X-ray image detector device

Abstract

An X-ray image sensor (1050) having a plurality of pixels (350), each of the pixels (350) having a pixel structure with two drivers, wherein each pixel (350) has two thin-film transistors (320, 330), one even and one odd, and two thin-film photodiodes (210), wherein one of the two thin-film transistors (330) has a source electrode (323) connected to a cathode (211) of one of the two thin-film photodiodes (210), a gate electrode (321) connected to an odd-numbered control line (410), and a drain electrode (322) connected to a signal output line (450); wherein the other of the two thin-film transistors (320) has a source electrode (323) connected to a cathode (211) of the other of the two thin-film photodiodes (210), a gate electrode (321) connected to an even-numbered control line (420), and a drain electrode (322) connected to the signal output line (450); wherein the signal output line (450) is connected to a charge readout circuit (500), wherein the two anodes (212) of the two thin-film photodiodes (210) are connected to a common grounding line (490) of the pixels (350); The charge readout circuit (500) converts a quantity of the charges into a voltage which is transferred to a charge difference collector; the charge difference collector is a differentiation circuit comprising a reference charge register (510) and a signal charge register (520); The charge readout circuit receives signals when the thin-film transistor (320, 330) is in the off and on state, which are stored in the reference charge register (510) and the signal charge register (520), respectively, and a signal difference between the reference charge register (510) and the signal charge register (520) is fed into an analog-to-digital converter circuit to avoid the influence of slight differences between thin-film transistors (320, 330) and thin-film photodiodes (210) during manufacturing on the signal detection.

Description

Technical field

[0001] The present invention relates to an X-ray image detector device, in particular an image detector device which uses X-rays to examine the internal structure of a material, which receives the visible radiation converted from X-rays through a thin-film transistor array, and which obtains a two-dimensional image by individually measuring the charge generated on each thin-film photodiode and by an image reduction treatment, which belongs to the field of X-ray digital image generation. Technical background

[0002] It is known that X-rays can penetrate materials, and also that different materials have different absorption capacities for X-rays. Using the material's penetration properties and phosphorescence, the internal structure of the material can be detected by X-rays. Currently, a film photography method is used in the practical application of X-ray measurement technology. The image quality of film photography is higher, and it can also provide reliable information about the actual nature of defects in the detected materials. However, this method inevitably has some disadvantages, such as a complicated operating process, high operating costs, difficulties in storing the results, and inconveniences in data retrieval and transport.

[0003] To solve the aforementioned problems, digital radiography was invented at the end of the 1990s. The fundamental principle of digital radiography lies in the use of a flat-panel detector based on amorphous materials. The flat-panel detector consists of a scintillator (usually iodine cesium or phosphorus), a thin-film photodiode array, and a thin-film transistor array.When the incoming X-rays reach the scintillator and are absorbed, the excited visible radiation is directed to an underlying photodiode, converted into an electrical signal, which is then fed into the film transistor where it becomes a storage charge. These storage charges are sequentially routed to a peripheral circuit, triggered by a control circuit. After data readout, the signal undergoes amplification processing by an amplifier and is then converted into a binary digital signal. This signal is transmitted via a cable to a display and then shown. Because the image in an X-ray digital imaging system is formed from digital pixels, it offers advantages such as high spatial resolution, high image clarity, and high dynamic contrast.Almost the same quality and resolution of image production as with the film photography process can be achieved, while at the same time image processing via computer is simplified.

[0004] A digital X-ray imaging system with a flat-screen detector offers significant application potential in non-destructive testing and evaluation, container scanning, circuit board inspection, and medical applications. Chinese patents (or patent applications) CN 1 910 902 A, CN 1 455 584 A, CN 101 147 682 A, CN 101 175 440 A, CN 101 221 137 A, CN 101 044 983 A, and CN 101 422 372 A open up a wide range of applications for X-rays in medical imaging, non-destructive testing of industrial products, examination of the structure of living organisms, and safety inspections. Reference can be made to the patents or patent applications themselves; they are not detailed in this application.

[0005] In X-ray digital imaging technology, the main challenge lies in generating an image from the thin-film transistor array. This process is the reverse of the image generation principle used in liquid crystal displays. The technical problem to be solved is to adapt a suitable combination of thin-film transistor structures to convert a visible light image into an electrical signal and then reconstruct the image. Currently, several technical solutions for image generation exist, such as linear scanning, but current techniques still have drawbacks like longer exposure times and low spatial resolution. Summary

[0006] The present invention is therefore based on the main technical problem of providing an X-ray image sensor. This image sensor is intended to solve technical difficulties in the aforementioned inverse process, simplify the manufacturing process, and facilitate its use.

[0007] The present invention therefore has the further technical objective of providing an X-ray image detector device using the X-ray image sensor.

[0008] The present invention provides the following solution for achieving the above objectives: An X-ray image sensor has multiple pixels, each of which has a pixel structure with dual control, whereby Each pixel has two thin-film transistors, one even and one odd, and two thin-film photodiodes.

[0009] Source electrodes of the thin-film transistors are each connected to the cathodes of the thin-film photodiodes, with gate electrodes each being connected to an odd-row control line and an even-row control line, with drain electrodes being connected to a common signal output line, and with the signal output line being connected to the charge readout circuit. and wherein the anode of the two thin-film photodiodes are connected to a common grounding conductor of the pixels.

[0010] In this process, a charge readout circuit receives signals when the thin-film transistor is in a blocked and an open state, which are stored in a reference charge register and a signal charge register, respectively, and the signal difference between the reference charge register and the signal charge register is input into an analog-to-digital conversion circuit.

[0011] A line drive circuit controls the opening and closing of the thin-film transistors, and simultaneously controls the storage and output of the signal in the reference charge register and in the signal charge register.

[0012] The X-ray image sensor also has a selector switch for a multi-signal output, the selector switch for the multi-signal output being controlled by a line drive circuit, and by switching the switch, charges stored on different pixels are discharged into the same signal output line.

[0013] The line drive circuit adheres to a glass substrate, the selection switch for the multi-signal output is integrated into the line drive circuit, and line drive signal lines are manufactured such that they are connected to finger-shaped line drive electrodes, which receive input signals from the line drive circuit.

[0014] The charge readout circuits are distributed across the left and right sides of the X-ray image sensor, and the charge readout circuits on each side are connected to only half of the total number of pixels in each row.

[0015] An X-ray image detector device comprises a scintillator that converts the X-rays into visible radiation, a data integration processing unit, the X-ray image detector device having a plurality of X-ray image sensors, the X-ray image sensors being arranged in a matrix arrangement, and the scintillator being positioned directly opposite an X-ray source, the X-ray image sensors arranged in a matrix arrangement being located on the back of the scintillator, and the data integration processing unit being connected to the X-ray image sensors.

[0016] The X-ray image detector device further includes an X-ray dose sensor, the X-ray dose sensor being located on the back of the X-ray image sensors.

[0017] The X-ray dose sensor generates a feedback signal via an output unit of the X-ray dose feedback, with the feedback signal being provided by the X-ray source.

[0018] The X-ray image detector device is activated the moment the X-ray dose sensors begin to accumulate charge, and the accumulation of pixel charge of the X-ray image detector device is stopped the moment the X-ray dose sensor meets dosage requirements.

[0019] The X-ray image detector device further comprises an anti-scatter grid, wherein the anti-scatter grid is arranged directly opposite the X-ray source, with the scintillator being arranged on the back side of the anti-scatter grid.

[0020] The scattering beam grid can be replaced by a virtual grid. The X-ray image detector device presented in the present invention can also be implemented using existing LCD manufacturing technology, which significantly reduces manufacturing costs.

[0021] When this X-ray image detector device is used, a complete digital X-ray image can be obtained with short exposure time and high spatial resolution, and it enables extensive technical support in applications such as non-destructive testing of industrial products and minimally invasive surgery performed under visual guidance. Brief description of the characters

[0022] The present disclosure will be better understood from the following description, which is given solely for illustrative purposes and is therefore not limiting to the present disclosure, wherein: Fig. 1 a block diagram of the general electrical principle of the present invention; Fig. 2 is a schematic view of the structure of an X-ray excited and light-emitting scintillator; Fig. 3 a graphical representation of the distribution of the wavelength characteristics of the light emitted by the scintillator; Fig. 4(a) and Fig. 4(b) each represent the circuit structure of individual pixels of the present invention and the circuit structure of a single pixel used in an LCD display; Fig. 5(a) and Fig. 5(b) show the pixel structure used in an LCD display and the unique dual-drive pixel structure according to the present invention; Fig. 6 illustrates a unique structure comprising two charge registers and a differential switching structure in the present invention; Fig. 7 is a schematic view of pixel structures drawn on a glass substrate according to the invention; Fig. 8 represents a connection relationship between a substrate comprising a thin-film photodiode group and a thin-film transistor group, and the external circuit; Fig. 9 describes a connection between the high-density, finger-shaped electrodes produced on the glass substrate and the flexible circuit board; Fig. 10 represents an entire assembly structure of the present invention and a connection concept of the circuit; Fig. 11 shows a first embodiment of the present invention for the non-destructive observation of an indisassemblable armaments product, wherein a detailed internal structure of the detected product is obtained by cone-beam computed tomography (CT); Fig. Figure 12 shows a second embodiment of the present invention for observing an active human organ, such as a heart, in real time during an operation. Detailed description

[0023] The basic concept of the present invention lies in receiving visible radiation, converted from X-rays by a scintillator, using thin-film transistor arrays. A thin-film transistor array, together with a thin-film photodiode array, forms a flat-screen detector. Different charges are generated on the thin-film photodiodes as the intensity of the visible radiation changes. By opening and closing the switches of the thin-film transistor arrays, the charges present on the thin-film photodiodes are measured one after the other to obtain the change in X-ray absorption, thereby generating a set of two-dimensional image data. Based on this data, the necessary information can be obtained for reducing the static two-dimensional image and the dynamic two-dimensional image, and the image details can be recovered through image reconstruction computation.

[0024] Fig. Figure 1 is a block diagram of the entire electrical principle of the X-ray image detector device described in the present invention. This X-ray image detector device 1000 comprises a scintillator 100 that converts the X-rays into visible radiation, a thin-film photodiode array 200 and a thin-film transistor array 300, manufactured by semiconductor fabrication processes and arranged in a matrix, a line drive circuit 400 for the coordinated control of a component group for photoelectric conversion, a charge readout circuit 500 for reading the component group for photoelectric conversion, an analog-to-digital conversion circuit 600 for converting the charge into data, an X-ray dose sensor 700, an output unit for X-ray dose feedback 750, and a protective layer 800 for protecting the electrical circuit from X-ray radiation.A data integration unit 900, performing a data integration and processing function, and a computer system 1300, which reconstructs the signal of the photoelectric components. The X-ray image detector device 1000 allows image data about the absorption level of the X-rays from the detected material to be obtained at a specific location in two-dimensional coordinates. This image data is stored and transferred in the computer system 1300, where a readable image is reconstructed and finally displayed on the image display 950. The reduced image can be a static image or a continuously dynamic image and can be used for non-destructive industrial testing, observation and verification of anatomy, and other applications for X-ray analysis.

[0025] Fig. Figure 2 is a schematic representation of the structure of the scintillator that converts X-rays into visible radiation. The scintillator 100 comprises a material such as thallium-doped cesium iodide or gadolinium oxysulfide. The outer layer of the scintillator 100 is a thin layer 130 made of amorphous carbon or carbon fiber, with a thickness of 0.5–3 mm, and therefore hardly blocks the X-rays. Beneath this thin layer 130 is the vertically arranged scintillator group 120. Considering that the transmission efficiency of the radiation is highest in the vertical direction, the scintillator group 120 is arranged vertically. In the vertical direction, the array consisting of thin-film photodiodes 210 can achieve maximum irradiation, while simultaneously minimizing interference with the surrounding thin-film photodiode.During the manufacturing of a flat panel detector, the scintillator 100 and the thin-film photodiode must be tightly bonded together. Bonding methods include bonding by pressure, vacuum adsorption under reduced pressure, bonding with a translucent adhesive, bonding by growing or coating the scintillation materials onto the thin-film photodiode assembly.

[0026] When an X-ray beam 110 strikes the scintillator 100 from the outside, the incident X-rays are blocked and absorbed by the vertically arranged scintillator group 120 and then converted into visible light 140. As the Fig. Figure 3 shows that the visible radiation 140, which was converted by the X-rays 110 incident on the scintillator 10, has a peak value between 530 and 580 nm, and the spectral range can extend from 350 to 700 nm. This radiation has a very short delay effect and can be attenuated to less than 1% of the X-ray radiation brightness within 1 ms after the X-ray beam disappears.

[0027] The X-ray image sensor (hereinafter referred to as image sensor) 1050 described in this invention uses a unique odd or even pixel 350 with dual control. Each pixel row is controlled, in an even or odd manner, by an odd-row row control line 410 and an even-row row control line 420, respectively, and two pixel columns share a signal output line 450 and a charge readout circuit 500. Therefore, the number of signal output lines 450 is equal to half the number of pixel columns. The number of control lines is twice the number of pixel rows, and the control lines each control the odd-numbered thin-film transistors 330 and the even-numbered thin-film transistors 320 from the two sides of the image sensor.

[0028] Fig. 4(a) and Fig. Figure 4(b) shows the circuit structure of a single pixel of this invention and the circuit structure of a single pixel used in an LCD display. In contrast to the brightness driver circuit 505 used in an LCD display, the current direction on the signal output line 450 in the pixel circuit structure according to the present invention is opposite to the current direction of the brightness signal control line 440 used in the LCD display. Furthermore, unlike the thin-film transistor structure 310 used in an LCD display, the source electrode 323 of the thin-film transistors 320, 330 is connected to the thin-film photodiode structure 210, and the drain electrode 322 is connected to the signal output line 450.

[0029] How Fig. As shown in Figure 4(a), a charge is generated on the thin-film photodiode structure 210, which receives the photons of the visible radiation. A thin-film photodiode has two electrodes, with the anode of the thin-film photodiode 212, which corresponds to the anode of the conventional photodiode, being connected to the common grounding line of pixel 490, and the cathode of the thin-film photodiode 211, which corresponds to the cathode of the conventional photodiode, being connected to the source electrode of the thin-film transistor 323. Before the charge accumulates, a negative bias voltage of 1–12 volts can be applied to the thin-film photodiode via the common grounding line of pixel 490.

[0030] Fig. 5(a) and Fig. Figure 5(b) shows the pixel structure used in an LCD display and the specific pixel structure with dual control according to this present invention. In contrast to the single-drive pixel structure 340 used in an LCD display, the image sensor control according to the present invention uses two cooperating drives. Furthermore, unlike the pixel capacitors 220 used in an LCD display, there are actually no pixel capacitors 220 in the image sensor of the present invention; instead, the thin-film photodiode structure 210 is located at this position.

[0031] How Fig. Figure 5(b) shows that when the voltage from the gate electrode 321 of the thin-film transistors 320, 330 is negatively biased, there is a high resistance between the source electrode 323 and the drain electrode 322. When the gate electrode 321 of the thin-film transistors is positively biased, there is a low resistance between the source electrode 323 and the drain electrode 322 of the thin-film transistors 320, 330. In this way, the charge generated after receiving photons from the thin-film photodiode can be discharged through the source electrode 323 and the drain electrode 322 of the thin-film transistor to the signal output line 450. The signal output line 450 is connected to the external charge readout circuit 500.

[0032] The Fig. Figure 6 shows how the charge readout circuit 500 converts the electrical charge into a voltage, which is then transmitted via the output lines of the charge readout circuit 560 to the charge differential collector 550, and how the charge differential signal 570 is transmitted to the analog-to-digital conversion circuit 600. The charge differential collector 550 is a differential circuit. The charge readout circuit 500 can acquire the signals during the switching on and off phases of the thin-film transistors and then store them in the reference charge register 510 and the signal charge register 520, respectively. The storage and output of the signal from the two registers are controlled by the line drive control circuit 400. The signal difference between the two registers is transmitted to the analog-to-digital conversion circuit 600.This method of operation, namely storing the signal with two samples and then calculating the difference, ensures the signal testing precision of the image sensor 1050. At the same time, it also avoids signal testing variations caused by slight differences in the manufacturing of the thin-film transistor group 300 and the thin-film photodiode group 200. The charge difference collector 550 is controlled by a changeover switch control circuit 470 and exports the obtained charge difference signal 570 during conversion by a modal converter.

[0033] Fig. Figure 7 is a schematic representation of the present invention, wherein the pixel structure with dual control is applied to a glass substrate. The glass substrate is a conventional component in a flat panel display detector and is not described in detail here. Unlike the line drive line 450 used in an LCD display, the pixels of each line in this present invention are divided into even and odd pixels, which are controlled by the odd-row line drive line 410 and the even-row line drive line 420, respectively. The opening and closing of the thin-film transistors 320 and 330 is controlled by the line drive control circuit 400. When the odd-row thin-film transistor 330 is open, the charge stored on the thin-film photodiode structure 210 connected to the odd-row thin-film transistors 330 is discharged onto the line drive line 450.When the even-row thin-film transistor 320 is open, the charge stored on the thin-film photodiode structure 210 connected to the even-row thin-film transistors 330 is discharged onto the row control line 450. In this present invention, the effective area of ​​the thin-film photodiode structure 210 occupies the largest area of ​​the pixel 260. The aim of such a design is to absorb the visible radiation converted from X-rays as much as possible through the thin-film photodiode and then convert it into charge.

[0034] How Fig. Figure 8 shows the precision range of the analog-to-digital conversion circuit 600 to be 14-16 bits. The image sensor 1050 incorporates the analog-to-digital conversion circuit 600 in a quantity equal to or half the number of charge readout circuits 500, depending on whether a multiplex switch is additionally installed at one end of the analog-to-digital conversion circuit 600 to switch the corresponding charge readout circuit 500. To ensure the accuracy of the output value from the analog-to-digital conversion circuit 600, the timing of signal acquisition and conversion is controlled by the line drive control circuit 400.

[0035] The image sensor 1050 presented in this invention consists of pixels with a number M×N, where M is the number of row controls and N is twice the number of charge readout circuits. Because M and N are often large, many integrated control units for the odd and even rows of the row control circuit 480 and many charge readout circuits 500 are needed to control the readout of all signals present on an image sensor 1050. The sequential control of the control unit for the odd and even rows of the row control circuit 480 is provided by the row control control circuit 400. A plurality of chips of the charge readout circuits 500 receive the charge of all pixels of the rows that are simultaneously opened by the control circuit, and these are then passed to the outside by the analog-to-digital conversion circuit 600.The multiple data streams are to be combined onto a single data line by the multiplex data control unit 610. The data in odd and even lines are then combined by the data integration processing unit into a single image frame signal, which is sent to a computer and then to the display. In one embodiment of this invention, a readout chip with 2N charge readout circuits 500 can be integrated, where N is an integer between 6 and 9. Certainly, N can also take on other positive integer values.

[0036] The multi-signal output selector switch 460, located on the image sensor 1050, is controlled by the line drive control circuit 400. Switching the switch allows the charges of different pixels 260 to be discharged into a signal output line 450. The multi-signal output selector switch 460 allows different columns of pixels to utilize a charge readout circuit 500, ensuring a design with consistent electrical characteristics. More importantly, this multi-signal output selector switch 460 can efficiently discharge the charges generated on multiple pixels 260 simultaneously into the charge readout circuit 500, thereby achieving higher sensitivity and saturation.Furthermore, this selector switch for multi-signal output 460 also has the ability to change the line resolution of the image sensor 1050. Together with a line control line start operation, it can implement the combination of pixels 260 in the number K x J. The number of selector switches for multi-signal output 460 is J, where J is an integer, at least 2, and usually half the number of rows. The number of required charge readout circuits is obtained by dividing the number of pixel columns of the image sensor 1050 by 2J. K is the number of control lines that can be started simultaneously. The minimum number of combinable pixels 260 is 2 x 2, and the maximum number that can be combined is K x J. According to the application requirements, K cannot be equal to J, so that after the combination, a non-square pixel 260 can be obtained.

[0037] In certain situations requiring the observation of dynamic images, the readout speed can be significantly increased by sampling the pixels of the 1050 image sensor in combination. For the pixels in the 1050 image sensors with MxN, sampling in a 2x2 pixel combination mode results in a readout speed four times higher than for 1x1 pixels. This combined sampling method is very useful for dynamic images; theoretically, the speed can be increased by a factor of KxJ, and in practice, the speed can be increased by a factor of KxJ / 2.

[0038] How Fig. Figure 8 shows that, to reduce the resistance and distributed capacitance of the signal line, the charge readout circuit 500 can be distributed on the right and left sides of the image sensor 1050, and the charge readout circuits 500 distributed on each side are connected to only half of the total number of pixel rows. This design can reduce the resistance and capacitance of the signal lines by half and also increases the signal-to-noise ratio of the image sensor 1050.

[0039] Fig. Figure 9 shows that the 1050 image sensor can have very high spatial resolution. For example, in a Fig. In the embodiment shown in Figure 11, the total number of image sensors 1050 is 3072. The charge readout circuits arranged on both sides separately connect the 1536 pixels located above and below. In this configuration, the pixel dimensions are very small, ranging from 50 µm to 300 µm, and the signal and control lines are very closely spaced. To improve the connection with the external charge, the signal line connects to the finger-shaped output electrode 455 located on the image sensor 1050. The signal output wires 450, made from a flexible circuit board, connect the external circuit and the image sensor 1050. This reciprocal connection is achieved using a method involving metal particles and adhesive.Because the density of the control lines is higher than that of the signal wires, the line drive circuit 400 must be attached to the glass substrate of the image sensor 1050, and the selector switch for the multi-signal output 460 is integrated into the line drive control circuit 400. Line drive signal lines 430, made from the flexible circuit board, are directly connected to finger-shaped line drive electrodes 435, which receive input signals from the line drive control circuit 400.

[0040] How Fig. As shown in Figure 10, the X-ray image detector device 1000 presented in this invention further comprises an image sensor 1050, an anti-scatter grid (or the virtual grid; information can be found in patent specification CN 100 510 725 C), a scintillator 100, an X-ray dose sensor 700, and a data integration processing unit 900. The data from the X-ray image detector device 1000 are processed in the image processing computer system 1300 and then sent to the image display 950 for redisplay. This use is mainly illustrated in the following exemplary embodiments. In this present invention, several X-ray dose sensors 700 can be arranged on the back side of the image sensor 1050.This X-ray dose sensor 700 allows the intensity signal of the X-rays to be fed back through the dose control circuit to the output unit of the X-ray dose feedback 750, so that the incident X-rays 110 passing through the material are precisely suited to the requirements regarding the detector area. Because the flat-screen detector of this invention is very thin, the X-rays can easily pass through it; therefore, there is no interference with image generation when the X-ray dose sensor 700 is positioned on the back of the pixel group of the image sensor 1050. This is, of course, one of the special features of this invention.

[0041] When X-rays are emitted, the X-ray dose sensor 700 generates a feedback signal via the output unit of the X-ray dose feedback 750, based on the energy and number of X-ray quanta. This feedback signal is then provided to the X-ray source. When the radiation dose received by the image sensor 1050 meets the requirements of the image detector, the X-rays stop emitting. Thanks to the function of the X-ray dose sensor 700, the radiation dose can be effectively controlled, and the detected image will be in optimal condition. In practice, the shape of the material being detected determines whether all or only some of the X-ray dose sensors 700 should be activated.

[0042] The activation time of the X-ray image detector 1000 is the point at which the X-ray dose sensors 700 begin to accumulate charge. The end time of pixel charge accumulation in this X-ray image detector 1000 is the point at which the X-ray dose sensors 700 reach the dose requirement. Specifically, the X-ray source determines the tube voltage and current in advance, and the irradiation time is determined based on the integral value of the feedback signal from the X-ray dose sensors 700. When the integral value of the feedback signal reaches the threshold, the X-ray irradiation stops. This type of feedback control simplifies the charge design of the X-ray image detector and enables full automation during operation.

[0043] The image sensor 1050 and the corresponding X-ray image detector device 1000 presented in this invention can be manufactured using existing production techniques, thus significantly reducing manufacturing costs. This is also one of the outstanding advantages of this invention.

[0044] Fig. Figure 11 represents a first application embodiment. In this embodiment, the X-ray image detector device can be used to detect a non-disassemblable industrial product and then to perform non-destructive detection of the detected material. The detected material 1200 is arranged on a rotary table 1250. The X-rays emitted from the X-ray tube 1100 penetrate the detected material 1200, which consists of various substances that correspondingly change the intensity of the X-rays penetrating the detected material. This change is determined by the absorption level of the X-rays penetrating the detected material. These X-rays contain the internal information of the detected material 1200.When such X-rays are emitted into the X-ray image detector device, the X-rays 110 are converted into a visible image in the scintillator unit 120, and this image is generated by the computer system 1300 via the aforementioned process. Because the rotary table 1250 rotates at an angle with each exposure of the X-rays, after a rotation of 180° or 360° has been completed sequentially, all information about the internal structure of the detected material 1200 can be obtained, and then a three-dimensional cone bundle reconstruction technique can be used to obtain the reconstructed material structure.

[0045] Fig. Figure 12 presents a second application example. In this example, the X-ray image detector device for human health examination and disease treatment can be used to enable the operation of minimally invasive surgery performed under direct vision.

[0046] Vital organs such as the heart may require minimally invasive surgery due to disease. Such vital organs can be considered the target material 1200. After the X-ray tube 1100 emits the X-rays 110, they penetrate the target material and strike the X-ray image detector 1000. Through this process, a dynamic, real-time image can be obtained. This image not only includes the target organ but also simultaneously displays the device and implantation object placed by the physician. Because the image is real-time, the physician can use the device to guide the implantation object into the target organ and thus achieve the treatment goal.Simultaneously, by changing the angle of the X-rays in different directions, the detected material can be observed. Such machines often have the function of rotating around the horizontal axis of rotation of the body and also around the vertical axis of rotation of the body. The X-ray images obtained at different angles can be used by the computer to create a three-dimensional reconstruction for image processing, in order to obtain the detailed internal structure of the organs.

[0047] The image sensor and the corresponding X-ray image detector device disclosed in the present invention have been described in detail above. With respect to a person skilled in the art with the usual skills, any obvious modifications that do not deviate from the essential spirit of this present invention shall be considered an infringement of the patent rights of this present invention and shall have corresponding legal consequences.

Claims

[1] An X-ray image sensor (1050) having a plurality of pixels (350), each of the pixels (350) having a pixel structure with two drives, wherein each pixel (350) comprises two thin-film transistors (320, 330), each of even and odd, and two thin-film photodiodes (210), wherein one of the two thin-film transistors (330) has a source electrode (323) connected to a cathode (211) of one of the two thin-film photodiodes (210), a gate electrode (321) connected to an odd-numbered control line (410), and a drain electrode (322) connected to a signal output line (450); wherein the other of the two thin-film transistors (320) has a source electrode (323) connected to a cathode (211) of the other of the two thin-film photodiodes (210), a gate electrode (321) connected to an even-numbered control line (420), and a drain electrode (322) connected to the signal output line (450); wherein the signal output line (450) is connected to a charge readout circuit (500), wherein the two anodes (212) of the two thin-film photodiodes (210) are connected to a common ground line (490) of the pixels (350); the charge readout circuit (500) converts a quantity of the charges into a voltage that is transferred to a charge difference collector; the charge difference collector is a differentiation circuit comprising a reference charge register (510) and a signal charge register (520); the charge readout circuit receives signals when the thin-film transistor (320, 330) is in the off and on states, which are stored in the reference charge register (510) and the signal charge register (520) respectively, and a signal difference between the reference charge register (510) and the signal charge register (520) is input to an analog-to-digital converter circuit to avoid the influence of slight differences of thin-film transistors (320, 330) and thin-film photodiodes (210) during manufacture on the signal detection. [2] The X-ray image sensor (1050) according to claim 1, wherein a row drive circuit (400) controls opening and closing of the thin film transistor (320, 330) and simultaneously controls signal storage and signal output of the reference charge register (510) and the signal charge register (520). [3] The X-ray image sensor (1050) according to claim 2, wherein the X-ray image sensor (1050) further comprises a multi-signal output selection switch (460), the multi-signal output selection switch (460) being controlled by a line drive circuit (400), wherein by switching the switch, charges on different pixels (350) are discharged into the same signal output line (450). [4] The X-ray image sensor (1050) according to claim 3, wherein the row drive circuit (400) is adhered to a glass substrate, the multi-signal output selection switch (460) is integrated into the row drive circuit (400), the row drive signal line (430) is fabricated to be connected to finger-shaped row drive electrodes (435) that receive input signals from the row drive circuit (400). [5] The X-ray image sensor (1050) according to claim 1, wherein the charge readout circuits (500) are divided into charge readout circuits (500) arranged to the left and right of the X-ray image sensor (1050), and wherein the charge readout circuits (500) on each side are connected to only half of a total number of pixel lines. [6] An X-ray image detector device (1000) comprising a scintillator (100) that converts X-rays into visible radiation and a data integration processing unit (900), the X-ray image detector device (1000) further comprising a plurality of the X-ray image sensors (1050) according to claim 1, the X-ray image sensors (1050) being arranged in a matrix arrangement, the scintillator (100) being arranged directly opposite an X-ray source, the plurality of X-ray image sensors (1050) arranged in a matrix arrangement being arranged on the back of the scintillator (100), and the data integration processing unit (900) being connected to the X-ray image sensors (1050);wherein the x-ray image detector device (1000) further comprises an x-ray dose sensor (700), and wherein the x-ray dose sensor (700) generates a feedback signal and the feedback signal is provided to the x-ray source; [7] The X-ray image detecting device according to claim 6, wherein the X-ray dose sensor (700) generates the feedback signal by an X-ray dose feedback output unit. [8] The X-ray image detector device (1000) according to claim 6, wherein the X-ray image detector device (1000) is activated the moment the X-ray dose sensor (700) starts to accumulate charges, and wherein the accumulation of pixel charges of the X-ray image detector device (1000) is stopped the moment the X-ray dose sensor (700) reaches dosage requirements. [9] The X-ray image detector device (1000) according to claim 6, characterized by in that the X-ray image detector device (1000) further comprises an anti-scatter grid, wherein the anti-scatter grid is arranged directly opposite the X-ray source, and wherein the scintillator (100) is arranged on the back of the anti-scatter grid. [10] The X-ray image detector device (1000) according to claim 9, characterized by that the anti-scatter grid is replaced by a virtual grid. [11] The X-ray image sensor (1050) according to claim 1, wherein the two thin film transistors (320, 330) included in each pixel (350) are arranged side by side in a same row.

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