Radiation detector and radiation imaging apparatus including the radiation detector

Abstract

An object of the present invention is to reduce a processing load and power consumption, and to provide intensity information and energy information. A radiation detector (100) is configured by laminating a radiation detection element (1) and a plurality of readout circuits (8a, 8b) on top of each other. In the radiation detection element (1), a plurality of pixels (7d) that generate charges corresponding to the energy of X-rays that have passed through a subject are two-dimensionally arranged. The plurality of readout circuits (8a, 8b) output intensity signals of the transmitted X-rays based on the charges generated by each of the plurality of pixels (7d). A part of the readout circuits (8a) that are arranged at intervals among the plurality of readout circuits (8a, 8b) generates a spectrum signal related to the spectrum of the transmitted X-rays based on the charges, and outputs the spectrum signal.

Description

Technical Field

[0001] The present invention describes a radiation detector and a radiation imaging apparatus including the radiation detector. Background Art

[0002] As an existing imaging apparatus using X-rays, as described in Patent Document 1 below, an X-ray CT (Computed Tomography) apparatus is known. This X-ray CT apparatus has a function of reconstructing a CT image capable of material discrimination by detecting X-rays that have passed through a subject at two or more energy levels (hereinafter, referred to as spectral CT). According to spectral CT, not only can a distribution of linear attenuation coefficients, that is, a CT image, be obtained, but also a distribution of physical property data such as an effective atomic number can be obtained.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2020-99667 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] An imaging apparatus having the above-described spectral CT function can generate a cross-sectional image in which a distribution of physical property data is mapped to colors and overlaid on a normal CT image. In such an imaging apparatus, in the case of adopting a structure including a radiation detector having a plurality of pixels, it is necessary to obtain intensity information for reconstructing a CT image and intensity information at two or more energy levels (hereinafter, also referred to as energy information) from all the pixels. As a result, in existing imaging apparatuses, there is a tendency for the processing load and power consumption to increase.

[0008] The present invention describes a radiation detector and a radiation imaging apparatus including the radiation detector that can reduce the processing load and power consumption and can provide intensity information and energy information.

[0009] Means for Solving the Problems

[0010] A radiation detector according to one aspect of the present invention is configured by laminating a charge generation unit and a plurality of readout circuits. The charge generation unit two-dimensionally arranges a plurality of charge generation regions that generate charges corresponding to the energy or the number of particles of radiation that has passed through a subject. The plurality of readout circuits output radiation intensity signals based on the charges generated by each of the plurality of charge generation regions. A part of the readout circuits that are arranged at intervals among the plurality of readout circuits generates a spectral signal related to the spectrum of the radiation based on the charge and outputs the spectral signal.

[0011] In this radiation detector, charges corresponding to the energy of incident radiation or the number of particles are generated in a plurality of charge generation regions of a charge generation unit, and intensity information of the radiation based on the charges is output in a readout circuit corresponding to each charge generation region. At the same time, in a part of the readout circuits arranged at intervals among the plurality of readout circuits, a spectrum signal related to the spectrum of the radiation based on the charges is generated and output. As a result, the resolution of the intensity information of the image of the subject can be maintained, and the energy information of each charge generation region output from the radiation detector can be reduced. As a result, the resolution of the output image of the subject can be maintained, and the processing load and power consumption can be reduced.

[0012] In one mode, a part of the readout circuits may also generate a spectrum signal based on the charges generated in the charge generation region arranged corresponding to the readout circuit. In this case, a spectrum signal related to the spectrum of the radiation incident on each charge generation region is generated and output based on the charges generated in a part of the charge generation regions arranged at intervals among the plurality of charge generation regions. As a result, the processing load and power consumption can be reduced, and the intensity information and the energy information can be output.

[0013] In one mode, a part of the readout circuits may also generate a spectrum signal based on the charges generated in the charge generation region arranged corresponding to the readout circuit and the charges generated in the charge generation regions within a predetermined range of the charge generation region. In this case, a spectrum signal summarizing the spectra of the radiation incident on each charge generation region within the predetermined range is generated and output based on the charges generated in a plurality of charge generation regions included within the predetermined range among the plurality of charge generation regions. As a result, the processing load and power consumption can be reduced, and the intensity information and the energy information can be output.

[0014] In one mode, a part of the readout circuits may also generate data representing a plurality of combinations of the energy of the radiation and the intensity values corresponding to the energy as the spectrum signal. According to this configuration, the energy information for obtaining the distribution of physical property data can be effectively output only from a part of the readout circuits arranged at intervals. As a result, the processing load and power consumption can be reduced, and the intensity information and the energy information can be output.

[0015] A radiation imaging apparatus according to another aspect of the present invention includes: the above-described radiation detector; and a processor that generates an image based on the intensity signal and the spectrum signal output from the radiation detector. According to this radiation imaging apparatus, the processing load and power consumption can be reduced, and the generation of an image based on the intensity information and the energy information can be achieved.

[0016] In other modes, the processor may also generate information representing an image of a subject as high-resolution luminance information based on intensity signals output from a plurality of readout circuits, generate information representing the distribution of physical properties of the subject as low-resolution color information based on spectral signals output from a part of the readout circuits, and generate a color image of the subject by combining the luminance information and the color information. According to this configuration, a detailed image of the subject can be effectively generated in a state where the distribution of physical properties can be visually recognized.

[0017] In other modes, the processor may also have a function of reconstructing a CT image based on intensity signals and spectral signals output from a radiation detector. In such a configuration, spectral CT with reduced processing load and power consumption can be achieved.

[0018] Advantages of the Invention

[0019] The radiation detector and the radiation imaging apparatus of the present invention can reduce the processing load and power consumption, and can provide intensity information and energy information. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a perspective view showing the radiation detector 100 of the embodiment.

[0021] Figure 2 is Figure 1 a cross-sectional view of the radiation detection element 1.

[0022] Figure 3 is a block diagram showing the configuration of the radiation imaging apparatus 200 of the embodiment.

[0023] Figure 4 is showing Figure 3 an example of the functional configuration of the processor 9.

[0024] Figure 5 is a diagram showing an example of an image processed by the processor 9.

[0025] Figure 6 is a diagram showing an example of an image processed by the processor 9.

[0026] Figure 7 is a cross-sectional view of the radiation detection element 1 of the modified example. DETAILED DESCRIPTION OF THE INVENTION

[0027] Hereinafter, the radiation detector and the radiation imaging apparatus of the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same reference numerals are assigned to the same elements, and redundant description is omitted.

[0028] Figure 1The radiation detector 100 of the illustrated embodiment is a device for obtaining a sectional image based on radiation that has passed through a subject. The radiation may be, for example, γ-rays, X-rays, α-rays, β-rays, etc., but in the present embodiment, it is X-rays. The radiation detector 100 includes a radiation detection element 1, a processing unit 2, and a control unit 3.

[0029] The radiation detection element 1 has a rectangular plate-shaped readout circuit substrate 8 and a rectangular plate-shaped detection element substrate (charge generation unit) 7 laminated on the readout circuit substrate 8. The detection element substrate 7 is a substrate made of a material that generates charges corresponding to the energy of X-rays that have passed through a subject and entered. However, when a particle beam is detected as radiation, the detection element substrate 7 is made of a material that generates charges corresponding to the number of radiation particles. The detection element substrate 7 has a plurality of pixels, and electron-hole pairs (charge pairs) are generated by X-rays incident on each pixel. As this detection element substrate 7, for example, a Cd(Zn)Te charge generator, Si charge generator, Ge charge generator, GaAs charge generator, GaN charge generator, TlBr charge generator, etc. can also be used. In addition, as the detection element substrate 7, a device having a scintillator and a photodetector in each pixel can also be used. The scintillator converts X-rays into light. The photodetector converts the light generated by the scintillator into charges. The readout circuit substrate 8 is a substrate in which a circuit group is built, and the circuit group generates and outputs a signal based on the charges generated in each pixel by the detection element substrate 7.

[0030] Figure 2 is a cross-sectional view of the radiation detection element 1. As shown in the figure, the detection element substrate 7 includes: a detection element 7a made of a compound semiconductor such as CdTe in a rectangular flat plate shape; a surface electrode 7b and a plurality of bump electrodes 7c. The surface electrode 7b is formed on the entire surface of the radiation incident side of the detection element 7a. Protrusion-shaped electrodes, that is, bump electrodes 7c, are formed two-dimensionally on the back surface of the detection element 7a. In the detection element substrate 7 having this structure, pixels (charge generation regions) 7d are formed in each of a plurality of regions of the detection element 7a that face the bump electrodes 7c. When using the radiation detector 100, a positive bias voltage is applied to the surface electrode 7b from the outside. As a result, charges corresponding to the energy of X-rays incident on each pixel 7d of the detection element 7a are generated as current signals, and the current signals are taken out from the bump electrodes 7c corresponding to each pixel 7d of the detection element 7a to the readout circuit substrate 8. For example, the bump electrodes 7c are two-dimensionally arranged in a 96×96 manner on the back surface of the detection element 7a. In this structure, the radiation detection element 1 has pixels 7d two-dimensionally arranged in a 96×96 manner.

[0031] The readout circuit board 8 is disposed on the back side of the detection element substrate 7 in a state of being joined to the bump electrodes 7c. In this readout circuit board 8, a plurality of readout circuits 8a and 8b are built in at positions opposed to a plurality of pixels 7d of the detection element substrate 7. Each of the plurality of readout circuits 8a and 8b is electrically connected to the plurality of pixels 7d of the detection element substrate 7 via the bump electrodes 7c. These plurality of readout circuits 8a and 8b are provided at positions opposed to the plurality of pixels 7d, the readout circuit 8a is provided at a position opposed to the pixels 7d that are arranged at intervals of two pixels in the two-dimensional arrangement direction of the plurality of pixels 7d, and the readout circuit 8b is provided at a position opposed to the pixels 7d other than the pixels 7d arranged at intervals. That is, the readout circuit 8a is a part of the plurality of readout circuits 8a and 8b that are opposed to all the pixels 7d of the detection element substrate 7 and are arranged at intervals. Further, in the present embodiment, the readout circuit 8a is provided for each pixel 7d arranged at intervals of two pixels, but the degree of the interval arrangement can be appropriately changed to intervals of seven pixels, intervals of fifteen pixels, intervals of thirty-one pixels, etc.

[0032] The readout circuit 8b processes the charges generated by the respective pixels 7d of the detection element substrate 7. Specifically, the readout circuit 8b accumulates the current signal for a certain constant period based on the current signal output from the pixel 7d opposed to the readout circuit 8b to generate an X-ray intensity signal. Then, the readout circuit 8b outputs the intensity signal of each pixel 7d to a processing unit 2 described later. The intensity signal of each pixel 7d output by the readout circuit 8b is a signal indicating the intensity of the X-ray incident on each pixel 7d.

[0033] The readout circuit 8a processes the charges generated by the pixels 7d arranged at intervals among all the pixels 7d of the detection element substrate 7. That is, the readout circuit 8a includes a multi-channel analyzer (MCA), counts the current signal output from the pixel 7d corresponding to the readout circuit 8a as a pulse signal, detects the height of the pulse signal as the energy of the X-ray photon, and records the count value (intensity value) of each energy. Then, the readout circuit 8a generates data of a plurality of combinations of the value indicating the energy of the X-ray photon and the count value (intensity value) of the energy as a spectrum signal indicating the spectrum of the incident X-ray. Then, the readout circuit 8a outputs the spectrum signal of each pixel 7d to a processing unit 2 described later. Among them, in addition to the function of generating and outputting the spectrum signal of the corresponding each pixel 7d, the readout circuit 8a may also have a function of generating and outputting the intensity signal of each pixel 7d in the same manner as the readout circuit 8b. Further, since the readout circuit 8a has a function of generating a spectrum signal, the circuit scale occupied in the readout circuit board 8 is larger than the circuit scale occupied by the readout circuit 8b.

[0034] Return Figure 1 The processing unit 2 is connected to each of the readout circuits 8a and 8b in the readout circuit board 8 via the wiring unit 4. The processing unit 2 receives the intensity signal and the spectral signal of each pixel from each of the readout circuits 8a and 8b. For example, the processing unit 2 sequentially receives the intensity signal of each pixel from the readout circuit 8b, receives the spectral signal of each pixel arranged at intervals from the readout circuit 8a, and outputs the received intensity signal and spectral signal of each pixel to the outside.

[0035] The control unit 3 is connected to each of the readout circuits 8a and 8b in the readout circuit board 8 via the wiring unit 6. The control unit 3 supplies control signals for controlling the charge detection timing, the intensity signal and spectral signal generation timing, and their output timing to the plurality of readout circuits 8a and 8b. For example, the control unit 3 supplies a control signal to set the charge detection timing in synchronization with the irradiation timing of external X-rays, and then supplies a control signal to sequentially output the intensity signal and the spectral signal from each pixel 7d of the detection element substrate 7.

[0036] Figure 3 is a block diagram showing the structure of the radiation imaging apparatus 200 according to the embodiment. The radiation imaging apparatus 200 includes: the above-described radiation detector 100 and a processor 9. The processor 9 processes the intensity signal of each pixel and the spectral signal of each pixel output from the radiation detector 100, and thereby generates and outputs a cross-sectional image of the subject. The processor 9 receives the intensity signal and the spectral signal from the processing unit 2 of the radiation detector 100 via a wired communication or wireless communication network.

[0037] The processor 9 includes: a CPU (Central Processing Unit), which executes an operating system, application programs, etc.; a main storage device, which is composed of a ROM (Read Only Memory) and a RAM (Random Access Memory); an auxiliary storage device, which is composed of a hard disk, a flash memory, etc.; a communication control device, which is composed of a network card or a wireless communication module; an input device, which is a keyboard, a mouse, a touch panel, etc.; and an output device, which is a monitor, a touch panel display, etc. Each functional element of the processor 9 is realized by reading a predetermined program into the CPU or the main storage device and causing the CPU to execute the program. The CPU causes the communication control device, the input device, or the output device to operate according to the program, and reads and writes data in the main storage device or the auxiliary storage device. Data or databases required for processing are stored in the main storage device or the auxiliary storage device.

[0038] Figure 4FIG. 0 is a block diagram showing an example of the functional structure of processor 9. Processor 9 includes an intensity image generation unit 11, an energy image generation unit 12, a CT image generation unit 13, and an image overlapping unit 14 as functional elements.

[0039] The intensity image generation unit 11 generates a high-resolution intensity image representing the intensity distribution of the X-ray transmission image of the subject using the intensity signal of each pixel and the spectral signal of each pixel output from the radiation detector 100. That is, the intensity image generation unit 11 transforms the intensity signal and spectral signal of each image into the pixel value of each pixel of the intensity image. Among them, when only the spectral signal of the pixel corresponding to the readout circuit 8a is acquired, the intensity image generation unit 11 integrates the intensity values of each energy among the multiple energies over all energies based on this spectral signal and transforms it into the intensity value of the corresponding pixel.

[0040] The energy image generation unit 12 uses the spectral signals of the pixels arranged at intervals output from the radiation detector 100 to generate a low-resolution energy image representing the intensity distribution of the X-ray transmission image of a specified energy band of the subject for multiple energy bands. In the present embodiment, since the CT image generation unit 13 acquires two types of energy information by the dual energy computed tomography (DECT) method, energy images of two energy bands (for example, energy bands of 25 keV and 65 keV) are generated. Among them, the energy image generation unit 12 integrates the intensity values of each energy band among the two energy bands based on the spectral signal of the pixel corresponding to the readout circuit 8a and transforms it into the intensity value of the pixel of the energy image.

[0041] The CT image generation unit 13 acquires the high-resolution intensity image generated by the intensity image generation unit 11 for various irradiation directions of the X-ray with respect to the subject, analyzes the intensity images in various irradiation directions, and generates a CT image representing the distribution of the high-resolution linear attenuation coefficient in a specified cross-section of the subject. At this time, the CT image generation unit 13 can adopt methods such as two-dimensional Fourier transform method, filtered back-projection method, iterative reconstruction method, etc. as the image reconstruction method used in the generation of the CT image.

[0042] In addition, the CT image generation unit 13 acquires the low-resolution energy images of multiple energy bands generated by the energy image generation unit 12 for various irradiation directions, analyzes these low-resolution energy images, and generates low-resolution CT images of multiple energy bands in a specified cross-section of the subject. At this time, the CT image generation unit 13 can adopt the above methods as the image reconstruction method used in the generation of the CT image.

[0043] In addition, the CT image generation unit 13 generates a physical property distribution image representing the distribution of physical properties in the tomographic plane of the subject, based on low-resolution CT images of multiple energy bands. For example, in the case of adopting the dual-energy CT method, the CT image generation unit 13 uses the following formula representing the relationship between the linear attenuation coefficient μ, the energy value E, the electron density ρ, the atomic number Z, the photoelectric absorption attenuation coefficient F, and the scattering attenuation coefficient G; uses the relationship of μ = ρ[Z 4 F(E, Z) + G(E, Z)], and calculates the effective atomic number Z and the electron density ρ for each pixel based on the linear attenuation coefficients of the CT images of two energy bands. Among them, the photoelectric absorption attenuation coefficient F and the scattering attenuation coefficient G are known functions (for example, a mapping table) with the energy value E and the atomic number Z as independent variables, and are pre-stored in the processor 9. Then, the CT image generation unit 13 generates a physical property distribution image representing the distribution of the effective atomic number Z or the electron density ρ of low resolution by allocating the calculated effective atomic number Z or electron density ρ for each pixel.

[0044] The image overlapping unit 14 sets each pixel value of the high-resolution CT image generated by the CT image generation unit 13 as the luminance information of the output image, and sets each pixel value of the low-resolution physical property distribution image generated by the CT image generation unit 13 as the color information of the output image, and generates a color image, that is, the output image, by combining the luminance information and the color information for each pixel. Thus, the image overlapping unit 14 can visually output the distribution of the linear attenuation coefficient in the specified tomographic plane of the subject and the distribution of the physical property values in the specified tomographic plane at the same time. In such an output image, by overlapping a low-resolution color grid (lines or dots) on a high-resolution black-and-white image, an observer can be made to recognize it as a high-resolution color image through an optical illusion.

[0045] In Figure 5 and Figure 6 shows an example of an image after the processor 9 processes a model simulating bones and blood vessels as the subject. In Figure 5 the image G1 represents a low-resolution CT image of the 25 keV energy band, the image G2 represents a low-resolution CT image of the 65 keV energy band, the image G3 represents a physical property distribution image of the effective atomic number generated based on the image G1 and the image G2, and the image G4 represents a physical property distribution image of the electron density generated based on the image G1 and the image G2. In Figure 6In this case, the image G5 represents a physical property distribution image of the electron density when the spectral signals are arranged at intervals of every seven pixels, the image G6 represents an output image in which the image G5 is superimposed, the image G7 represents a physical property distribution image of the electron density when the spectral signals are arranged at intervals of every fifteen pixels, the image G8 represents an output image in which the image G7 is superimposed, the image G9 represents a physical property distribution image of the electron density when the spectral signals are arranged at intervals of every thirty-one pixels, and the image G10 represents an output image in which the image G9 is superimposed. From these results, it can be seen that when the degree of the spaced arrangement is every seven pixels and every fifteen pixels, the distribution of the electron density is clearly shown in the output image, so that the physical property distribution can be visually recognized.

[0046] In the radiation detector 100 described above, charges corresponding to the energy of the incident X-rays are generated in the plurality of pixels 7d of the detection element substrate 7, and intensity signals representing the intensity distribution of the transmitted X-rays based on the charges are output in the readout circuits 8a and 8b corresponding to the respective pixels 7d. At the same time, in a part of the readout circuits 8a among the plurality of readout circuits 8a and 8b that are spaced apart, spectral signals related to the spectrum of the transmitted X-rays based on the charges are generated and output. As a result, it is possible to maintain the resolution of the intensity information of the transmitted X-ray image of the subject, and to reduce the energy information of each pixel 7d output by the radiation detector 100. As a result, it is possible to maintain the resolution of the output image of the subject and to reduce the processing load and power consumption.

[0047] In the present embodiment, a part of the readout circuits 8a generate spectral signals based on the charges generated in the pixels 7d arranged corresponding to the readout circuits 8a. In this case, spectral signals related to the spectrum of the transmitted X-rays incident on each pixel 7d are generated and output based on the charges generated in a part of the pixels 7d among the plurality of pixels 7d that are spaced apart. As a result, it is possible to reduce the processing load and power consumption, and to output intensity information and energy information.

[0048] In the present embodiment, a part of the readout circuits 8a generate data representing a plurality of combinations of the energy of the transmitted X-rays and the intensity values corresponding to the energy as spectral signals. According to this configuration, since it is possible to effectively output only from a part of the readout circuits 8a that are spaced apart the energy information for obtaining the distribution of the physical property data. As a result, it is possible to reduce the processing load and power consumption, and to output intensity information and energy information.

[0049] Since the radiation imaging apparatus 200 according to the present embodiment includes the above-described radiation detector 100, it is possible to reduce the processing load and power consumption, and to generate an image based on the intensity information and the energy information.

[0050] In particular, the processor 9 included in the radiographic imaging apparatus 200 generates information representing an X-ray transmission image of a subject as high-resolution luminance information based on intensity signals output from a plurality of readout circuits 8a and 8b, generates information representing the distribution of physical properties of the subject as low-resolution color information based on spectral signals output from a part of the readout circuits 8a, and generates a color image of the subject by combining the luminance information and the color information. According to this configuration, it is possible to effectively generate a detailed CT image of the subject in a state where the distribution of physical properties can be visually recognized simultaneously.

[0051] In addition, in the present embodiment, the processor 9 may also have a function of reconstructing a CT image based on the intensity signal and the spectral signal output from the radiation detector 100. In such a configuration, spectral CT with reduced processing load and power consumption can be achieved.

[0052] The radiation detector of the present invention is not limited to the above-described embodiment. The radiation detector of the present invention can be variously modified without departing from the scope of the claims.

[0053] The number of pixels or the degree of spaced arrangement in the radiation detector 100 in the above-described embodiment is an example, and various changes can be made.

[0054] In addition, the data output from the radiation detector 100 is not limited to the intensity signal and the spectral signal based on the charge corresponding to the energy of the radiation, and may also be a signal based on the charge corresponding to the number of radiation particles incident on each pixel of the radiation detector 100.

[0055] The structure of the readout circuit board 8 of the radiation detector 100 in the above-described embodiment can also be changed to Figure 7 the structure shown. In Figure 7 the illustrated modification example, a plurality of readout circuits 8c connected to the readout circuits 8a within a specified range adjacent in a two-dimensional direction are further provided in the readout circuit board 8. The readout circuit 8c generates and outputs one spectral signal (performs a combining process) by aggregating the spectral signals based on the charges generated by the pixels 7d disposed opposite to one readout circuit 8a and the spectral signals generated by one or more readout circuits 8a disposed opposite to the pixels 7d within the specified range of the pixel 7d. For example, when aggregating a plurality of spectral signals into one signal, the readout circuit 8c uses a method of summing or averaging the intensity values for each energy.

[0056] According to this modification example, based on the charges generated in a plurality of pixels 7d included within a specified range, a spectral signal is generated and output, which summarizes the spectra of the X-rays transmitted through each pixel 7d incident on the specified range. Thereby, the processing load and power consumption can be reduced, and intensity information and energy information can be output.

[0057] In addition, in the above modification example, all the readout circuits corresponding to the pixels 7d of the radiation detection element 1 may have the function of generating a spectral signal, and a plurality of readout circuits 8c may perform a merging process on the spectral signals output from the readout circuits within the specified range as an object.

[0058] Explanation of reference numerals:

[0059] 100: Radiation detector

[0060] 200: Radiation imaging device

[0061] 7: Detection element substrate (charge generation section)

[0062] 7d: Pixel (charge generation region)

[0063] 8: Readout circuit substrate

[0064] 8a, 8b, 8c: Readout circuit

[0065] 9: Processor

Claims

1. A radiation detector, wherein, the radiation detector is formed by laminating a charge generation section and a plurality of readout circuits; the charge generation section two-dimensionally arranges a plurality of charge generation regions that generate charges corresponding to the energy of radiation that has passed through the subject or the number of particles; the plurality of readout circuits include: a plurality of readout circuits that generate spectral signals related to the spectrum of the radiation based on the charges generated by each of a part of the charge generation regions that are arranged at intervals of a plurality of the charge generation regions among the plurality of charge generation regions, and output the spectral signals; and a plurality of readout circuits that output intensity signals of the radiation based on the charges generated by each of another part of the charge generation regions among the plurality of charge generation regions.

2. The radiation detector according to claim 1, wherein, the plurality of readout circuits that output the spectral signals generate the spectral signals based on the charges generated in the charge generation regions arranged corresponding to the readout circuits and the charges generated in the charge generation regions within a predetermined range of the charge generation regions.

3. The radiation detector according to claim 1 or 2, wherein, the plurality of readout circuits that output the spectral signals generate data representing a plurality of combinations of the energy of the radiation and intensity values corresponding to the energy as the spectral signals.

4. A radiation imaging apparatus, wherein, it has: the radiation detector according to claim 1; and a processor that generates an image based on the intensity signal and the spectral signal output from the radiation detector.

5. The radiation imaging apparatus according to claim 4, wherein, the processor generates information representing an image of the subject as high-resolution luminance information based on the intensity signal and the spectral signal output from the radiation detector, generates information representing the distribution of the physical properties of the subject as low-resolution color information based on the spectral signal output from the radiation detector, and generates a color image of the subject by combining the luminance information and the color information.

6. The radiation imaging apparatus according to claim 4 or 5, wherein, the processor has a function of reconstructing a CT image based on the intensity signal and the spectral signal output from the radiation detector.

Images