiant particles have similar energies, pixel 150 can simply be configured to count the number of radiant particles incident upon it over a period of time without measuring the energy of individual radiant particles.

[0034] Each pixel 150 may have its own analog-to-digital converter (ADC) configured to digitize an analog signal representing the energy of an incident radiating particle into a digital signal, or to digitize an analog signal representing the total energy of multiple incident radiating particles into a digital signal. Pixels 150 may be configured to operate in parallel. For example, while one pixel 150 is measuring an incident radiating particle, another pixel 150 may be waiting for the radiating particle to arrive. Pixels 150 do not necessarily need to be individually addressable.

[0035] The radiation detector 100 described herein can be applied to applications such as X-ray telescopes, X-ray mammography, industrial X-ray defect detection, X-ray microscopy or microradiography, X-ray casting inspection, X-ray non-destructive testing, X-ray weld inspection, and X-ray digital subtraction angiography. It may also be suitable to use the radiation detector 100 in place of photographic plates, photographic films, PSP plates, X-ray image intensifiers, scintillators, or other semiconductor X-ray detectors.

[0036] Figure 2AThe illustration schematically shows an embodiment. Figure 1 The radiation detector is shown in a simplified cross-sectional view along line 2A-2A. Specifically, the radiation detector 100 may include a radiation absorbing layer 110 and an electronic device layer 120 (e.g., one or more ASICs or application-specific integrated circuits) for processing or analyzing the electrical signals generated in the radiation absorbing layer 110 by incident radiation. The radiation detector 100 may or may not include a scintillator (not shown). The radiation absorbing layer 110 may contain a semiconductor material, such as silicon, germanium, GaAs, CdTe, CdZnTe, or combinations thereof. The semiconductor material may have a high-quality attenuation coefficient for the radiation of interest.

[0037] As an example, Figure 2B schematically shown Figure 1 A detailed cross-sectional view of the radiation detector 100 along line 2A-2A. Specifically, the radiation absorption layer 110 may include one or more diodes (e.g., pin or pn) formed by one or more discrete regions 114 of a first doped region 111 and a second doped region 113. The second doped region 113 may be separated from the first doped region 111 by an optional intrinsic region 112. The discrete regions 114 may be separated from each other by either the first doped region 111 or the intrinsic region 112. The first doped region 111 and the second doped region 113 may have opposite types of doping (e.g., region 111 is p-type and region 113 is n-type, or region 111 is n-type and region 113 is p-type). Figure 2B In the example, each discrete region 114 of the second doped region 113 forms a diode with the first doped region 111 and an optional intrinsic region 112. That is, in Figure 2B In the example, the radiation-absorbing layer 110 has multiple diodes (more specifically, 7 diodes correspond to...). Figure 1 In the array, each row has 7 pixels, 150. For simplicity, Figure 2B Only two pixels 150 are marked in the image. Multiple diodes may have an electrode 119A as a common electrode. The first doped region 111 may also have discrete portions.

[0038] Electronics layer 120 may include electronic systems 121 suitable for processing or interpreting signals generated by radiation incident on radiation-absorbing layer 110. Electronic systems 121 may include analog circuitry such as filter networks, amplifiers, integrators, and comparators, or digital circuitry such as microprocessors and memories. Electronic systems 121 may include one or more ADCs (analog-to-digital converters). Electronic systems 121 may include components shared by pixels 150 or components dedicated to a single pixel 150. For example, electronic systems 121 may include amplifiers dedicated to each pixel 150 and microprocessors shared among all pixels 150. Electronic systems 121 may be electrically connected to pixels 150 via vias 131. The space between vias may be filled with filler material 130, which may increase the mechanical stability of the connection between electronics layer 120 and radiation-absorbing layer 110. Other bonding techniques may connect electronics 121 to pixels 150 without using vias 131.

[0039] When radiation from a radiation source (not shown) impacts the radiation-absorbing layer 110 of a diode, the radiation particles can be absorbed and generate one or more charge carriers (e.g., electrons, holes) through various mechanisms. These charge carriers can drift to an electrode of one of the diodes under an electric field. This electric field can be an external electric field. Electrical contacts 119B can include discrete portions, each of which is in electrical contact with a discrete region 114. The term "electrical contact" is used interchangeably with the term "electrode." In embodiments, charge carriers can drift in various directions such that charge carriers generated by a single radiation particle are substantially not shared by two different discrete regions 114 (here, "substantially not shared" means that less than 2%, less than 0.5%, less than 0.1%, or less than 0.01% of these charge carriers flow to a different discrete region 114 compared to the remaining charge carriers). Charge carriers generated by radiation particles incident around a coverage area of ​​one of these discrete regions 114 are substantially not shared with the other of these discrete regions 114. Pixel 150 associated with discrete region 114 can be a region surrounding discrete region 114 in which substantially all (greater than 98%, greater than 99.5%, greater than 99.9%, or greater than 99.99%) of the charge carriers generated by incident radiating particles flow to discrete region 114. That is, less than 2%, less than 1%, less than 0.1%, or less than 0.01% of these charge carriers flow through pixel 150.

[0040] Figure 2C A schematic illustration is shown according to an alternative embodiment. Figure 1A detailed cross-sectional view of the radiation detector 100 along line 2A-2A. More specifically, the radiation absorbing layer 110 may comprise resistors of semiconductor materials such as silicon, germanium, GaAs, CdTe, CdZnTe, or combinations thereof, but not diodes. This semiconductor material may have a high-quality attenuation coefficient for the radiation of interest. In an embodiment, Figure 2C The electronic device layer 120 is similar in structure and function to Figure 2B The electronic device layer 120.

[0041] When radiation impacts the radiation-absorbing layer 110, which includes resistors but not diodes, it can be absorbed and generate one or more charge carriers through various mechanisms. The radiating particles can generate 10 to 100,000 charge carriers. These charge carriers can drift to electrical contacts 119A and 119B under an electric field. This electric field can be an external electric field. Electrical contact 119B can include discrete portions. In embodiments, charge carriers can drift in various directions such that charge carriers generated by a single radiating particle are substantially not shared by the two distinct discrete portions of electrical contact 119B (here, "substantially not shared" means that less than 2%, less than 0.5%, less than 0.1%, or less than 0.01% of these charge carriers flow to a different discrete portion compared to the remaining charge carriers). Charge carriers generated by radiating particles incident on the coverage area of ​​one of these discrete portions of electrical contact 119B are substantially not shared with the other of these discrete portions of electrical contact 119B. Pixel 150 associated with a discrete portion of electrical contact 119B can be a region surrounding the discrete portion, in which substantially all (greater than 98%, greater than 99.5%, greater than 99.9%, or greater than 99.99%) of the charge carriers generated by incident radiant particles flow toward the discrete portion of electrical contact 119B. That is, less than 2%, less than 0.5%, less than 0.1%, or less than 0.01% of these charge carriers flow through a pixel associated with a discrete portion of electrical contact 119B.

[0042] Radiation detector packaging

[0043] Figure 3A schematic top view of a package 200 including a radiation detector 100 and a printed circuit board (PCB) 400 is shown. The term "PCB" as used herein is not limited to a particular material. For example, a PCB may include semiconductors. The radiation detector 100 may be mounted to the PCB 400. For clarity, wiring between the radiation detector 100 and the PCB 400 is not shown. The PCB 400 may have one or more radiation detectors 100. The PCB 400 may have an area 405 not covered by the radiation detector 100 (e.g., for accommodating bonding wires 410). The radiation detector 100 may have pixels 150 (…). Figure 1 The effective area 190 is where the radiation detector 100 is located. The radiation detector 100 may have a peripheral area 195 near the edge of the radiation detector 100. The peripheral area 195 has no pixels 150, and the radiation detector 100 does not detect radiation particles incident on the peripheral area 195.

[0044] Image sensor

[0045] Figure 4 A cross-sectional view of an image sensor 490 according to an embodiment is schematically shown. The image sensor 490 may include one or more sensors mounted to a system PCB 450. Figure 3 The package size is 200. As an example. Figure 4 Two packages 200 are shown. Electrical connections between the PCB 400 and the system PCB 450 can be achieved via bonding wires 410. To accommodate the bonding wires 410 on the PCB 400, the PCB 400 may have an area 405 not covered by the radiation detector 100. To accommodate the bonding wires 410 on the system PCB 450, there may be gaps between the packages 200. The gaps may be greater than approximately 1 mm. Radiation particles incident on the peripheral area 195, area 405, or gaps cannot be detected by the packages 200 on the system PCB 450. The dead zone of a radiation detector (e.g., radiation detector 100) is an area on the radiation-receiving surface of the radiation detector that cannot be detected by that radiation detector. The dead zone of a package (e.g., package 200) is an area on the radiation-receiving surface of the package that cannot be detected by one or more radiation detectors within the package. Figure 3 and Figure 4 In the example shown, the dead zone of package 200 includes peripheral area 195 and area 405. The dead zone (e.g., image sensor 490) of an image sensor having a set of packages (e.g., packages 200 mounted on the same PCB and arranged in the same or different layers) includes a combination of the dead zones of each package in the set and the gaps between the packages. In an embodiment, package 200 itself ( Figure 3 It can be considered an image sensor.

[0046] The image sensor 490, including the radiation detector 100, may have a dead zone 488 that cannot detect incident radiation. However, the image sensor 490 may capture multiple partial images of an object or scene (not shown), which can then be stitched together to form an image of the entire object or scene.

[0047] Imaging System - Initial Setup

[0048] Figure 5A A perspective view of an imaging system 500 according to an embodiment is schematically shown. In this embodiment, the imaging system 500 may include a radiation beam generator 510 and an image sensor 490. For simplicity, only the effective area 190 of the image sensor 490 is shown. In this embodiment, an object 532 may be located in a scene 530 between the radiation beam generator 510 and the image sensor 490.

[0049] First local image capture

[0050] In an embodiment, a first imaging session using image sensor 490 to image scene 530 (including object 532) may begin with a first image capture as follows. When imaging system 500 is in a state such as Figure 5A In the first system arrangement shown, the radiation beam generator 510 can simultaneously send two fan-shaped radiation beams 511a and 511b to the scene 530. In the embodiment, as Figure 5A As shown, the two sector-shaped radiation beams 511a and 511b can be parallel to each other.

[0051] In this embodiment, the two fan-shaped radiation beams 511a and 511b can fall completely on the effective area 190 after passing through the scene 530 including the object 532. Using the incident radiation from the two fan-shaped radiation beams 511a and 511b, the effective area 190 of the image sensor 490 can capture a first partial image 611 of the scene 530. Figure 6A ).

[0052] Reference Figure 5A and Figure 6AThe first partial image 611 of scene 530 may include (A) a non-signal region 611ns, which in an embodiment may include image elements of pixels 150 corresponding to the effective region 190 that does not receive incident radiation from the fan-shaped radiation beams 511a and 511b, and (B) two signal regions 611a and 611b, which in an embodiment may include image elements of pixels 150 corresponding to the effective region 190 that receives incident radiation from the fan-shaped radiation beams 511a and 511b (in other words, signal regions 611a and 611b are images of the fan-shaped radiation beams 511a and 511b, respectively). The two signal regions 611a and 611b respectively include partial images 611ai and 611bi of object 532.

[0053] Second local image capture

[0054] In one embodiment, after capturing a first local image 611 in the effective area 190 of the image sensor 490, the imaging system 500 can be transformed into, as follows: Figure 5B The second system arrangement shown allows for the second local image capture of the first imaging session to be performed as follows. Specifically, refer to... Figure 5B When the imaging system 500 is in the second system arrangement, the radiation beam generator 510 can simultaneously send two fan-shaped radiation beams 512a and 512b to the scene 530. In an embodiment, the two fan-shaped radiation beams 512a and 512b can be parallel to each other and parallel to the fan-shaped radiation beams 511a and 511b. Figure 5A ).

[0055] In an embodiment, the portion of scene 530 illuminated by the two fan-shaped radiation beams 512a and 512b may differ from the portion of scene 530 illuminated by the two fan-shaped radiation beams 511a and 511b. In an embodiment, just as... Figure 5A The two fan-shaped radiation beams 511a and 511b and the image sensor 490 are treated as a single object in the direction 502 perpendicular to the normal of the two fan-shaped radiation beams 511a and 511b. Figure 5A Translate upwards (i.e., each point moves in the same direction and by the same distance), and then each becomes... Figure 5B The two fan-shaped radiation beams 512a and 512b are the same as the image sensor 490.

[0056] In this embodiment, the two fan-shaped radiation beams 512a and 512b can fall completely on the effective area 190 after passing through the scene 530 including the object 532. Using the incident radiation from the two fan-shaped radiation beams 512a and 512b, the effective area 190 of the image sensor 490 can capture a second partial image 612 of the scene 530. Figure 6B ).

[0057] Reference Figure 5B and Figure 6B The second partial image 612 of scene 530 may include: (A) a non-signal region 612ns, which, in an embodiment, may include image elements of pixels 150 corresponding to the effective region 190 that does not receive incident radiation from the fan-shaped radiation beams 512a and 512b; and (B) two signal regions 612a and 612b, which, in an embodiment, may include image elements of pixels 150 corresponding to the effective region 190 that receives incident radiation from the fan-shaped radiation beams 512a and 512b (in other words, signal regions 612a and 612b are images of the fan-shaped radiation beams 512a and 512b, respectively). The two signal regions 612a and 612b respectively include partial images 612ai and 612bi of object 532.

[0058] Third local image capture

[0059] In one embodiment, after capturing the second local image 612 in the effective area 190 of the image sensor 490, the imaging system 500 can be transformed as follows: Figure 5C The third system arrangement shown can then be used to perform a third local image capture of the first imaging session as follows. Specifically, in the embodiment, refer to... Figure 5C When the imaging system 500 is in the third system arrangement, the radiation beam generator 510 can simultaneously send two fan-shaped radiation beams 513a and 513b to the scene 530. In an embodiment, the two fan-shaped radiation beams 513a and 513b can be parallel to each other and parallel to the fan-shaped radiation beams 512a and 512b. Figure 5B ).

[0060] In an embodiment, the portion of scene 530 illuminated by the two fan-shaped radiation beams 513a and 513b may differ from the portion of scene 530 illuminated by the fan-shaped radiation beams 511a, 512b, 512a, and 512b. In an embodiment, just as... Figure 5B The two fan-shaped radiation beams 512a and 512b, along with the image sensor 490, are translated as a single object in a direction 502 perpendicular to the normals of the two fan-shaped radiation beams 512a and 512b, and then respectively become Figure 5C The two fan-shaped radiation beams 513a and 513b are the same as the image sensor 490.

[0061] In this embodiment, the two fan-shaped radiation beams 513a and 513b, after passing through the scene 530 including the object 532, can fall completely on the effective area 190. Using the incident radiation from the two fan-shaped radiation beams 513a and 513b, the effective area 190 of the image sensor 490 can capture a third partial image 613 of the scene 530. Figure 6C ).

[0062] Reference Figure 5C and Figure 6C The third partial image 613 of scene 530 may include: (A) a non-signal region 613ns, which, in an embodiment, may include image elements of pixels 150 corresponding to the effective region 190 that does not receive incident radiation from the fan-shaped radiation beams 513a and 513b; and (B) two signal regions 613a and 613b, which, in an embodiment, may include image elements of pixels 150 corresponding to the effective region 190 that receives incident radiation from the fan-shaped radiation beams 513a and 513b (in other words, signal regions 613a and 613b are images of the fan-shaped radiation beams 513a and 513b, respectively). The two signal regions 613a and 613b respectively include partial images 613ai and 613bi of object 532.

[0063] stitching together local images

[0064] In the embodiments, reference is made to Figures 5A to 6D After capturing the third partial image 613 of scene 530 in the effective area 190 of image sensor 490, image sensor 490 can stitch these three partial images 611, 612, and 613 to obtain the first stitched image 630 of scene 530. Figure 6D The first stitched image 630 includes a stitched image 632 of object 532.

[0065] In this embodiment, the stitching of three local images 611, 612, and 613 can be performed as follows. First, the image sensor 490 can determine (A) the signal regions 611a and 611b of the first local image 611. Figure 6A (B) Signal regions 612a and 612b of the second local image 612 Figure 6B (C) Signal regions 613a and 613b of the third local image 613 Figure 6C Determining the signal region of a local image means determining all graphic elements within that signal region. In an embodiment, determining the signal region of a local image may include determining some or all image elements along the boundary line of the signal region. In an embodiment, determining the image elements along the boundary line of the signal region may include analyzing image elements near the boundary line. When crossing the boundary line, the signal value of the image element should change abruptly; this phenomenon should facilitate the selection of image elements as image elements along the boundary line.

[0066] Next, in this embodiment, after determining signal regions 611a, 611b, 612a, 612b, 613a, and 613b, the image sensor 490 can align the determined signal regions 611a, 611b, 612a, 612b, 613a, and 613b to form a first stitched image 630 of scene 530. Figure 6DIn an embodiment, the alignment of the signal regions 611a, 611b, 612a, 612b, 613a and 613b mentioned above can be based on the relative positions of the fan-shaped radiation beams 511a, 511b, 512a, 512b, 513a and 513b relative to each other.

[0067] Repeat from different angles

[0068] In an embodiment, after capturing the third partial image 613, a second imaging session similar to the first imaging session can be performed, but at a different angle. Here, "at a different angle" means that there is no (A) first radiation particle path of the fan-shaped radiation beam used in the first imaging session, and (B) second radiation particle path of the fan-shaped radiation beam used in the second imaging session, such that the first radiation particle path and the second radiation particle path are parallel to each other. If at least one radiation particle of the radiation beam follows or propagates along a radiation particle path, then that radiation particle path belongs to that radiation beam.

[0069] In an embodiment, the second imaging session may include fourth, fifth, and sixth local image captures, which are respectively similar to the first, second, and third local image captures of the first imaging session described above. More specifically, in an embodiment, during the fourth local image capture of the second imaging session, the radiation beam generator 510 may simultaneously generate two parallel fan-shaped radiation beams 721a and 721b. Figure 7A Using the radiation from the two fan-shaped radiation beams 721a and 721b that have passed through scene 530, the effective area 190 of image sensor 490 can capture a fourth partial image (not shown) of scene 530.

[0070] Next, in an embodiment, during the fifth local image capture of the second imaging session, the radiation beam generator 510 can simultaneously generate two parallel fan-shaped radiation beams 721a and 721b. Figure 7A Two parallel fan-shaped radiation beams, 722a and 722b. Figure 7B Using the radiation from the two fan-shaped radiation beams 722a and 722b that have passed through scene 530, the effective area 190 of image sensor 490 can capture a fifth partial image (not shown) of scene 530.

[0071] Next, in an embodiment, during the sixth local image capture of the second imaging session, the radiation beam generator 510 can simultaneously generate two parallel fan-shaped radiation beams 722a and 722b. Figure 7B Two parallel fan-shaped radiation beams, 723a and 723b. Figure 7CUsing the radiation from the two fan-shaped radiation beams 723a and 723b that have passed through scene 530, the effective area 190 of image sensor 490 can capture a sixth partial image (not shown) of scene 530.

[0072] Next, in this embodiment, the image sensor 490 can stitch together the fourth, fifth, and sixth partial images of scene 530 to obtain a second stitched image of scene 530. In this embodiment, the stitching of the fourth, fifth, and sixth partial images of scene 530 can be similar to the stitching of the first, second, and third partial images of scene 530 (611, 612, and 613, respectively) described above.

[0073] 3D image reconstruction

[0074] Next, in an embodiment, the image sensor 490 can obtain data from the first stitched image 630 ( Figure 6D The second stitched image (not shown) is used to reconstruct a 3D image of scene 530.

[0075] Summary

[0076] Figure 8 A flowchart 800 summarizing the operation of the imaging system 500 described above is shown. In step 810, radiation beam groups (i, j), i = 1, ..., M and j = 1, ..., Ni, are sent to the same scene, where M and Ni, i = 1, ..., M are integers greater than 1. For example, in the above embodiment, M = 2, N1 = N2 = 3. Specifically, radiation beam groups (1,1), (1,2), (1,3), (2,1), (2,2), and (2,3) are radiation beam groups 511a+511b, 512a+512b, 513a+513b, 721a+721b, 722a+722b, and 723a+723b sent to the same scene 530, respectively.

[0077] Additionally, each of the radiation beam groups (i, j), i = 1, ..., M and j = 1, ..., Ni, comprises multiple parallel sector radiation beams that are transmitted simultaneously. For example, radiation beam group (1, 1) includes two parallel sector radiation beams 511a and 511b that are transmitted simultaneously. Figure 5A As another example, the radiation beam group (2, 3) includes two parallel sector radiation beams 723a and 723b that are transmitted simultaneously. Figure 7C ).

[0078] Furthermore, for each value of i, the sector radiation beams of the radiation beam group (i, j), j = 1, ..., Ni, are parallel to each other. For example, in the above embodiment with M = 2 and N1 = N2 = 3, for i = 1 and j = 1, 2, 3, the sector radiation beams 511a, 511b, 512a, 512b, 513a, and 513b are parallel to each other. For i = 2 and j = 1, 2, 3, the sector radiation beams 721a, 721b, 722a, 722b, 723a, and 723b are parallel to each other.

[0079] Furthermore, for each value of i, the radiation beam group (i, j), j = 1, ..., Ni, is transmitted one group at a time. For example, in the above embodiment where M = 2 and N1 = N2 = 3, for i = 1, the radiation beam group 511a + 511b ( Figure 5A ), Radiation beam group 512a+512b ( Figure 5B ) and radiation beam groups 513a+513b ( Figure 5C One group is sent at a time. For i=2, the radiation beam group is 721a+721b. Figure 7A ), Radiation beam group 722a+722b ( Figure 7B ) and radiation beam groups 723a+723b ( Figure 7C Send one group at a time.

[0080] Furthermore, for any different i1 and i2 in 1, ..., M, the radiation particle paths of any two of the corresponding radiation beam groups (i1,j), i=1, ..., Ni1 and radiation beam groups (i2,j), j=1, ..., Ni2 in the radiation beam groups (i,j), i=1, ..., M and j=1, ..., Ni are not parallel to each other. For example, in the case of M=2 and N1=N2=3 and i1=1 and i2=2 in the above embodiment, there are no (A) fan-shaped radiation beams 511a, 511b, 512a, 512b, 513a and 513b that make the first radiation particle path and the second radiation particle path parallel to each other. Figures 5A to 5C The first radiation particle path of (B) and the fan-shaped radiation beams 721a, 721b, 722a, 722b, 723a and 723b. Figures 7A to 7C The second radiation particle path.

[0081] In step 820, for i = 1, ..., M and j = 1, ..., Ni, a local image (i, j) of the scene is captured using radiation from a radiation beam group (i, j). For example, in the case of i = 1 and j = 1, a fan-shaped radiation beam 511a and 511b is used. Figure 5A Local image of radiation capture of radiation beam group (1,1) 611 ( Figure 6A As another example, in the case of i=1 and j=2, using fan-shaped radiation beams 512a and 512b ( Figure 5B Local radiation capture images of radiation beam groups (1, 2) 612 ( Figure 6B ).

[0082] In step 830, for each value of i, local images (i, j), j = 1, ..., Ni, are stitched together to obtain a stitched image (i) of the scene. For example, in the above embodiment, when M = 2 and N1 = N2 = 3, and for i = 1, refer to... Figures 6A to 6D The local images 611, 612, and 613 are stitched together to obtain the first stitched image 630 of scene 530. As another example, for i=2, the fourth, fifth, and sixth local images (not shown) are stitched together to obtain the second stitched image (not shown) of scene 530.

[0083] In step 840, a 3D image of the scene is reconstructed from the stitched images (i), i = 1, ..., M. For example, in the above embodiment where M = 2 and N1 = N2 = 3, as described above, from the first stitched image 630 of scene 530 (i... Figure 6D The second stitched image (not shown) of scene 530 is used to reconstruct the 3D image of scene 530.

[0084] collimator

[0085] In the embodiments, reference is made to Figure 9 The radiation beam generator 510 may include a radiation source 810 and a collimator 820. In an embodiment, the collimator 820 may include two parallel slits 821 and 822. In an embodiment, the beam can be generated as follows: Figure 5A Parallel sector-shaped radiation beams 511a and 511b are generated. Specifically, radiation source 810 can send radiation 817 to collimator 820. In an embodiment, some portions of radiation 817 incident on and parallel to the two parallel slits 821 and 822 can be allowed to pass through collimator 820, thereby obtaining parallel sector-shaped radiation beams 511a and 511b, respectively. In an embodiment, radiation source 810 may include a metal rod bombarded by an electron beam (not shown).

[0086] In this embodiment, it can be generated as follows: Figure 5B The parallel fan-shaped radiation beams 512a and 512b. First, Figure 9The collimator 820 can be translated in the normal direction 824, perpendicular to the parallel sector radiation beams 511a and 511b, to a new position in the second system arrangement. Then, in an embodiment, some portions of the radiation 817 incident on and parallel to the two parallel slits 821 and 822 can be allowed to pass through the collimator 820, resulting in parallel sector radiation beams 512a and 512b. In an embodiment, the radiation source 810 can remain stationary relative to the scene 530 as the collimator 820 is translated to its new position in the second system arrangement. In an alternative embodiment, the radiation source 810 and the collimator 820 can be translated as a single object in the normal direction 824 to their new positions in the second system arrangement.

[0087] In an embodiment, Figure 5C The parallel fan-shaped radiation beams 513a and 513b can be used to generate Figure 5B The parallel fan-shaped radiation beams 512a and 512b are generated in a similar manner.

[0088] In short, the generation of parallel sector radiation beams 511a, 511b, 512a, 512b, 513a, and 513b may include (A) in the radiation 817 from the radiation source 810, and (B) translating the collimator 820 in a direction 824 perpendicular to the normal direction of all parallel sector radiation beams 511a, 511b, 512a, 512b, 513a, and 513b. In an embodiment, Figures 7A to 7C The parallel sector radiation beams 723a, 721b, 722a, 722b, 723a and 723b can be generated in a manner similar to that used to generate the parallel sector radiation beams 511a, 511b, 512a, 512b, 513a and 513b.

[0089] In one embodiment, the imaging system 500 from Figures 5C to 7A The transformation can include turning Figure 5C The imaging system 500 (including a radiation beam generator 510) rotates about an axis parallel to (A) and Figure 5C The effective region 190 includes the plane where all pixels 150 intersect, and (B) parallel fan-shaped radiation beams 511a, 511b, 512a, 512b, 513a, and 513b. In an alternative embodiment, refer to... Figure 10 The rotation of the imaging system 500 described above does not apply to the radiation source 810 (i.e., the radiation source 810 remains stationary relative to the scene 530). In the embodiment, refer to... Figure 9 and Figure 10When the effective region 190 captures any one of the first, second, third, fourth, fifth, and sixth partial images of scene 530, (A) it intersects with any of the plurality of parallel slits 821 and 822, and (B) any plane parallel to any of the plurality of parallel slits 821 and 822 intersects with the radiation source 810. For example, in Figure 9 In the middle, when the effective region 190 captures the first partial image 611 of scene 530, Figure 6A When ), the plane intersecting slit 821 and parallel to slit 822 intersects the radiation source 810; similarly, the plane intersecting slit 822 and parallel to slit 821 intersects the radiation source 810. In other words, in Figure 9 In the middle, when the effective region 190 captures the first local image 611 of scene 530 ( Figure 6A The plane containing the fan beam 511a intersects with the radiation source 810; similarly, the plane containing the fan beam 511b intersects with the radiation source 810.

[0090] In the above embodiment, the collimator 820 has two parallel slits 821 and 822. Typically, the collimator 820 may have multiple parallel slits (similar to parallel slits 821 and 822). In the embodiment, these multiple parallel slits of the collimator 820 may be equidistant (i.e., the distance between any two adjacent slits is the same).

[0091] Involving multiple effective areas

[0092] In the above embodiment, one effective region 190 captures all local images of scene 530. In an alternative embodiment, two or more effective regions 190 may capture local images of scene 530. For an example of this alternative embodiment, Figure 5B Effective area 190 (capture) Figure 6B The second local image 612) may be different from Figure 5A Effective area 190 (capture) Figure 6A The first partial image 611).

[0093] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for illustrative purposes and are not intended to be limiting; the true scope and spirit are indicated by the appended claims.

Claims

1. An imaging method, comprising: Send radiation beams (i,j), i=1, ...,M and j=1, ...,Ni, to the same scene. Where M and Ni, i = 1, ..., M are integers greater than 1. Wherein, each of the radiation beam groups (i, j), i = 1, ..., M and j = 1, ..., Ni, comprises multiple parallel fan-shaped radiation beams transmitted simultaneously. Wherein, for each value of i, the sector radiation beams of the radiation beam group (i, j), j = 1, ..., Ni are parallel to each other. Wherein, for each value of i, the radiation beam group (i, j), j = 1, ..., Ni, is transmitted one group at a time, and Wherein, for any different i1 and i2 in 1, ..., M, any two radiation particle paths in the corresponding radiation beam groups (i1,j), i=1, ..., Ni1 and radiation beam groups (i2,j), j=1, ..., Ni2 in the radiation beam groups (i,j), i=1, ..., M and j=1, ..., Ni are not parallel to each other; For i = 1, ..., M and j = 1, ..., Ni, a local image (i, j) of the scene is captured using the radiation from the radiation beam group (i, j); For each value of i, the local images (i, j), j = 1, ..., Ni, are stitched together to obtain the stitched image (i) of the scene; and A 3D image of the scene is reconstructed from the stitched image (i), i = 1, ..., M.

2. The imaging method according to claim 1, wherein, For each value of i, sending the radiation beam group (i, j), j = 1, ..., Ni to the same scene includes: (A) between the same radiation source and the scene and (B) translating the same collimator in the normal direction (i) perpendicular to the radiation beam group (i, j).

3. The imaging method according to claim 2, wherein, The collimator includes a plurality of parallel slits configured to allow radiation from the radiation source incident on and parallel to the plurality of parallel slits to pass through the collimator.

4. The imaging method according to claim 3, wherein, The collimator has multiple parallel slits that are equidistant.

5. The imaging method according to claim 3, wherein, For each value of i and each value of j, when the local image (i, j) is captured, (A) intersects with any of the plurality of parallel slits and (B) any plane parallel to any of the plurality of parallel slits intersects with the radiation source.

6. The imaging method according to claim 2, wherein, The transmission includes: moving the collimator relative to the scene when the radiation source is stationary relative to the scene.

7. The imaging method according to claim 2, wherein, The transmission includes: moving the radiation source and the collimator relative to the scene when the radiation source and the collimator are stationary relative to each other.

8. The imaging method according to claim 1, in, The capture is performed using an image sensor, such that the radiation beam groups (i, j), i = 1, ..., M and j = 1, ..., Ni, arrive at the scene before reaching the image sensor, and The image sensor includes an effective region for capturing all the local images (i, j), i = 1, ..., M and j = 1, ..., Ni.

9. The imaging method according to claim 1, wherein, All Ni, i=1, ..., M are the same.

10. The imaging method according to claim 1, wherein, For each value of i, the stitched local image (i, j), j = 1, ..., Ni, is generated based on the relative positions of all the sector radiation beams of the radiation beam group (i, j), j = 1, ..., Ni with respect to each other.

11. An imaging system, comprising: Configured to send radiation beams (i,j) to the same scene, where i = 1, ..., M and j = 1, ..., Ni, Where M and Ni, i = 1, ..., M are integers greater than 1. Wherein, each of the radiation beam groups (i, j), i = 1, ..., M and j = 1, ..., Ni, comprises multiple parallel fan-shaped radiation beams transmitted simultaneously. Wherein, for each value of i, the sector radiation beams of the radiation beam group (i, j), j = 1, ..., Ni are parallel to each other. Wherein, for each value of i, the radiation beam group (i, j), j = 1, ..., Ni, is transmitted one group at a time, and Wherein, for any different i1 and i2 in 1, ..., M, any two radiation particle paths in the corresponding radiation beam groups (i1,j), i=1, ..., Ni1 and radiation beam group (i2,j), j=1, ..., Ni2 are not parallel to each other; and The image sensor is configured to, For i = 1, ..., M and j = 1, ..., Ni, a local image (i, j) of the scene is captured using the radiation from the radiation beam group (i, j). For each value of i, the local images (i, j), j = 1, ..., Ni, are stitched together to obtain the stitched image (i) of the scene. A 3D image of the scene is reconstructed from the stitched image (i), i = 1, ..., M.

12. The imaging system according to claim 11, in, The radiation beam generator includes a radiation source and a collimator, and For each value of i, the collimator is configured to (A) be between the radiation source and the scene and (B) translate in the normal direction (i) perpendicular to the radiation beam group (i, j), j = 1, ..., M.

13. The imaging system according to claim 12, wherein, The collimator includes a plurality of parallel slits configured to allow radiation from the radiation source incident on and parallel to the plurality of parallel slits to pass through the collimator.

14. The imaging system according to claim 13, wherein, The collimator has multiple parallel slits that are equidistant.

15. The imaging system according to claim 13, wherein, For each value of i and each value of j, when the image sensor captures the local image (i, j), (A) intersects with any of the plurality of parallel slits and (B) any plane parallel to any of the plurality of parallel slits intersects with the radiation source.

16. The imaging system according to claim 12, wherein, The collimator is configured to move relative to the scene when the radiation source is stationary relative to the scene.

17. The imaging system according to claim 12, wherein, The radiation source and the collimator are configured to move relative to the scene when the radiation source and the collimator are stationary relative to each other.

18. The imaging system according to claim 11, wherein, The image sensor includes an effective region configured to capture all the local images (i, j), i = 1, ..., M and j = 1, ..., Ni.

19. The imaging system according to claim 11, wherein, All Ni, i=1, ..., M are the same.

20. The imaging system according to claim 11, wherein, For each value of i, the image sensor is configured to stitch together the local image (i, j), j = 1, ..., Ni, based on the relative positions of all the fan-shaped radiation beams of the radiation beam group (i, j), j = 1, ..., Ni relative to each other.

Images