TW202403528A - Scanning method and apparatus - Google Patents

Abstract

Disclosed herein is a method, comprising: scanning an object with an imaging system that has a radiation detector and a radiation source being stationary with respect to each other. In the scanning, for i=1, ..., M, one value of i at a time in that order, performing scanning (i) by translating the radiation detector along a same translation plane and along a direction (i). An Ox axis and an Oy axis are both on the translation plane and perpendicular to each other. Orthogonal projections of the directions (i) on the Oy axis do not point in two opposite directions. Orthogonal projections of the directions (i) on the Ox axis point alternatingly in 2 opposite directions. For i=1, ..., (M-1), the direction (i) and the direction (i+1) are not parallel to each other. Each point of the object is scanned by at least two scannings of the scannings.

Description

Scanning methods and devices

The present invention relates to a scanning method and device.

A radiation detector is a device that measures the characteristics of radiation. Examples of such properties may include the intensity, phase, and spatial distribution of polarization of the radiation. The radiation measured by the radiation detector may be radiation that has passed through the object. The radiation measured by the radiation detector may be electromagnetic radiation, such as infrared light, visible light, ultraviolet light, X-rays or gamma rays. Radiation can be of other types such as alpha rays and beta rays. An imaging system may include one or more image sensors, each of which may have one or more radiation detectors.

Disclosed herein is a method comprising scanning an object with an imaging system including a radiation detector and a radiation source stationary relative to each other. The scanned object includes: for i=1,...,M, sequentially one value of i at a time, by translating the radiation detector (A) along the same translation plane and (B) in direction (i) to perform scan(i). M is an integer greater than 1. The Ox axis and the Oy axis are both on the translation plane and perpendicular to each other. The orthogonal projection of the direction (i), i=1,...,M on the Oy axis does not point to two opposite directions. In the direction (i), the orthogonal projections of i=1,...,M on the Ox axis point alternately in two opposite directions. For i=1, ..., (M-1), the direction (i) and the direction (i+1) are not parallel to each other. Each point of the object is scanned by at least two of the scans (i), i=1,...,M.

In one aspect, for i=1, ..., (M-2), said direction (i) and said direction (i+2) are parallel to each other.

In one aspect, each point is scanned by no more than 2 of said scans (i), i=1,...,M.

In one aspect, the translation plane either (A) intersects all source-facing sensing elements of the radiation detector, or (B) is a best approximation of all source-facing sensing elements of the radiation detector. Combined plane.

In one aspect, at a point in time during said scan (i), i=1,...,M, said translation plane is perpendicular to an orientation of said radiation source and said radiation detector. The straight line where the source and sensing elements intersect.

In one aspect, the sensing element plane of the radiation detector intersects the radiation source.

In one aspect, for each odd value of i, the scanning (i) includes sending a radiation beam (i) of the same first energy range to the object with the radiation source, and for each even value of i, The scanning (i) includes using the radiation source to send a radiation beam (i) of the same second energy range to the object, the first energy range and the second energy range being different.

In one aspect, the first energy range and the second energy range do not overlap.

In one aspect, for each value of i, the scan (i) includes incrementing a counter of the radiation detector by one in response to a third energy range of radiation particles impacting the radiation detector, and in response to Radiation particles in a fourth energy range impact the radiation detector and are counted down by one using the counter, and the third energy range and the fourth energy range do not overlap.

In one aspect, for each value of i, the scanning (i) includes recording, with a first counter of the radiation detector, a number of radiation particles of a fifth energy range striking a sensing element of the radiation detector. ; and recording, using a second counter of the radiation detector, the number of radiation particles in a sixth energy range that impact the sensing element. The fifth energy range and the sixth energy range do not overlap.

In one aspect, all M translation distances measured in the direction parallel to the Ox axis of scan (i), i=1,...,M respectively, are the same.

In one aspect, for i=1,...,(M-1), (A) the translation distance of the scan (i) in the direction parallel to the Oy axis and (B) the The sum of the translation distances of the scans (i+1) in the direction parallel to the Oy axis does not exceed the size of the radiation detector in the direction parallel to the Oy axis.

In one aspect, for i=1, ..., (M-1), one of the direction (i) and the direction (i+1) is parallel to the Ox axis.

Disclosed herein is an apparatus that includes an imaging system that includes a radiation detector and a radiation source that are stationary relative to each other. The imaging system is configured to scan an object. Scanning of the object by the imaging system includes: for i=1,...,M, one i value at a time in sequence, by (A) along the same translation plane and (B) along the direction (i) Scan (i) is performed by translating the radiation detector. M is an integer greater than 1. The Ox axis and the Oy axis are both on the translation plane and perpendicular to each other. The orthogonal projection of the direction (i), i=1,...,M on the Oy axis does not point to two opposite directions. In the direction (i), the orthogonal projections of i=1,...,M on the Ox axis point alternately in two opposite directions. For i=1, ..., (M-1), the direction (i) and the direction (i+1) are not parallel to each other. Each point of the object is scanned by at least two of the scans (i), i=1,...,M.

In one aspect, for i=1, ..., (M-2), said direction (i) and said direction (i+2) are parallel to each other.

In one aspect, each point is scanned by no more than 2 of said scans (i), i=1,...,M.

In one aspect, the translation plane either (A) intersects all source-facing sensing elements of the radiation detector or (B) is a best approximation of all source-facing sensing elements of the radiation detector. Combined plane.

In one aspect, at a point in time during said scan (i), i=1,...,M, said translation plane is perpendicular to an orientation of said radiation source and said radiation detector. The straight line where the source and sensing elements intersect.

In one aspect, the sensing element plane of the radiation detector intersects the radiation source.

In one aspect, for each odd value of i, the scanning (i) includes sending a radiation beam (i) of the same first energy range to the object with the radiation source, and for each even value of i, The scanning (i) includes using the radiation source to send a radiation beam (i) of the same second energy range to the object, the first energy range and the second energy range being different.

In one aspect, the first energy range and the second energy range do not overlap.

In one aspect, for each value of i, the scan (i) includes incrementing a counter of the radiation detector by one in response to a third energy range of radiation particles impacting the radiation detector, and in response to Radiation particles in a fourth energy range impact the radiation detector and are counted down by one using the counter, and the third energy range and the fourth energy range do not overlap.

In one aspect, for each value of i, the scanning (i) includes recording, with a first counter of the radiation detector, a number of radiation particles of a fifth energy range striking a sensing element of the radiation detector. ; and recording, using a second counter of the radiation detector, the number of radiation particles in a sixth energy range that impact the sensing element. The fifth energy range and the sixth energy range do not overlap.

In one aspect, all M translation distances of said scan (i), i=1,...,M each, measured in a direction parallel to said Ox axis, are the same.

In one aspect, for i=1,...,(M-1), (A) the translation distance of the scan (i) in the direction parallel to the Oy axis and (B) the The sum of the translation distances of the scans (i+1) in the direction parallel to the Oy axis does not exceed the size of the radiation detector in the direction parallel to the Oy axis.

In one aspect, for i=1, ..., (M-1), one of the direction (i) and the direction (i+1) is parallel to the Ox axis.

radiation detector

Figure 1 schematically shows a radiation detector 100 as an example. Radiation detector 100 may include an array of pixels 150 (also referred to as sensing elements 150). The array may be a rectangular array (as shown in Figure 1), a honeycomb array, a hexagonal array, or any other suitable array. The pixel 150 array in the example of Figure 1 has 4 columns and 7 rows; however, in general, the pixel 150 array can have any number of rows and any number of columns.

Each pixel 150 may be configured to detect radiation incident thereon from a radiation source (not shown) and may be configured to measure characteristics of the radiation (eg, energy, wavelength, and frequency of the particles). Radiation may include radiation particles such as photons (X-rays, gamma rays, etc.) and subatomic particles (alpha particles, beta particles, etc.). Each pixel 150 may be configured to count, over a period of time, the number of radiation particles incident thereon whose energy falls within a plurality of energy bins. All pixels 150 may be configured to count the number of radiation particles incident thereon in multiple energy intervals over the same period of time. When the incident radiation particles are of similar energy, the pixel 150 may be configured simply to count the number of radiation particles incident thereon over a period of time without measuring the energy of the individual radiation particles.

Each pixel 150 may have its own analog-to-digital converter (ADC) configured to digitize an analog signal representing the energy of an incident radiation particle into a digital signal, or to digitize an analog signal representing the total energy of multiple incident radiation particles. The signal is digitized into a digital signal. Pixels 150 may be configured for parallel operation. For example, while one pixel 150 is measuring incoming radiation particles, another pixel 150 may be waiting for the radiation particles to arrive. Pixels 150 may not necessarily be individually addressable.

The radiation detector 100 described herein may have a device such as an X-ray telescope, X-ray mammography, industrial X-ray defect detection, X-ray microscopy or microradiography, X-ray casting inspection, Applications such as welding inspection, X-ray digital subtraction angiography, etc. It may be suitable to use the radiation detector 100 in place of a photographic plate, photographic film, PSP plate, X-ray image intensifier, scintillator or other semiconductor X-ray detector.

Figure 2 schematically illustrates a simplified cross-sectional view of the radiation detector 100 of Figure 1 along line 2-2, according to an embodiment. Specifically, the radiation detector 100 may include a radiation absorbing layer 110 and an electronics layer 120 (which may include one or more ASICs or application specific integrated circuits) for processing and analyzing electrical signals generated by incident radiation in the radiation absorbing layer 110 ). Radiation detector 100 may or may not include scintillator (not shown). Radiation absorbing layer 110 may include semiconductor materials such as silicon, germanium, GaAs, CdTe, CdZnTe, or combinations thereof. Semiconducting materials can have high-quality attenuation coefficients for the radiation of interest.

As an example, Figure 3 schematically shows a detailed cross-sectional view of the radiation detector 100 of Figure 1 along line 2-2. Specifically, the radiation absorbing layer 110 may include one or more diodes (eg, p-i-n or p-n) formed by one or more discrete regions 114 of the first doped region 111 , the second doped region 113 . The second doped region 113 may be separated from the first doped region 111 by an optional intrinsic region 112 . Discrete regions 114 may be separated from each other by first doped regions 111 or intrinsic regions 112 . The first doped region 111 and the second doped region 113 may have opposite types of doping (eg, region 111 is p-type and region 113 is n-type, or region 111 is n-type and region 113 is p-type). In the example of FIG. 3 , each discrete region 114 of the second doped region 113 forms a diode with a first doped region 111 and an optional intrinsic region 112 . That is, in the example of FIG. 3 , the radiation absorbing layer 110 has a plurality of diodes (more specifically, 7 diodes corresponding to 7 pixels 150 in one column of the array of FIG. 1 , for simplicity, FIG. Only 2 of these pixels are labeled in 3150). Multiple diodes may have electrical contact 119A as a common (common) electrode. The first doped region 111 may also have discrete portions.

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

When radiation from a radiation source (not shown) strikes the radiation absorbing layer 110 including a diode, the radiation particles may be absorbed and generate one or more charge carriers (eg, electrons, holes) through a variety of mechanisms. Charge carriers can drift to one of the electrodes of the diode under an electric field. The electric field may be an external electric field. Electrical contact 119B may include discrete portions, each discrete portion being in electrical contact with discrete region 114 . The term "electrical contact" may be used interchangeably with the word "electrode". In one embodiment, the charge carriers may drift in all directions such that the charge carriers generated by a single radiating particle are not substantially shared by two different discrete regions 114 (herein "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 location than the remaining charge carriers. discrete area 114). Charge carriers generated by radiation particles incident around the footprint of one of the discrete regions 114 are substantially not shared with another of the discrete regions 114 . Pixels 150 associated with discrete regions 114 may be regions surrounding discrete regions 114 in which substantially all (more than 98%, more than 99.5%, more than 99.9%, or more than 99.99%) of the charge carriers flow to the 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 the pixel 150 .

Figure 4 schematically shows a detailed cross-sectional view along line 2-2 of the radiation detector 100 of Figure 1 according to an alternative embodiment. More specifically, radiation absorbing layer 110 may include resistors of semiconductor materials such as silicon, germanium, GaAs, CdTe, CdZnTe, or combinations thereof, but not diodes. Semiconducting materials can have high-quality attenuation coefficients for the radiation of interest. In one embodiment, the electronic device layer 120 of FIG. 4 is similar in structure and function to the electronic device layer 120 of FIG. 3 .

When radiation strikes the radiation absorbing layer 110, which includes a resistor but not a diode, it can be absorbed and produce one or more charge carriers through a variety of mechanisms. Radiating particles can produce anywhere from 10 to 100,000 charge carriers. Charge carriers can drift to electrical contacts 119A and 119B under the electric field. The electric field may be an external electric field. Electrical contacts 119B may include discrete portions. In one embodiment, the charge carriers may drift in all directions such that the charge carriers generated by a single radiated particle are not substantially shared by two different discrete portions of electrical contact 119B (herein "substantially not" ...shared" means less than 2%, less than 0.5%, less than 0.1% or less than 0.01% of the charge carriers compared to the remaining charge carriers subflow to a different discrete part). Charge carriers generated by radiation particles incident around the footprint of one of the discrete portions of electrical contact 119B are substantially not shared with another of the discrete portions of electrical contact 119B. A pixel 150 associated with a discrete portion of electrical contact 119B may be an area surrounding the discrete portion in which substantially all (more than 98%, more than 99.5%, more than 99.9%) of the radiation produced by radiation particles incident therein or more than 99.99%) of the charge carriers flow to discrete portions 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.

imaging system

Figure 5 schematically illustrates a perspective view of an imaging system 500 according to an embodiment. In an embodiment, imaging system 500 may include radiation detector 100 and radiation source 510 .

In an embodiment, object 520 may be located between radiation detector 100 and radiation source 510 . For example, object 520 may be a part of a human body (eg, a thigh). In one embodiment, imaging system 500 may be used to scan object 520 .

In one embodiment, the radiation detector 100 and the radiation source 510 may be arranged as shown in FIG. 5 (referred to as a side-incidence arrangement) such that the sensing element plane 104 of the radiation detector 100 intersects the radiation source 510 . Regarding the sensing element plane 104 , the sensing element plane 104 may be a plane that actually intersects all the sensing elements 150 of the radiation detector 100 if all the sensing elements 150 of the radiation detector 100 are coplanar. However, if all sensing elements 150 of radiation detector 100 are not coplanar, sensing element plane 104 may be a best-fit plane (eg, least squares method) for all sensing elements 150 of radiation detector 100 .

If (A) a plane intersects the radiation detector 100 and (B) every point of the radiation detector 100 on that plane at any point during the translation of the radiation detector 100 throughout the translation of the radiation detector 100 If all remain on the plane, the radiation detector 100 is said to translate along the plane.

The source-facing sensing element 150 is the sensing element 150 facing the radiation source 510 . In other words, radiated particles from the radiation source 510 can strike the source-facing sensing element 150 without interference from any other sensing element 150 . In Figure 5, there are seven source-facing sensing elements 150 (top column).

Imaging system operation

In one embodiment, referring to Figure 5, generally, imaging system 500 may operate as follows. Radiation source 510 may send radiation beam 512 to object 520 . Radiation beam 512 may include X-rays. In an example, radiation beam 512 is a fan beam.

In an embodiment, radiation detector 100 and radiation source 510 may be stationary relative to each other during operation of imaging system 500 .

In one embodiment, radiation detector 100 and radiation source 510 may translate along direction 102 as imaging system 500 scans object 520 . In other words, while radiation detector 100 and radiation source 510 translate in direction 102, radiation detector 100 captures multiple images of object 520.

The term "image" in this patent application (including the scope of the claim) is not limited to the spatial distribution of properties (eg intensity) of radiation. For example, the term "image" may also include a spatial distribution of the density of a substance or element.

In one embodiment, direction 102 may be selected such that radiation detector 100 translates along translation plane 106, as shown in FIG. 5 . In one embodiment, the translation plane 106 along which the radiation detector 100 translates may (A) intersect all source-facing sensing elements 150 of the radiation detector 100 , or (B) be all source-facing sensing elements 150 of the radiation detector 100 the best-fitting plane of the sensing element 150 .

Additionally, in one embodiment, the translation plane 106 along which the radiation detector 100 translates may be perpendicular to the straight line 108 that is aligned with the radiation source 510 at one point in time during the translation of the radiation detector 100 (at point X). Intersects the source-facing sensing element 150 .

zigzag scan

6A-6F illustrate the operation of the imaging system 500 when the imaging system 500 performs 6 scans of the object 520 according to an embodiment. Note that FIGS. 6A-6F illustrate top views of radiation detector 100 and object 520 as viewed from radiation source 510 . For simplicity, object 520 is only shown in Figures 6A and 6F (ie, not shown in Figures 6B-6E).

Specifically, in one embodiment, referring to Figure 6A, during a first scan, radiation detector 100 may translate along translation plane 106 from an S position to an A position and along direction 102A. Note that if the imaging system 500 scans an area of the translation plane 106 only once, the area appears (A) brighter, and if the imaging system 500 scans the area at least twice, the area appears (B) brighter. dark.

Next, in an embodiment, referring to FIG. 6B , during a second scan, radiation detector 100 may translate along translation plane 106 from position A to position B and in direction 102B.

Next, in an embodiment, referring to Figure 6C, during the third scan, the radiation detector 100 may translate along the translation plane 106 from the B position to the C position and along direction 102C.

Next, in an embodiment, referring to Figure 6D, during the fourth scan, the radiation detector 100 may translate along the translation plane 106 from the C position to the D position and along direction 102D.

Next, in one embodiment, referring to Figure 6E, during the fifth scan, the radiation detector 100 may translate along the translation plane 106 from the D position to the E position and along direction 102E.

Next, in one embodiment, referring to Figure 6F, during the sixth scan, radiation detector 100 may translate along translation plane 106 from the E position to the F position and along direction 102F.

In one embodiment, the Ox axis and the Oy axis may be defined such that the Ox axis and the Oy axis are on the translation plane 106 and perpendicular to each other, as shown in FIGS. 6A to 6F .

In one embodiment, referring to FIGS. 6A to 6F , the six orthogonal projections of the six directions 102A, 102B, 102C, 102D, 102E, and 102F respectively on the Oy axis may not point to two opposite directions. For example, in FIGS. 6A to 6F , all six orthogonal projections of the six directions 102A, 102B, 102C, 102D, 102E, and 102F on the Oy axis point downward.

In one embodiment, referring to FIGS. 6A to 6F , the six orthogonal projections of the six directions 102A, 102B, 102C, 102D, 102E, and 102F respectively on the Ox axis can point alternately to two opposite directions. For example, in Figure 6A, the orthogonal projection of direction 102A on the Ox axis points to the right. In Figure 6B, the orthogonal projection of direction 102B on the Ox axis points to the left. In Figure 6C, the orthogonal projection of direction 102C on the Ox axis points to the right. In Figure 6D, the orthogonal projection of direction 102D on the Ox axis points to the left. In Figure 6E, the orthogonal projection of direction 102E on the Ox axis points to the right. In Figure 6F, the orthogonal projection of direction 102F on the Ox axis points to the left. In other words, the 6 orthographic projections of the 6 directions 102A, 102B, 102C, 102D, 102E, and 102F on the Ox axis alternately point to the left and right (ie, 2 opposite directions).

In one embodiment, for any two consecutive scans among the six scans, the two corresponding directions 102 may not be parallel to each other. For example, for the first and second scans described above, the two corresponding directions 102A and 102B are not parallel to each other. For another example, for the second and third scans mentioned above, the two corresponding directions 102B and 102C are not parallel to each other.

In one embodiment, referring to FIGS. 6A to 6F , each point of the object 520 may be scanned by at least two of the first, second, third, fourth, fifth and sixth scans (i.e. , scanned by the imaging system 500 at least twice). Assume that object 520 is a human thigh. The data from the at least two scans can then be used to determine the bone density at each point of the person's thigh (referred to as bone densitometry).

Flowchart outlining the operation of the imaging system

Figure 7 shows a flowchart 700 summarizing the operation of imaging system 500, according to an embodiment. In step 710, the operation may include scanning the object with an imaging system that includes a radiation detector and a radiation source that are stationary relative to each other. For example, in the above-described embodiment, referring to Figure 5, imaging system 500 scans object 520, and imaging system 500 includes radiation detector 100 and radiation source 510 that are stationary relative to each other.

Also in step 710, the scanning object includes, for i=1,...,M, sequentially one i value at a time, by (A) along the same translation plane and (B) along the direction (i) Scan (i) is performed by translating the radiation detector, where M is an integer greater than 1. For example, in the above embodiment, referring to FIGS. 5 to 6F , for i = 1, ..., 6, one i value at a time is sequentially moved (A) along the same translation plane 106 and (B) along the same translation plane 106 The scan (i) is performed by translating the radiation detector 100 in direction (i), where M=6. Specifically, for example, referring to Figure 6A, for i=1, scan (1) (ie, the first scan) includes (A) translating the radiation detector 100 along the translation plane 106 and (B) along the direction 102A.

Also in step 710, the Ox axis and the Oy axis are both on the translation plane and perpendicular to each other. Direction (i), i=1, ..., the orthogonal projection of M on the Oy axis does not point in two opposite directions. For example, in the above embodiment, referring to FIGS. 5 to 6F , both the Ox axis and the Oy axis are on the translation plane 106 and are perpendicular to each other. In addition, all orthographic projections of directions 102A, 102B, 102C, 102D, 102E, and 102F on the Oy axis point downward.

Also in step 710, direction (i), the orthogonal projections of i=1,...,M on the Ox axis point alternately into 2 opposite directions. For example, in the above embodiment, referring to FIGS. 5 to 6F , the orthogonal projections of directions 102A, 102B, 102C, 102D, 102E, and 102F on the Ox axis point alternately to the left and right (ie, 2 opposite directions).

Also in step 710, for i=1, ..., (M-1), direction (i) and direction (i+1) are not parallel to each other. For example, in the above embodiment, referring to FIGS. 5 to 6F , for any 2 consecutive scans among 6 scans, the 2 corresponding directions 102 are not parallel to each other. Specifically, for example, direction 102A (FIG. 6A) and direction 102B (FIG. 6B) are not parallel to each other. Similarly, direction 102B (Fig. 6B) and direction 102C (Fig. 6C) are not parallel to each other, and so on.

Also in step 710, each point of the object is scanned by scanning (i), at least two scans of i=1,...,M. For example, in the above-described embodiment, referring to FIG. 6F , each point of the object 520 is scanned through at least two of the first, second, third, fourth, fifth and sixth scans.

Other embodiments

Scan twice exactly

In the above embodiment, referring to FIGS. 5 to 6F , each point of the object 520 is scanned by the imaging system 500 at least twice. In one embodiment, each point of object 520 is scanned by imaging system 500 no more than twice. In other words, each point of object 520 is scanned exactly twice by imaging system 500, as shown in Figures 6A-6F.

Alternating energy ranges for zigzag scans

In one embodiment, referring to FIG. 6A , during a first scan, radiation source 510 may send a first radiation beam of a first energy range to object 520 (as part of radiation beam 512 ). In other words, each radiation particle of the first radiation beam has an energy within the first energy range. The first radiation beam may be used by radiation detector 100 to perform a first scan.

Similarly, in one embodiment, referring to FIG. 6C , during a third scan, radiation source 510 may send a third radiation beam of a first energy range to object 520 (as part of radiation beam 512 ). The third radiation beam may be used by the radiation detector 100 to perform the third scan.

Similarly, in one embodiment, referring to FIG. 6E , during a fifth scan, radiation source 510 may send a fifth radiation beam of a first energy range to object 520 (as part of radiation beam 512 ). The fifth radiation beam may be used by the radiation detector 100 to perform a fifth scan.

In one embodiment, referring to FIG. 6B , during the second scan, radiation source 510 may send a second radiation beam of a second energy range to object 520 (as part of radiation beam 512 ). In other words, each radiation particle of the second radiation beam has an energy within the second energy range. The second radiation beam may be used by the radiation detector 100 to perform a second scan.

Similarly, in one embodiment, referring to FIG. 6D , during the fourth scan, radiation source 510 may send a fourth radiation beam of a second energy range to object 520 (as part of radiation beam 512 ). The fourth radiation beam may be used by radiation detector 100 to perform a fourth scan.

Similarly, in one embodiment, referring to FIG. 6F , during the sixth scan, radiation source 510 may send a sixth radiation beam of the second energy range to object 520 (as part of radiation beam 512 ). The sixth radiation beam may be used by radiation detector 100 to perform a sixth scan.

In one embodiment, the first energy range and the second energy range may be different. In an embodiment, the first energy range and the second energy range may not overlap.

Bidirectional counter for each sensing element of the radiation detector

In one embodiment, referring to FIGS. 1-5 , the electronics layer 120 of the radiation detector 100 may include a counter (not shown) for each sensing element 150 of the radiation detector 100 .

In an embodiment, if radiated particles in the third energy range impact each sensing element 150, the counter of each sensing element may count by 1 (ie, its count is increased by 1); if the When radiated particles of four energy ranges impact each sensing element 150, the counter of each sensing element can count by 1 (ie, its count is decremented by 1), and the third energy range and the fourth energy range No overlap. Please note that the counter of each sensing element 150 of the radiation detector 100 is a bidirectional counter.

Two counters per sensing element

In one embodiment, referring to FIGS. 1 to 5 , the electronic device layer 120 of the radiation detector 100 may include a first counter (not shown) and a second counter (not shown) of each sensing element 150 of the radiation detector 100 . Shows). In one embodiment, the first counter of each sensing element 150 may record the number of radiation particles in the fifth energy range that hit each sensing element 150; The second counter may record the number of radiation particles in the sixth energy range that hit each sensing element 150, and the fifth energy range does not overlap with the sixth energy range.

The translation distance on the Ox axis is the same

In one embodiment, referring to Figures 6A to 6F, (A) the translation distance (ie, distance 102Ax) of the first scan (Figure 6A) measured in the direction parallel to the Ox axis, (B) in the direction parallel to the Ox axis Translation distance of the second scan (Fig. 6B) measured in the direction of the Ox axis (not shown), (C) of the third scan (Fig. 6C) measured in the direction parallel to the Ox axis (not shown) Translation distance, (D) Translation distance of the fourth scan (Fig. 6D) measured in a direction parallel to the Ox axis (not shown), (E) measured in a direction parallel to the Ox axis (not shown) The translation distance of the fifth scan (Figure 6E), and (F) the translation distance of the sixth scan (Figure 6F) measured in a direction parallel to the Ox axis (not shown) can be the same. In other words, the six horizontal translation distances of the six scans are all the same. Note that for simplicity, only the first horizontal translation distance (ie, distance 102Ax) is shown in Figure 6A (ie, the other 5 horizontal translation distances are not shown).

The sum of 2 consecutive vertical translation distances

In one embodiment, referring to FIG. 6B , (A) the translation distance of the first scan in the direction parallel to the Oy axis (ie, the distance 102Ay) and (B) the second scan in the direction parallel to the Oy axis. The sum of the scanning translation distances (ie, the distance 102By) may not exceed the size of the radiation detector 100 in a direction parallel to the Oy axis (ie, the size 100y).

In summary, the above embodiments can be expressed as follows: (A) the translation distance of scanning (i) in the direction parallel to the Oy axis and (B) the scanning (i+1) in the direction parallel to the Oy axis The sum of the translation distances may not exceed the size of the radiation detector 100 in the direction parallel to the Oy axis (i=1, 2, 3, 4, 5).

Special case—horizontal translation

In one embodiment, referring to FIGS. 6A to 6F , for any two consecutive scans, one of the two corresponding translation directions 102 may be parallel to the Ox axis. For example, referring to Figures 6A and 6B, one of the 2 directions 102A and 102B may be parallel to the Ox axis. Specifically, for example, direction 102A may point southeast, and direction 102B may point due west (ie, parallel to the Ox axis). In this particular example, referring to Figure 6B, distance 102Ay is equal to dimension 100y and distance 100By is zero.

More information about translation direction

In one embodiment, referring to FIGS. 6A to 6F and step 710 of FIG. 7 , for i=1,...,(M-2), the direction (i) and the direction (i+2) may be mutually exclusive. parallel. For example, direction 102A and direction 102C are parallel to each other. For another example, direction 102B and direction 102D are parallel to each other.

Although 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 purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the appended claims.

2-2: Line 100: Radiation detector 100By, 102Ax, 102Ay: distance 100y: size 102, 102A, 102B, 102C, 102D, 102E, 102F: direction 104: Sensing element plane 106:Translation plane 108: straight line 110: Radiation absorbing layer 111: First doped region 112:Eigen region 113: Second doping region 114: Discrete area 119A, 119B: Electrical contacts 120: Electronic device layer 121: Electronic systems 130: Filling material 131:Through hole 150: pixels 500: Imaging system 510: Radiation source 512: Radiation Beam 520:Object 700:Flowchart 710: Steps A, B, C, D, E, F, S: Location Ox, Oy: axis X: point

Figure 1 schematically shows a radiation detector according to an embodiment. Figure 2 schematically shows a simplified cross-sectional view of a radiation detector according to an embodiment. Figure 3 schematically shows a detailed cross-sectional view of a radiation detector according to an embodiment. Figure 4 schematically shows a detailed cross-sectional view of a radiation detector according to an alternative embodiment. Figure 5 schematically shows a perspective view of an imaging system according to an embodiment. 6A-6F illustrate the operation of an imaging system according to an embodiment. Figure 7 shows a flowchart summarizing the operation of an imaging system, according to an embodiment.

100: Radiation detector

102: Direction

104: Sensing element plane

106:Translation plane

108: straight line

150: pixels

500: Imaging system

510: Radiation source

512: Radiation Beam

520:Object

X: point

Claims (26)

A scanning method that includes: An object is scanned with an imaging system including a radiation detector and a radiation source stationary relative to each other, wherein the scanned object includes: For i=1,...,M, scan (i) is performed sequentially one value at a time by translating the radiation detector (A) along the same translation plane and (B) in direction (i) , where M is an integer greater than 1, Wherein, the Ox axis and the Oy axis are both on the translation plane and perpendicular to each other, Wherein, the orthogonal projection of the direction (i), i=1,...,M on the Oy axis does not point to two opposite directions, Wherein, in the direction (i), the orthogonal projections of i=1,...,M on the Ox axis point alternately in two opposite directions, Wherein, for i=1,...,(M-1), the direction (i) and the direction (i+1) are not parallel to each other, and Wherein, each point of the object is scanned by at least two of the scans (i), i=1,...,M. The scanning method as claimed in claim 1, wherein for i=1,..., (M-2), the direction (i) and the direction (i+2) are parallel to each other. The scanning method as described in claim 1, wherein each point is scanned by no more than 2 scans in (i), i=1,...,M. The scanning method of claim 1, wherein the translation plane either (A) intersects all source-facing sensing elements of the radiation detector, or (B) is all source-facing sensing elements of the radiation detector The best-fitting plane of the sensing element. The scanning method according to claim 4, wherein at the time point during the scan (i), i=1,...,M, the translation plane is perpendicular to the radiation source A straight line intersecting the source-facing sensing element of the radiation detector. The scanning method according to claim 1, wherein the sensing element plane of the radiation detector intersects the radiation source. Scanning method as described in request 1, wherein for each odd value of i, said scanning (i) includes sending a radiation beam (i) of the same first energy range to said object with said radiation source, wherein, for each even value of i, said scanning (i) includes sending a radiation beam (i) of the same second energy range to said object with said radiation source, Wherein, the first energy range and the second energy range are different. The scanning method of claim 7, wherein the first energy range and the second energy range do not overlap. Scanning method as described in request 1, wherein, for each value of i, the scan (i) includes incrementing a counter of the radiation detector by one in response to a third energy range of radiation particles impacting the radiation detector, and in response to a fourth Radiation particles in the energy range impact the radiation detector and the counter is used to count down by 1, Wherein, the third energy range and the fourth energy range do not overlap. The scanning method as described in claim 1, wherein for each value of i, the scanning (i) includes: recording, with a first counter of the radiation detector, a number of radiation particles of a fifth energy range that strike a sensing element of the radiation detector; and recording, with a second counter of the radiation detector, a number of radiation particles of a sixth energy range striking the sensing element, and Among them, the fifth energy range and the sixth energy range do not overlap. The scanning method as described in claim 1, wherein in the scan (i), all M translation distances of i=1,...,M respectively measured in the direction parallel to the Ox axis All the same. The scanning method as claimed in claim 11, wherein for i=1,..., (M-1), (A) the scanning (i) in a direction parallel to the Oy axis The sum of the translation distances (B) of the scan (i+1) in the direction parallel to the Oy axis does not exceed the size of the radiation detector in the direction parallel to the Oy axis . The scanning method as claimed in claim 12, wherein for i=1, ..., (M-1), the direction (i) and one of the directions (i+1) are parallel on the Ox axis. A scanning device including an imaging system including a radiation detector and a radiation source stationary relative to each other, wherein the imaging system is configured to scan the object, Wherein, the scanning of the object by the imaging system includes: For i=1,...,M, scan (i) is performed sequentially one value at a time by translating the radiation detector (A) along the same translation plane and (B) in direction (i) , where M is an integer greater than 1, Wherein, the Ox axis and the Oy axis are both on the translation plane and perpendicular to each other, Wherein, the orthogonal projection of the direction (i), i=1,...,M on the Oy axis does not point to two opposite directions, Wherein, in the direction (i), the orthogonal projections of i=1,...,M on the Ox axis point alternately in two opposite directions, Wherein, for i=1,...,(M-1), the direction (i) and the direction (i+1) are not parallel to each other, and Wherein, each point of the object is scanned by at least two of the scans (i), i=1,...,M. The scanning device according to claim 14, wherein for i=1,..., (M-2), the direction (i) and the direction (i+2) are parallel to each other. The scanning device as claimed in claim 14, wherein each point is scanned by no more than 2 scans in (i), i=1,...,M. The scanning device of claim 14, wherein the translation plane either (A) intersects all source-facing sensing elements of the radiation detector, or (B) is all source-facing sensing elements of the radiation detector The best-fitting plane of the sensing element. The scanning device according to claim 17, wherein at the time point during the scan (i), i=1,...,M, the translation plane is perpendicular to the radiation source. A straight line intersecting the source-facing sensing element of the radiation detector. The scanning device of claim 14, wherein the sensing element plane of the radiation detector intersects the radiation source. A scanning device as claimed in claim 14, wherein for each odd value of i, said scanning (i) includes sending a radiation beam (i) of the same first energy range to said object with said radiation source, wherein, for each even value of i, said scanning (i) includes sending a radiation beam (i) of the same second energy range to said object with said radiation source, Wherein, the first energy range and the second energy range are different. The scanning device of claim 20, wherein the first energy range and the second energy range do not overlap. A scanning device as claimed in claim 14, wherein, for each value of i, the scan (i) includes incrementing a counter of the radiation detector by one in response to a third energy range of radiation particles impacting the radiation detector, and in response to a fourth Radiation particles in the energy range impact the radiation detector and the counter is used to count down by 1, Wherein, the third energy range and the fourth energy range do not overlap. The scanning device of claim 14, wherein for each value of i, the scanning (i) includes: recording, with a first counter of the radiation detector, a number of radiation particles of a fifth energy range that strike a sensing element of the radiation detector; and recording, with a second counter of the radiation detector, a number of radiation particles of a sixth energy range striking the sensing element, and Among them, the fifth energy range and the sixth energy range do not overlap. The scanning device according to claim 14, wherein in the scan (i), all M translation distances of i=1,...,M respectively measured in the direction parallel to the Ox axis All the same. The scanning device according to claim 24, wherein for i=1,..., (M-1), (A) the scanning (i) in a direction parallel to the Oy axis The sum of the translation distances (B) of the scan (i+1) in the direction parallel to the Oy axis does not exceed the size of the radiation detector in the direction parallel to the Oy axis . The scanning device according to claim 25, wherein for i=1, ..., (M-1), the direction (i) and one of the directions (i+1) are parallel on the Ox axis.

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