Patent Description:
A plurality of radiation detector modules are arranged side by side in a radiation detector. When radiation is detected by a plurality of radiation detector modules arranged side by side, the accuracy of positioning of the radiation detector modules has a great influence on the detection accuracy of the radiation detector. Positioning of radiation detector modules has been performed, for example, on the basis of pins provided on a mounting part of the radiation detector modules.

However, it is difficult to improve the accuracy of positioning based on the pins. In particular, the detection accuracy of a radiation detector is greatly affected by the relative positional relationship between radiation detector modules arranged side by side. However, since positioning based on the pins does not directly adjust the positional relationship between radiation detector modules, it is difficult to improve the positioning accuracy of the radiation detector modules.

<CIT> relates to an automatic or semiautomatic method of assembly of radiation digital imaging tiles to form a one or two dimensional imaging panel whereby the imaging tiles are provided with alignment mark(s), inherent or specific, and a mother board or substrate is also provide with alignment mark(s) and the imaging tiles are mounted on the mother board by means of mechanical pick and place mechanism, whereby the distances of corresponding alignment mark are set to predetermined values, programmed in the automatic machine.

A problem to be solved by the embodiments disclosed in the present description and the drawings is to improve the positioning accuracy of radiation detector modules. However, the problems to be solved by the embodiments disclosed in the present description and the drawings are not limited to the above problem. It is also possible to regard a problem corresponding to each effect according to each configuration illustrated in an embodiment which will be described later as another problem.

The invention provides a a radiation detector module as provided in claim <NUM>.

The through hole is provided only at a position where the mark is visually recognizable from the side of the incident surface.

The mark may include the same material as the first electrode.

The radiation detector module may be provided in a radiation detector including a plurality of radiation detector modules, and the mark may be used for positioning the second electrode and another second electrode in another adjacent radiation detector module.

An electrode film may be provided on the side of the incident surface of the first electrode and supplying a voltage to the first electrode may be further included, and a through hole configured to allow the mark to be visually recognizable from the side of the incident surface may be provided in the electrode film.

A radiation detector may be provided including the aforementioned radiation detector module.

An X-ray CT apparatus may be provided including the radiation detector, wherein the radiation is X-rays.

Hereinafter, a radiation detector module, a radiation detector, and an X-ray CT apparatus of embodiments according to the claimed invention will be described with reference to the drawings.

<FIG> is a configuration diagram of an X-ray CT apparatus <NUM> according to an embodiment. The X-ray CT device <NUM> includes, for example, a gantry <NUM>, a bed device <NUM>, and a console device <NUM>. Although <FIG> shows both a view of the gantry <NUM> from a Z-axis direction and a view from an X-axis direction for convenience of description, there is one gantry <NUM> in reality. In the embodiment, a rotation shaft of a rotary frame <NUM> in a non-tilt state or the longitudinal direction of a top plate <NUM> of the bed device <NUM> is defined as the Z-axis direction, an axis orthogonal to the Z-axis direction and horizontal to the floor surface is defined as the X-axis direction, and a direction orthogonal to the Z-axis direction and perpendicular to the floor surface is defined as a Y-axis direction. The X-ray CT apparatus <NUM> captures a contrast-enhanced CT image for performing imaging examination.

The gantry <NUM> includes, for example, an X-ray tube <NUM>, a wedge <NUM>, a collimator <NUM>, an X-ray high voltage device <NUM>, an X-ray detector <NUM>, a data acquisition system (hereinafter, DAS) <NUM>, the rotary frame <NUM>, and a control device <NUM>.

The X-ray tube <NUM> generates X-rays by radiating thermions from a cathode (filament) toward an anode (target) when a high voltage from the X-ray high voltage device <NUM> is applied thereto. The X-ray tube <NUM> includes a vacuum tube. For example, the X-ray tube <NUM> is a rotating anode type X-ray tube that generates X-rays by radiating thermions to a rotating anode.

The wedge <NUM> is a filter for adjusting an X-ray dose radiated from the X-ray tube <NUM> to a subject P that is an imaging examination target. The wedge <NUM> attenuates X-rays passing therethrough such that the distribution of the X-ray dose applied to the subject P from the X-ray tube <NUM> becomes a predetermined distribution. The wedge <NUM> is also called a wedge filter or a bow-tie filter. The wedge <NUM> is made by processing aluminum so as to have a predetermined target angle and a predetermined thickness, for example.

The collimator <NUM> is a mechanism for narrowing the radiation range of X-rays that have passed through the wedge <NUM>. The collimator <NUM> narrows the radiation range of X-rays by forming a slit, for example, according to combination of a plurality of lead plates. The collimator <NUM> may be called an X-ray diaphragm. A narrowing range of the collimator <NUM> may be mechanically driven.

The X-ray high voltage device <NUM> includes, for example, a high voltage generation device and an X-ray control device. The high voltage generation device has an electric circuit including a transformer, a rectifier, and the like and generates a high voltage applied to the X-ray tube <NUM>. The X-ray control device controls an output voltage of the high voltage generation device according to the X-ray dose to be generated in the X-ray tube <NUM>. The high voltage generation device may boost the voltage by the transformer described above or boost the voltage by an inverter. The X-ray high voltage device <NUM> may be provided on the rotary frame <NUM> or may be provided on the side of a fixed frame (not shown) of the gantry <NUM>.

The X-ray detector <NUM> detects the intensity of X-rays generated by the X-ray tube <NUM>, passed through the subject P and incident thereon. The X-ray detector <NUM> outputs an electrical signal (which may be an optical signal or the like) depending on the intensity of the detected X-rays to the DAS <NUM>. The X-ray detector <NUM> is, for example, a so-called photon counting detector that counts photons to measure X-rays. The X-ray detector <NUM> may be a scintillator. The X-ray detector <NUM> is an example of a radiation detector. The detailed configuration of the X-ray detector <NUM> will be described later.

The DAS <NUM> includes, for example, an amplifier, an integrator, and an A/D converter. The amplifier performs amplification processing on an electrical signal output from each X-ray detection element of the X-ray detector <NUM>. The integrator integrates the amplified electrical signal over a view period. The A/D converter converts an electrical signal indicating the integration result into a digital signal. The DAS <NUM> outputs detection data based on the digital signal to the console device <NUM>.

The rotary frame <NUM> is an annular rotating member that rotates the X-ray tube <NUM>, the wedge <NUM>, the collimator <NUM>, and the X-ray detector <NUM> while holding them facing each other. The rotary frame <NUM> is rotatably supported by the fixed frame around the subject P introduced inside. The rotary frame <NUM> further supports the DAS <NUM>. The detection data output from the DAS <NUM> is transmitted from a transmitter having light-emitting diodes (LEDs) provided in the rotary frame <NUM> to a receiver having photodiodes provided in a non-rotating part (for example, the fixed frame) of the gantry <NUM> according to optical communication and transferred to the console device <NUM> by the receiver. A method of transmitting the detection data from the rotary frame <NUM> to the non-rotating part is not limited to the above-mentioned method using optical communication, and any non-contact transmission method may be adopted. The rotary frame <NUM> is not limited to an annular member as long as it can support and rotate the X-ray tube <NUM> and the like and may be a member such as an arm.

Although the X-ray CT apparatus <NUM> may be, for example, a rotate/rotate-type X-ray CT apparatus (third-generation CT) in which both the X-ray tube <NUM> and the X-ray detector <NUM> are supported by the rotary frame <NUM> and rotate around the subject P, the X-ray CT apparatus <NUM> is not limited to this and may be a stationary/rotate-type X-ray CT apparatus (fourth-generation CT) in which a plurality of X-ray detection elements arranged in an annular shape are fixed to a fixed frame and the X-ray tube <NUM> rotates around the subject P.

The control device <NUM> includes, for example, processing circuitry having a processor such as a central processing unit (CPU) and a drive mechanism including a motor, an actuator, and the like. The processing circuitry realizes these functions by, for example, a hardware processor executing a program stored in a storage device (storage circuit).

The hardware processor means, for example, a circuit (circuitry) such as a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a programmable logic device (for example, a simple programmable logic device (SPLD) or a complex programmable logic device (CPLD)), and a field programmable gate array (FPGA). The program may be configured to be directly embedded in the circuit of the hardware processor instead of being stored in a storage device. In this case, the hardware processor realizes functions by reading and executing the program embedded in the circuit. The hardware processor is not limited to a configuration as a single circuit and may be configured as one hardware processor by combining a plurality of independent circuits to realize respective functions. The storage device may be a non-transitory (hardware) storage medium. Further, a plurality of components may be integrated into one hardware processor to realize respective functions.

The control device <NUM> rotates the rotary frame <NUM>, tilts the gantry of the gantry <NUM>, moves the top plate <NUM> of the bed device <NUM> according to vertical movement, or the like, and causes X-rays to be radiated (allow exposure) from the X-ray tube <NUM>, for example. The control device <NUM> may be provided in the gantry <NUM> or the console device <NUM>.

The bed device <NUM> is a device on which the subject P to be scanned is placed and introduced into the rotary frame <NUM> of the gantry <NUM>. The bed device <NUM> includes, for example, a base <NUM>, a bed driving device <NUM>, the top plate <NUM>, and a support frame <NUM>. The base <NUM> includes a housing that movably supports the support frame <NUM> in the vertical direction (Y-axis direction). The bed driving device <NUM> includes a motor and an actuator. The bed driving device <NUM> moves the top plate <NUM> on which the subject P is placed along the support frame <NUM> in the longitudinal direction (Z-axis direction) of the top plate <NUM>. The top plate <NUM> is a plate-shaped member on which the subject P is placed.

The console device <NUM> includes, for example, a memory <NUM>, a display <NUM>, an input interface <NUM>, and processing circuitry <NUM>. In the embodiment, the console device <NUM> will be described as a separate body from the gantry <NUM>, but the gantry <NUM> may include a part or all of components of the console device <NUM>.

The memory <NUM> is realized by, for example, a semiconductor memory element such as a random access memory (RAM) and a flash memory, a hard disk, an optical disc, or the like. The memory <NUM> stores, for example, detection data, projection data, reconstructed image data, CT image data, and the like. Such data may be stored in an external memory with which the X-ray CT apparatus <NUM> can communicate instead of the memory <NUM> (or in addition to the memory <NUM>). The external memory is controlled by, for example, a cloud server that manages the external memory upon reception of a read/write request by the cloud server.

The display <NUM> displays various types of information. For example, the display <NUM> displays a medical image (CT image) generated by the processing circuitry, a graphical user interface (GUI) image through which various operations by an operator such as a doctor or a technician are received, and the like. The display <NUM> is, for example, a liquid crystal display, a cathode ray tube (CRT), an organic electroluminescence (EL) display, or the like. The display <NUM> may be provided on the gantry <NUM>. The display <NUM> may be a desktop type or a display device (for example, a tablet terminal) capable of wirelessly communicating with the main body of the console device <NUM>.

The input interface <NUM> receives various input operations of the operator and outputs an electrical signal indicating details of the received input operations to the processing circuitry <NUM>. For example, the input interface <NUM> receives input operations such as collection conditions at the time of collecting detection data or projection data, reconstruction conditions at the time of reconstructing a CT image, and image processing conditions at the time of generating a post-processed image from a CT image.

The input interface <NUM> is realized by, for example, a mouse, a keyboard, a touch panel, a drag ball, a switch, a button, a joystick, a camera, an infrared sensor, a microphone, or the like. The input interface <NUM> may be realized by a display device (for example, a tablet terminal) capable of wirelessly communicating with the main body of the console device <NUM>.

In the present description, the input interface is not limited to the one provided with physical operation parts such as a mouse and a keyboard. For example, examples of the input interface also include electrical signal processing circuitry that receives an electrical signal corresponding to an input operation from an external input apparatus provided separately from the device and outputs the electrical signal to the control circuit.

The processing circuitry <NUM> controls the overall operation of the X-ray CT apparatus <NUM>. The processing circuitry <NUM> includes, for example, a control function <NUM>, a pre-processing function <NUM>, a reconstruction processing function <NUM>, and an image processing function <NUM>. The processing circuitry <NUM> realizes these functions by, for example, a hardware processor executing a program stored in a storage device (storage circuit).

The hardware processor means, for example, a circuit such as a CPU, a GPU, an application specific integrated circuit, a programmable logic device or a complex programmable logic device, and a field programmable gate array. The program may be configured to be directly embedded in the circuit of the hardware processor instead of being stored in the storage device. The hardware processor is not limited to a configuration as a single circuit and may be configured as one hardware processor by combining a plurality of independent circuits to realize respective functions. The storage device may be a non-transitory (hardware) storage medium. Further, a plurality of components may be integrated into one hardware processor to realize respective functions.

Each component of the console device <NUM> or the processing circuitry <NUM> may be decentralized and realized by a plurality of hardware circuits. The processing circuitry <NUM> may be realized by a processing device capable of communicating with the console device <NUM> instead of being a component included in the console device <NUM>. The processing device is, for example, a workstation connected to one X-ray CT apparatus or a device (for example, a cloud server) connected to a plurality of X-ray CT apparatuses and collectively executing the same processing as that of the processing circuitry <NUM> which will be described below. Each function included in the processing circuitry <NUM> may be distributed to a plurality of circuits or may be made available by activating application software stored in the memory <NUM>.

The control function <NUM> controls various functions of the processing circuitry <NUM> on the basis of input operations received by the input interface <NUM>. The pre-processing function <NUM> performs pre-processing such as logarithmic conversion processing, offset correction processing, inter-channel sensitivity correction processing, and beam hardening correction on detection data output from DAS <NUM> to generate projection data and stores the generated projection data in the memory <NUM>.

The reconstruction processing function <NUM> performs reconstruction processing on the projection data generated by the pre-processing function <NUM> by a filter correction back projection method, a successive approximation reconstruction method, or the like to generate CT image data and stores the generated CT image data in the memory <NUM>.

The image processing function <NUM> converts the CT image data into three-dimensional image data or cross-sectional image data with an arbitrary cross section by a known method on the basis of an input operation received by the input interface <NUM>. Conversion into the three-dimensional image data may be performed by the pre-processing function <NUM>.

Subsequently, the configuration of the X-ray detector <NUM> will be described. The X-ray detector <NUM> is provided by arranging a plurality of X-ray detector units 15A side by side. <FIG> is an enlarged view showing a part of the X-ray detector unit 15A. The X-ray detector unit 15A includes, for example, a plurality of radiation detector modules (hereinafter, detector modules) <NUM> and a positioning plate <NUM>. The plurality of detector modules <NUM> are arranged in a row and fixed to the positioning plate <NUM>. The plurality of detector modules <NUM> are positioned such that their positions relative to each other can be adjusted. The detector modules <NUM> are an X-ray detection element array.

Each detector module <NUM> includes, for example, a first electrode <NUM>, a detection element <NUM>, a second electrode <NUM>, a substrate layer <NUM>, and a mounting member <NUM>. In the following description, the side of the detector module <NUM> on which the first electrode <NUM> is provided may be referred to as an upper side and the side on which the second electrode <NUM> is provided may be referred to as a lower side.

The first electrode <NUM> is provided on the surface side (upper side) of the detection element <NUM>. The first electrode <NUM> is a high voltage (HV) electrode having a higher potential than that of the second electrode <NUM>. The first electrode <NUM> is formed, for example, by depositing a metal material on the surface of the detection element <NUM>. The first electrode <NUM> may be formed by a method other than vapor deposition.

The detection element <NUM> is formed of, for example, CdTe or CZT. The detection element <NUM> detects radiation incident from an incident surface on the surface side of the detector module <NUM>. The plurality of detector modules <NUM> are provided, for example, by being linearly arranged on the positioning plate <NUM> having a substantially rectangular parallelepiped outer shape. The detection element <NUM> is an example of a radiation detection element.

The second electrode <NUM> is provided on the back surface of the detection element <NUM>. The second electrode <NUM> is provided such that it faces the first electrode <NUM> with the detection element <NUM> interposed therebetween. The second electrode <NUM> is a low voltage (LV) electrode. By energizing the first electrode <NUM> and the second electrode <NUM>, radiation is detected by the detection element <NUM>.

The substrate layer <NUM> is provided on the back surface side of the second electrode <NUM>. The substrate layer <NUM> supports the first electrode <NUM>, the detection element <NUM>, and the second electrode <NUM>. The substrate layer <NUM> includes, for example, a support substrate. Electrical elements such as IC chips are attached to the support substrate. The electrical elements are connected through, for example, a wiring cable.

The mounting member <NUM> is housed in a plurality of positioning holes <NUM> formed in the positioning plate <NUM> and is fixed to the positioning plate by a screw <NUM>. The substrate layer <NUM> is fixed to the mounting member <NUM> with a screw or the like that is not shown. By fixing the substrate layer <NUM> to the mounting member <NUM>, the detector module <NUM> is fixed to the positioning plate <NUM>.

Further, a through hole 61A is formed in the first electrode <NUM>. A part of the surface of the detection element <NUM> is exposed at the portion where the through hole 61A is formed. When the through hole 61A is viewed from above the first electrode <NUM>, the exposed portion on the surface of the detection element <NUM> can be visually recognized. <FIG> is a diagram showing the surface of the detection element <NUM> when the through hole 61A is viewed from above.

A mark <NUM> is provided on the exposed portion on the surface of the detection element <NUM>. The mark <NUM> includes, for example, a portion formed by covering the entire surface of the detection element <NUM> seen through the through hole 61A with the same material as the first electrode <NUM> and hollowing out the central portion thereof. The mark <NUM> is formed by masking the portion of the surface of the detection element <NUM> seen through the through hole 61A, on which the mark <NUM> will be formed, at the time of vapor-depositing the metal to form the first electrode <NUM>. The mark <NUM> has a bordering portion 62A that borders the mark <NUM>, formed on the surface of the detection element <NUM> seen through the through hole 61A.

<FIG> is a diagram showing a state in which the detector module <NUM> is viewed from above. The detector module <NUM> is provided with, for example, a plurality of second electrodes <NUM>. The second electrodes <NUM> all have substantially the same rectangular shape when viewed from above. The plurality of second electrodes <NUM> are arranged in a matrix. One pixel is configured for one second electrode <NUM>.

Two through holes 61A are formed in the first electrode <NUM> such that they face corners where four second electrodes <NUM> at diagonal positions of the first electrode <NUM> among the plurality of second electrodes <NUM> arranged in a matrix face each other. The mark <NUM> is provided on both portions of the surface of the detection element <NUM> seen through the two through holes 61A. The mark <NUM> is provided at a plurality of places (two places in the first embodiment) on the surface of the detection element <NUM>. The through holes 61A are provided only at positions where the mark <NUM> can be visually recognized from the incident surface side. The through holes 61A may be provided at positions other than the positions where the mark <NUM> can be visually recognized from the incident surface side.

<FIG> is a view of the X-ray detector unit 15A when viewed from above. The plurality of detector modules <NUM> are arranged side by side in the X-ray detector unit 15A. Two through holes 61A are formed in each of the plurality of detector modules <NUM>, and the mark <NUM> (refer to <FIG>) is provided at positions seen through the through holes 61A. By aligning the positions of the marks <NUM> seen from the through holes 61A between adjacent detector modules <NUM>, the adjacent detector modules <NUM> are positioned with respect to each other.

The mark <NUM> is provided on the basis of the positions of the second electrodes <NUM>. The mark <NUM> is provided, for example, to position the plurality of detector modules <NUM> such that pixels of adjacent detector modules <NUM> are arranged in an orderly manner. Since the pixels in the detector modules <NUM> are based on the positions and range of the second electrodes <NUM>, the mark <NUM> is used to align the second electrodes <NUM> with the second electrodes <NUM> in another adjacent detector module <NUM>.

Next, a manufacturing procedure of the detector module <NUM> will be described, and then a manufacturing procedure of the X-ray detector unit 15A will be described.

At the time of manufacturing the detector module <NUM>, the substrate layer <NUM> is manufactured first, and the second electrode <NUM> is manufactured on the surface of the substrate layer <NUM> by, for example, vapor deposition. Subsequently, the detection element <NUM> is formed on the surface of the second electrode <NUM>.

After formation of the detection element <NUM>, the first electrode <NUM> is formed by depositing a metal to be the first electrode <NUM> on the surface of the detection element <NUM>. At the time of depositing the metal to be the first electrode <NUM>, portions to be the through holes 61A and portions to be the marks <NUM> are masked. In this manner, the marks <NUM> bordered by the bordering portions 62A formed of the same material as the first electrode <NUM> is formed. The layer of the first electrode <NUM> may be formed after formation of the layer of the bordering portions 62A and the marks <NUM>. The through holes 61A may be formed by depositing a metal to be the first electrode <NUM> on the overall surface of the detection element <NUM> and then performing etching preprocess or the like.

Next, a procedure for manufacturing the X-ray detector unit 15A will be described. <FIG> is a flowchart showing an example of a manufacturing procedure of the X-ray detector unit 15A. At the time of manufacturing the X-ray detector unit 15A, first, the assembled detector modules <NUM> are grasped by, for example, a robot hand and disposed on the positioning plate <NUM> (step S101). In this state, the detector modules <NUM> are not yet fixed to the positioning plate <NUM>.

Subsequently, the detector modules <NUM> are imaged by a camera from above (step S103), and the camera transmits the captured image to a control device that is not shown. The control device analyzes the transmitted image and sets the position of each detector module <NUM> on the basis of the positions of the marks <NUM> provided on each of the plurality of detector modules <NUM> in the image. The control device controls the robot hand on the basis of the set position of each detector module <NUM> and finely adjusts the positions of adjacent detector modules <NUM> (step S105).

Subsequently, after finely adjusting the positions of the detector modules <NUM>, the detector modules <NUM> are additionally imaged with the camera from above and the positions of the detector modules <NUM> are adjusted on the basis of the marks <NUM> provided on each of the plurality of detector modules <NUM> in the image. In position adjustment of the detector modules <NUM>, the marks <NUM> of adjacent detector modules <NUM> are aligned, and further, the second electrodes <NUM> are aligned. Subsequently, the control device determines whether or not position adjustment of the detector modules <NUM> is completed (step S107). If it is determined that position adjustment of the detector modules <NUM> is not completed, the procedure returns to step S105 and the positions of the detector modules <NUM> are finely adjusted.

When it is determined that position adjustment of the detector modules <NUM> is completed, the detector modules <NUM> are fixed to the positioning plate <NUM> by fixing the detector modules <NUM> to the mounting member <NUM> and fixing the mounting member <NUM> to the positioning plate <NUM> by the screw <NUM> (step S109). In this manner, manufacturing of the X-ray detector unit 15A is completed.

In the detector modules <NUM> of the first embodiment, the mark <NUM> for aligning pixels between adjacent detector module <NUM> is provided on the detection element <NUM>. The first electrode <NUM> is provided with the through hole 61A that allows the mark <NUM> provided on the detection element <NUM> to be visually recognizable. Accordingly, positioning is performed while viewing the mark <NUM>, and thus the accuracy of positioning of the detector modules <NUM> can be improved.

Next, the second embodiment will be described. Although the through holes 61A in the first electrode <NUM> are provided only in two places where the marks <NUM> are provided in the first embodiment, the through holes 61A are provided in more places in the second embodiment. For example, the through holes 61A are provided at a plurality of positions including positions where the marks <NUM> can be visually recognized from the incident surface side and other positions. <FIG> is a view of the detector module <NUM> of the second embodiment when viewed from above.

The detector module <NUM> of the second embodiment includes a plurality of second electrodes <NUM> arranged in a matrix as in the first embodiment. Through holes 61A are provided at positions of the first electrode <NUM> corresponding to corners where four second electrodes <NUM> face each other in each of the plurality of second electrodes <NUM>. Accordingly, a larger number of through holes 61A than in the first embodiment is provided.

Marks <NUM> are provided on the surface of the detection element <NUM> seen through two through holes 61A provided at the corners where the four second electrodes <NUM> at diagonal positions of the first electrode <NUM> face each other among the large number of through holes 61A. Accordingly, the first electrode <NUM> is provided with a larger number of through holes 61A than the number of marks <NUM>.

The large number of through holes 61A provided in the first electrode <NUM> are provided corresponding to the positions of the second electrodes <NUM>. Accordingly, the plurality of through holes 61A are arranged symmetrically on the surface of the first electrode <NUM>, so to speak, arranged and formed in a well-balanced manner. Further, since the through holes 61A are provided at the corners where the four second electrodes <NUM> face each other, the area of a portion of the first electrode <NUM> facing the second electrodes <NUM> is not so small.

<FIG> is a view of the X-ray detector unit 15A of the second embodiment when viewed from above. In the X-ray detector unit 15A of the second embodiment, the plurality of detector modules <NUM> are each provided with marks <NUM> (refer to <FIG>) at positions seen through the two through holes 61A at diagonal positions of the first electrode <NUM>. By aligning the positions of the marks <NUM> seen through the through holes 61A between adjacent detector modules <NUM>, the adjacent detector modules <NUM> are positioned with respect to each other.

The detector module <NUM> of the second embodiment has the same effect as that of the detector module <NUM> of the first embodiment. Further, in the detector module <NUM> of the second embodiment, the first electrode <NUM> is provided with a large number of through holes 61A corresponding to the positions of the second electrodes <NUM>. Accordingly, a voltage is evenly applied to the second electrodes <NUM>, in other words, evenly applied to the pixels in the first electrode <NUM>, and thus the detection accuracy of the detection element <NUM> can be improved.

In each of the above embodiments, the mark <NUM> has a substantially cross shape but may have other shapes. <FIG> are views all showing other examples of marks. For example, as shown in <FIG>, a mark <NUM> is formed of the same material as the first electrode <NUM> or a different material on the surface of the detection element seen through the through hole 61A. In this case, the mark <NUM> may be formed on the surface of the detection element <NUM> before the first electrode <NUM> is formed. Further, the mark <NUM> may be formed by masking a portion excluding the portion to be the mark <NUM>, or the mark <NUM> may be formed through etching processing.

In addition, as shown in <FIG>, a circular mark <NUM> may be formed on the surface of the detection element seen through the through hole 61A. Further, as shown in <FIG>, a substantially T-shaped mark <NUM> may be formed on the surface of the detection element seen through the through hole 61A. When the cross-shaped marks <NUM> and <NUM> and the T-shaped mark <NUM> are formed, the marks <NUM>, <NUM>, and <NUM> may be formed such that the direction of a straight line portion is parallel to the outside of the body in the plurality of detector modules <NUM>.

In each of the above embodiments, the mark <NUM> is provided on the surface of the detection element <NUM>. On the other hand, the mark <NUM> may be provided on the surface of the first electrode <NUM>. In this case, the mark <NUM> may be provided at the same time when the first electrode <NUM> is formed by masking the place where the mark <NUM> will be provided and depositing a metal on the surface of the detection element <NUM>. The mark <NUM> may be formed by performing etching processing after formation of the first electrode <NUM>. The mark <NUM> may be provided on both the surface of the first electrode <NUM> and the surface of the detection element <NUM>.

Further, although two marks <NUM> are provided in each of the above embodiments, a single mark <NUM> may be provided or three or more marks <NUM> may be provided. Although the mark <NUM> is provided at the same position between adjacent detector modules <NUM>, the mark <NUM> may be provided at different positions between adjacent detector modules <NUM>. The mark <NUM> may be formed of a material other than the same material as the first electrode <NUM>. For example, the mark <NUM> may be provided by applying a paint or the like on the surface of the detection element <NUM> or the first electrode <NUM>.

Next, the third embodiment will be described. Although the through hole 61A for allowing the mark <NUM> to be visually recognizable from the incident surface side is provided in the first electrode <NUM> in the first embodiment, a through hole that allows the mark <NUM> to be visually recognizable from the incident surface side is also provided in an electrode film provided on the upper side of the first electrode <NUM> in the third embodiment.

<FIG> is an enlarged view showing a part of an X-ray detector unit 15B according to the third embodiment. The X-ray detector unit 15B shown in <FIG> includes an electrode film <NUM> additionally provided on the X-ray detector unit 15A shown in <FIG>. The electrode film <NUM> is provided on the upper side of the first electrode <NUM> of each detector module <NUM> included in the X-ray detector unit 15A. The electrode film <NUM> is conductive and has a film shape. The electrode film <NUM> uniformly supplies a voltage supplied from a voltage source (not shown) to the first electrode <NUM> of each detector module <NUM>.

Through holes 67A are formed in the electrode film <NUM>. At the portions where the through holes 67A are formed, parts of the surface of the detection element <NUM> are exposed through the through holes 61A of the first electrode <NUM>. When the through holes 67A are viewed from above the electrode film <NUM>, the exposed portions on the surface of the detection element <NUM> can be visually recognized. For example, the mark <NUM> as shown in <FIG> is provided on the exposed portions on the surface of the detection element <NUM>.

<FIG> is a view of the X-ray detector unit 15B according to the third embodiment when viewed from above. A plurality of detector modules <NUM> are arranged side by side in the X-ray detector unit 15B. In each of the plurality of detector modules <NUM>, two through holes 61A are formed in the first electrode <NUM> and the marks <NUM> (refer to <FIG>) are provided at positions seen through the through holes 61A. Further, through holes 67A are provided at positions corresponding to the marks <NUM> of the electrode film <NUM>. When the through holes 67A are viewed from above the electrode film <NUM>, the marks <NUM> on the surface of the detection element <NUM> can be visually recognized through the through holes 61A of the first electrode <NUM>. By aligning the positions of the marks <NUM> seen through the through holes 67A between adjacent detector modules <NUM>, the adjacent detector modules <NUM> can be positioned with respect to each other.

In the X-ray detector unit 15B of the third embodiment, marks <NUM> for aligning pixels between adjacent detector module <NUM> are provided on the detection element <NUM>. The first electrode <NUM> is provided with the through holes 61A that allow the marks <NUM> provided on the detection element <NUM> to be visually recognizable, and the electrode film <NUM> is provided with through holes 67A that allow the marks <NUM> provided on the detection element <NUM> to be visually recognizable via the through holes 61A. Accordingly, positioning is performed while viewing the marks <NUM>, and thus the accuracy of positioning of the detector module <NUM> can be improved.

Next, the fourth embodiment will be described. In the fourth embodiment, processing of estimating the position of each pixel using a pencil beam is performed at the time of positioning the detector module <NUM>. <FIG> is a diagram showing a state in which processing of estimating the position of each pixel is performed using a pencil beam PB according to the fourth embodiment.

As shown in <FIG>, an X-ray source <NUM> radiates the pencil beam PB (X-ray) to the detector module <NUM> from above the first electrode <NUM> of the detector module <NUM>. At this time, radiation by the X-ray source <NUM> is performed while moving the radiation position of the pencil beam PB in the detector module <NUM> in a predetermined direction (for example, a direction D). Further, radiation by the X-ray source <NUM> may be performed while moving the radiation position of the pencil beam PB in the detector module <NUM> in a direction orthogonal to the direction D on the upper side surface of the first electrode <NUM>. The pencil beam PB has, for example, a beam size equal to or less than the size of each pixel. The pencil beam PB may have a beam size larger than the size of each pixel.

The positions of pixels (the positions of the second electrodes <NUM>) are estimated by observing change in an electrical signal output from the detector module <NUM>, accompanied by change in the radiation position of the pencil beam PB. In the example shown in <FIG>, an output value (electrical signal) of the detector module <NUM> shows a peak PK when radiation positions of the pencil beam PB are positions PT1, PT2, and PT3. In this case, it can be estimated that the positions PT1, PT2, and PT3 at which the output value indicates the peak PK are center positions of pixels (center positions of the second electrode <NUM>). Such estimation processing may be performed, for example, in the processing circuitry <NUM> of the console device <NUM>, and the estimation result may be output to the display <NUM>.

In the X-ray detector unit of the fourth embodiment, the position of each pixel is estimated by using a pencil beam in order to align pixels between adjacent detector modules <NUM>. Accordingly, the accuracy of positioning of the detector module <NUM> can be improved.

According to at least one embodiment described above, it is possible to improve the accuracy of positioning of the radiation detector module by including a radiation detection element that detects radiation incident from an incident surface, a first electrode provided on an incident surface side of the radiation detection element, a second electrode provided to face the first electrode having the radiation detection element interposed therebetween, and a mark provided on at least one of the incident surface of the radiation detection element and the first electrode.

Claim 1:
A radiation detector module (<NUM>) comprising:
a radiation detection element (<NUM>) that includes an incident surface and is configured to detect radiation incident on the incident surface;
a first electrode (<NUM>) provided on a side of the incident surface of the radiation detection element (<NUM>);
a second electrode (<NUM>) provided to face the first electrode (<NUM>) through the radiation detection element (<NUM>); and
a mark (<NUM>, <NUM>, <NUM>, <NUM>) provided on the incident surface of the radiation detection element (<NUM>) , the radiation detector module (<NUM>) characterized in that the first electrode (<NUM>) has a through hole (61A) configured to allow the mark (<NUM>, <NUM>, <NUM>, <NUM>) to be visually recognizable from the side of the incident surface.