WO2011010480A1 - 放射線画像撮影装置および放射線画像撮影システム - Google Patents
放射線画像撮影装置および放射線画像撮影システム Download PDFInfo
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- WO2011010480A1 WO2011010480A1 PCT/JP2010/051943 JP2010051943W WO2011010480A1 WO 2011010480 A1 WO2011010480 A1 WO 2011010480A1 JP 2010051943 W JP2010051943 W JP 2010051943W WO 2011010480 A1 WO2011010480 A1 WO 2011010480A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/30—Transforming light or analogous information into electric information
- H04N5/32—Transforming X-rays
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
- A61B6/42—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for detecting radiation specially adapted for radiation diagnosis
- A61B6/4208—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for detecting radiation specially adapted for radiation diagnosis characterised by using a particular type of detector
- A61B6/4233—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for detecting radiation specially adapted for radiation diagnosis characterised by using a particular type of detector using matrix detectors
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
- A61B6/44—Constructional features of apparatus for radiation diagnosis
- A61B6/4494—Means for identifying the diagnostic device
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
- H04N1/41—Bandwidth or redundancy reduction
Definitions
- the present invention relates to a radiographic image capturing apparatus and a radiographic image capturing system, and more particularly, to a radiographic image capturing apparatus that compresses and transfers image data and a radiographic image capturing system that receives the image data and restores the original image data.
- a so-called direct type radiographic imaging device that generates electric charges by a detection element in accordance with the dose of irradiated radiation such as X-rays and converts it into an electrical signal, or other radiation such as visible light with a scintillator or the like.
- Various so-called indirect radiographic imaging devices have been developed that convert charges to electromagnetic waves after being converted into electrical signals by generating electric charges with photoelectric conversion elements such as photodiodes in accordance with the energy of the converted and irradiated electromagnetic waves. Yes.
- the detection element in the direct type radiographic imaging apparatus and the photoelectric conversion element in the indirect type radiographic imaging apparatus are collectively referred to as a radiation detection element.
- This type of radiographic imaging device is known as an FPD (Flat Panel Detector) and has been conventionally formed integrally with a support base (or a bucky apparatus) (see, for example, Patent Document 1).
- FPD Full Panel Detector
- a portable radiographic imaging device in which an element or the like is housed in a housing has been developed and put into practical use (see, for example, Patent Documents 2 and 3).
- a plurality of radiation detection elements are arranged in a two-dimensional shape (matrix shape) to form a detection unit.
- the number of radiation detection elements (that is, the number of pixels) is Usually, the number of pixels is several million to several tens of millions of pixels or more. Therefore, if the image data read from each radiation detection element is transferred to the external device without being compressed, the transfer time becomes longer. Further, in a portable radiographic imaging apparatus with a built-in battery, when the transfer time of image data becomes long, the power consumed at the time of transfer increases, leading to battery consumption.
- the read image data is usually reversible compression (also referred to as lossless compression) or lossy compression (also referred to as lossy compression).
- the data is compressed by a data compression method and transferred to an external device such as a console or a server.
- the radiographic imaging device is used as a medical image imaging device that images a part of a body such as a patient's head, chest, and limbs as a subject and uses the acquired radiographic image as a medical image for diagnosis or the like.
- a data compression method for compressing image data in general, image data before compression and after restoration are compared with a lossy compression method in which a part of information included in the image data is lost by the compression. It is considered preferable to employ a lossless compression method in which compression is performed so that the image data completely matches.
- JP-A-9-73144 JP 2006-58124 A Japanese Patent Laid-Open No. 6-342099 JP 2000-275350 A JP 2005-287927 A
- e and f in FIG. 23 represent the compression rate Rc when the apparatus is directly and uniformly irradiated with radiation in the absence of a subject, and e is when the dose of irradiated radiation is small, f shows the case where the dose of the irradiated radiation is increased.
- the compression rate Rc of the obtained image data may deteriorate as the radiation dose applied to the radiographic imaging device increases.
- the compression ratio Rc is calculated as a value obtained by subtracting the data amount after compression from the data amount before compression and dividing the data amount by the data amount before compression. Therefore, the higher the compression rate Rc, the smaller the amount of data after compression. Further, the same Huffman code table is used for calculating the compression ratio Rc of a to f in FIG.
- the inventor of the present application can further improve the compression rate Rc of the image data acquired by the radiographic image capturing apparatus. We could find a reversible data compression method.
- the present invention has been made in view of the above points, and provides a radiographic imaging apparatus and a radiographic imaging system capable of improving the compression rate when compressing image data acquired by radiographic imaging.
- the purpose is to do.
- the radiographic imaging device of the present invention includes: A plurality of scanning lines and a plurality of signal lines arranged so as to intersect with each other; a plurality of radiation detecting elements arranged in a two-dimensional manner in each region partitioned by the plurality of scanning lines and the plurality of signal lines; A detector comprising: A readout circuit that reads out charges from the radiation detection elements through the signal lines, converts the charges into electrical signals for each of the radiation detection elements, and outputs them as image data; Compression means for compressing the image data for each radiation detection element; With The compression means performs compression processing on each image data output from a plurality of the radiation detection elements connected to the same signal line for each signal line.
- the radiographic imaging device of the present invention is A plurality of scanning lines and a plurality of signal lines arranged so as to intersect with each other; a plurality of radiation detecting elements arranged in a two-dimensional manner in each region partitioned by the plurality of scanning lines and the plurality of signal lines;
- a detector comprising: A readout circuit that reads out charges from the radiation detection elements through the signal lines, converts the charges into electrical signals for each of the radiation detection elements, and outputs them as image data; Compression means for compressing the image data for each radiation detection element; With The compression means calculates difference between the image data of adjacent radiation detection elements for each image data output from a plurality of the radiation detection elements connected to the same signal line, and creates difference data In addition, a compression process is performed on the difference data.
- the radiographic imaging device of the present invention is A plurality of scanning lines and a plurality of signal lines arranged so as to intersect with each other; a plurality of radiation detecting elements arranged in a two-dimensional manner in each region partitioned by the plurality of scanning lines and the plurality of signal lines;
- a detector comprising: A readout circuit that reads out charges from the radiation detection elements through the signal lines, converts the charges into electrical signals for each of the radiation detection elements, and outputs them as image data; Thinned data generating means for thinning out and extracting image data for each scanning line unit from the image data, Compression means for compressing the thinned data; With The compression means performs a compression process on the thinned data adjacent in the signal line direction or creates a difference data by calculating a difference for the thinned data adjacent in the signal line direction. And performing compression processing.
- the radiographic imaging system of the present invention is A radiographic imaging apparatus comprising transfer means for transferring the image data subjected to the compression process; A console that decompresses and restores the original image data of the image data that has been subjected to the compression process transferred from the radiographic imaging device; It is characterized by providing.
- the radiographic imaging system of the present invention is A radiographic imaging apparatus comprising transfer means for transferring the difference data subjected to the compression process; A console that decompresses the difference data that has been subjected to the compression process transferred from the radiographic imaging device into the original difference data, and restores the original image data based on the decompressed original difference data; , It is characterized by providing.
- the distribution of the image data and the difference data is widened and the compression ratio is lowered depending on the variation in the output characteristics of each readout circuit as in the conventional compression processing for the image data arranged in the scanning line direction and the difference data thereof. Therefore, it is possible to accurately improve the compression rate when compressing image data acquired by radiographic imaging and the difference data thereof.
- each image data read by the same readout circuit and the difference data thereof are distributed in a normal distribution, even if the radiation dose irradiated to the radiographic imaging device increases, compressed image data and In the difference data, a state in which a short code is assigned to data having a high appearance frequency is maintained. Therefore, it is possible to maintain a high compression rate regardless of the dose of radiation applied. Therefore, it is possible to compress the image data and the difference data at a high compression rate even in a shooting environment in which a blank portion is captured in an image.
- FIG. 2 is a cross-sectional view taken along line AA in FIG. It is a top view which shows the structure of the board
- FIG. 5 is a sectional view taken along line XX in FIG. 4. It is a side view explaining the board
- FIGS. 14A to 14C are diagrams for explaining how to create difference data between image data adjacent to each other in the signal line direction connected to the same signal line using one buffer register.
- FIG. 15A is a graph showing the distribution of difference data of image data output from each radiation detection element connected to the same scanning line when radiation is uniformly applied to the apparatus, and FIG. It is a graph which shows distribution of the difference data at the time of making the radiation dose large in FIG. 15 (A).
- FIG. 16A is a graph showing the distribution of difference data of image data output from each radiation detection element connected to the same signal line when the apparatus is uniformly irradiated with radiation, and FIG.
- the left bar graphs a to f represent the compression ratios when the difference data is compressed for the image data in the signal line direction under each condition
- the right bar graphs indicate the difference data for the image data arranged in the scan line direction under each condition.
- (B) It is a figure showing the state which collected the thinning data extracted. It is a figure showing the state which extracted and collected the remaining image data.
- the radiographic imaging device is a so-called indirect radiographic imaging device that includes a scintillator or the like and converts the irradiated radiation into electromagnetic waves of other wavelengths such as visible light to obtain an electrical signal.
- the present invention can also be applied to a direct radiographic imaging apparatus.
- the radiographic image capturing apparatus is portable will be described, the present invention is also applicable to a radiographic image capturing apparatus formed integrally with a support base or the like.
- FIG. 1 is an external perspective view of the radiographic image capturing apparatus according to the present embodiment
- FIG. 2 is a cross-sectional view taken along the line AA in FIG.
- the radiation image capturing apparatus 1 according to the present embodiment is configured by housing a scintillator 3, a substrate 4, and the like in a housing 2.
- the housing 2 is formed of a material such as a carbon plate or plastic that transmits at least the radiation incident surface R. 1 and 2 show a case in which the housing 2 is a so-called lunch box type formed by the frame plate 2A and the back plate 2B. However, the housing 2 is integrally formed in a rectangular tube shape. It is also possible to use a so-called monocoque type.
- the side surface of the housing 2 is opened and closed for replacement of a power switch 36, an indicator 37 composed of LEDs and the like, and a battery 41 (not shown) (see FIG. 7 described later).
- a possible lid member 38 and the like are arranged.
- an antenna device 39 is embedded in the side surface of the lid member 38 as transfer means for wirelessly transferring image data or the like to an external device such as a console 58 (see FIG. 18) described later. It is. It is also possible to transfer the image data or the like to an external device in a wired manner.
- a connection terminal or the like for connecting by inserting a cable or the like is used as radiation. It is provided on the side surface of the image capturing apparatus 1 or the like.
- a base 31 is disposed inside the housing 2 via a thin lead plate or the like (not shown) on the lower side of the substrate 4.
- the disposed PCB substrate 33, the buffer member 34, and the like are attached.
- a glass substrate 35 for protecting the substrate 4 and the radiation incident surface R of the scintillator 3 is disposed.
- the scintillator 3 is affixed to a detection part P (described later) of the substrate 4.
- the scintillator 3 is, for example, a phosphor whose main component is converted into an electromagnetic wave having a wavelength of 300 to 800 nm, that is, an electromagnetic wave centered on visible light when it receives radiation, and that is output.
- the substrate 4 is formed of a glass substrate. As shown in FIG. 3, a plurality of scanning lines 5 and a plurality of signal lines are provided on a surface 4 a of the substrate 4 facing the scintillator 3. 6 are arranged so as to cross each other. In each small region r defined by the plurality of scanning lines 5 and the plurality of signal lines 6 on the surface 4 a of the substrate 4, radiation detection elements 7 are respectively provided.
- the region is a detection unit P.
- a photodiode is used as the radiation detection element 7, but other than this, for example, a phototransistor or the like can also be used.
- Each radiation detection element 7 is connected to the source electrode 8s of the TFT 8 serving as a switch means, as shown in the enlarged views of FIGS.
- the drain electrode 8 d of the TFT 8 is connected to the signal line 6.
- the TFT 8 is turned on when a turn-on voltage is applied to the connected scanning line 5 by the scanning drive means 15 described later and applied to the gate electrode 8g, and is generated and accumulated in the radiation detection element 7. The charged electric charge is discharged to the signal line 6. Further, the TFT 8 is turned off when the off voltage is applied to the connected scanning line 5 and the off voltage is applied to the gate electrode 8g, and the emission of the charge from the radiation detecting element 7 to the signal line 6 is stopped. The charges generated in the radiation detection element 7 are held and accumulated in the radiation detection element 7.
- FIG. 5 is a sectional view taken along line XX in FIG.
- a gate electrode 8g of a TFT 8 made of Al, Cr or the like is formed on the surface 4a of the substrate 4 so as to be integrally laminated with the scanning line 5, and silicon nitride (laminated on the gate electrode 8g and the surface 4a).
- An upper portion of the gate electrode 8g on the gate insulating layer 81 made of SiN x ) or the like is connected to the first electrode 74 of the radiation detection element 7 via a semiconductor layer 82 made of hydrogenated amorphous silicon (a-Si) or the like.
- the formed source electrode 8s and the drain electrode 8d formed integrally with the signal line 6 are laminated.
- the source electrode 8s and the drain electrode 8d are divided by a first passivation layer 83 made of silicon nitride (SiN x ) or the like, and the first passivation layer 83 covers both electrodes 8s and 8d from above.
- ohmic contact layers 84a and 84b formed in an n-type by doping hydrogenated amorphous silicon with a group VI element are stacked between the semiconductor layer 82 and the source electrode 8s and the drain electrode 8d, respectively.
- the TFT 8 is formed as described above.
- an auxiliary electrode 72 is formed by laminating Al, Cr, or the like on the insulating layer 71 formed integrally with the gate insulating layer 81 on the surface 4 a of the substrate 4.
- a first electrode 74 made of Al, Cr, Mo or the like is laminated on the auxiliary electrode 72 with an insulating layer 73 formed integrally with the first passivation layer 83 interposed therebetween.
- the first electrode 74 is connected to the source electrode 8 s of the TFT 8 through the hole H formed in the first passivation layer 83.
- a p layer 77 formed by doping a group III element into silicon and forming a p-type layer is formed by laminating sequentially from below.
- the electromagnetic wave When radiation enters from the radiation incident surface R of the housing 2 of the radiographic imaging apparatus 1 and is converted into an electromagnetic wave such as visible light by the scintillator 3, and the converted electromagnetic wave is irradiated from above in the figure, the electromagnetic wave is detected by radiation.
- the electron hole pair is generated in the i layer 76 by reaching the i layer 76 of the element 7. In this way, the radiation detection element 7 converts the electromagnetic waves irradiated from the scintillator 3 into electric charges.
- a second electrode 78 made of a transparent electrode such as ITO is laminated and formed so that the irradiated electromagnetic wave reaches the i layer 76 and the like.
- the radiation detection element 7 is formed as described above. The order of stacking the p layer 77, the i layer 76, and the n layer 75 may be reversed. Further, in the present embodiment, a case where a so-called pin-type radiation detection element formed by sequentially stacking the p layer 77, the i layer 76, and the n layer 75 as described above is used as the radiation detection element 7. However, it is not limited to this.
- a bias line 9 for applying a bias voltage to the radiation detection element 7 is connected to the upper surface of the second electrode 78 of the radiation detection element 7 via the second electrode 78.
- the second electrode 78 and the bias line 9 of the radiation detection element 7, the first electrode 74 extended to the TFT 8 side, the first passivation layer 83 of the TFT 8, that is, the upper surfaces of the radiation detection element 7 and the TFT 8 are A second passivation layer 79 made of silicon nitride (SiN x ) or the like is covered from above.
- one bias line 9 is connected to a plurality of radiation detection elements 7 arranged in rows, and each bias line 9 is connected to a signal line 6. Are arranged in parallel with each other. Further, each bias line 9 is bound to the connection 10 at a position outside the detection portion P of the substrate 4.
- each scanning line 5, each signal line 6, and connection 10 of the bias line 9 are input / output terminals (also referred to as pads) provided near the edge of the substrate 4. 11 is connected.
- each input / output terminal 11 has a COF (ChipCOn Film) 12 in which a chip such as a gate IC 12 a constituting a gate driver 15 b of the scanning drive means 15 described later is incorporated. They are connected via an anisotropic conductive adhesive material 13 such as a film (Anisotropic Conductive Film) or an anisotropic conductive paste (Anisotropic Conductive Paste).
- the COF 12 is routed to the back surface 4b side of the substrate 4 and connected to the PCB substrate 33 described above on the back surface 4b side.
- substrate 4 part of the radiographic imaging apparatus 1 is formed.
- illustration of the electronic component 32 and the like is omitted.
- FIG. 7 is a block diagram illustrating an equivalent circuit of the radiographic imaging apparatus 1 according to the present embodiment
- FIG. 8 is a block diagram illustrating an equivalent circuit for one pixel constituting the detection unit P.
- each radiation detection element 7 of the detection unit P of the substrate 4 has the bias line 9 connected to the second electrode 78, and each bias line 9 is bound to the connection 10 to the bias power supply 14. It is connected.
- the bias power supply 14 applies a bias voltage to the second electrode 78 of each radiation detection element 7 via the connection 10 and each bias line 9.
- the bias power source 14 is connected to a control unit 22 described later, and the control unit 22 controls a bias voltage applied to each radiation detection element 7 from the bias power source 14.
- the current detection means 43 for detecting the amount of current flowing through the connection 10 is provided in the connection 10 of the bias line 9.
- the current detection means 43 can detect the start and end of radiation irradiation by detecting the increase or decrease of the current flowing through the connection 10. In the present invention, the current detection means 43 is not necessarily provided.
- the bias line 9 is connected via the second electrode 78 to the p-layer 77 side (see FIG. 5) of the radiation detection element 7.
- the bias power supply 14 supplies a voltage equal to or lower than a voltage applied to the second electrode 78 of the radiation detection element 7 via the bias line 9 as a bias voltage on the first electrode 74 side of the radiation detection element 7 (that is, a so-called reverse bias voltage). Is applied.
- the first electrode 74 of each radiation detection element 7 is connected to the source electrode 8s of the TFT 8 (indicated as S in FIGS. 7 and 8), and the gate electrode 8g of each TFT 8 (FIGS. 7 and 8). Are respectively connected to the lines L1 to Lx of the scanning line 5 extending from a gate driver 15b of the scanning driving means 15 described later. Further, the drain electrode 8 d (denoted as D in FIGS. 7 and 8) of each TFT 8 is connected to each signal line 6.
- the scanning drive unit 15 includes a power supply circuit 15a that supplies an on voltage and an off voltage to the gate driver 15b, and a voltage applied to each of the lines L1 to Lx of the scanning line 5 between the on voltage and the off voltage.
- a gate driver 15b that switches between the on state and the off state of each TFT 8 is provided.
- the gate driver 15b is formed by arranging a plurality of the gate ICs 12a described above.
- Each signal line 6 is connected to each readout circuit 17 formed in the readout IC 16. Note that the readout IC 16 is provided with one readout circuit 17 for each signal line 6.
- the readout circuit 17 includes an amplification circuit 18, a correlated double sampling circuit 19, an analog multiplexer 21, and an A / D converter 20. 7 and 8, the correlated double sampling circuit 19 is represented as CDS. In FIG. 8, the analog multiplexer 21 is omitted.
- the amplifier circuit 18 is configured by a charge amplifier circuit, and is configured by connecting a capacitor 18b and a charge reset switch 18c in parallel to the operational amplifier 18a and the operational amplifier 18a, respectively.
- a power supply unit 18 d for supplying power to the amplifier circuit 18 is connected to the amplifier circuit 18.
- the signal line 6 is connected to the inverting input terminal on the input side of the operational amplifier 18 a of the amplifier circuit 18, and the reference potential V 0 is applied to the non-inverting input terminal on the input side of the amplifier circuit 18. ing.
- the reference potential V 0 is set to an appropriate value, and in this embodiment, for example, 0 [V] is applied.
- the charge reset switch 18c of the amplifier circuit 18 is connected to the control means 22 described later, and is turned on / off by the control means 22.
- the image data is read from each radiation detection element 7, when the charge reset switch 18c is turned off and the TFT 8 of the radiation detection element 7 is turned on (that is, the scanning line 5 is applied to the gate electrode 8g of the TFT 8).
- the electric charge released from the radiation detection element 7 flows into the capacitor 18b and is accumulated, and a voltage value corresponding to the accumulated electric charge is output from the operational amplifier 18a. Output from the side.
- the amplification circuit 18 outputs a voltage value according to the amount of charge output from each radiation detection element 7 and converts the charge voltage.
- the charge reset switch 18c When the charge reset switch 18c is turned on, the input side and the output side of the amplifier circuit 18 are short-circuited, and the charge accumulated in the capacitor 18b is discharged to reset the amplifier circuit 18. ing.
- the amplifier circuit 18 may be configured to output a current in accordance with the charge output from the radiation detection element 7.
- the charge is read from each radiation detection element 7, and the voltage value that is output after being subjected to charge-voltage conversion by the amplifier circuit 18 is sampled by the correlated double sampling circuit 19. It is processed and output downstream as image data.
- the image data of each radiation detection element 7 output from the correlated double sampling circuit 19 is transmitted to the analog multiplexer 21 (see FIG. 7), and is sequentially transmitted from the analog multiplexer 21 to the A / D converter 20. Then, the A / D converter 20 sequentially converts the image data into digital values, which are output to the storage means 40 and sequentially stored.
- the lines L1 to Lx of the scanning line 5 to which the on-voltage is applied are sequentially switched, and each of the above-described ones is performed.
- a process for reading image data from the radiation detection element 7 is performed.
- 128 signal lines 6 are processed by one readout IC 16. That is, one read IC 16 corresponds to each signal line 6 with 128 read circuits 17 (that is, amplifier circuit 18 and correlated double sampling circuit 19 etc.), one analog multiplexer 21, and one A / D. It is formed by a converter 20 or the like.
- the number of readout circuits 17 formed in one readout IC 16 that is, the number of signal lines 6 connected to one readout IC 16 is 128, and the total number of signal lines 6 is 2048.
- the present invention is not limited to this case.
- To (1,2048) are simultaneously read out and sent to the reading ICs 16 in parallel.
- each read circuit 17 (not shown in FIG. 9) of each read IC 16 performs charge-voltage conversion and the like, and each of the 128 image data transmitted in parallel is converted into each analog multiplexer 21 (in each read IC 16).
- the image data is serially transferred to the A / D converter 20 (not shown) sequentially and digitized image data is temporarily stored in the buffer memory 45 from the A / D converter 20.
- image data corresponding to each radiation detection element (x, y) is represented as D (x, y)
- D (1, 1), D (1, 129), D ( 1, 257),..., D (1, 1921) are transmitted and stored in the buffer memory 45, and then D (1, 2), D (1, 130), D (1, 258). ,..., D (1, 1922) are transmitted and stored in the buffer memory 45.
- the image data D (1,1) to D (1,2048) from the radiation detection elements (1,1) to (1,2048) connected to the line L1 of the scanning line 5 is stored in the buffer memory 45.
- the image data D are rearranged in the order of image data D (1,1), D (1,2), D (1,3), D (1,4),. 40 are sequentially transmitted and stored.
- each image data D (1,1) to D (1,2048) from each radiation detection element (1,1) to (1,2048) connected to the line L1 of the scanning line 5 is completed.
- the line of the scanning line 5 to which the ON voltage is applied is subsequently switched to L2.
- the image data D (2,1) to D (2,2048) are transmitted to the buffer memory 45 for each readout IC 16 and rearranged, and then sequentially transmitted to the storage means 40 and stored.
- the reading process and the storing process in the storage unit 40 are sequentially repeated for each of the lines L1 to Lx of the scanning line 5 so that the reading process of the image data D from all the radiation detection elements 7 is performed. It has become.
- the rearrangement process of the image data D is normally performed by converting the image data D into D (1,1), D (1,1) regardless of the external device (not shown) that transfers the image data D. 2), D (1,3), D (1,4),... Can be dealt with by transferring them in this order. Therefore, the image data D is generally used at the stage of storing the image data D in the storage means 40. This is a process for rearranging and storing D in the above order.
- the image data D can be rearranged according to the determined order.
- each image data D is preliminarily output from the radiation imaging apparatus 1 to the external device, for example, in the order of output from each readout IC 16, D (1, 1), D (1, 129),..., D (1, 1921), If it is determined that the data is transferred in the order of D (1,2), D (1,130),..., D (1,1922),. It is also possible to send the data directly to the storage means 40 and save them without going through 45.
- the image data D is rearranged when each image data D is read from the storage means 40, not when the image data D is stored in the storage means 40. It is also possible to configure so that
- each image data D read from each radiation detection element 7 as described above is temporarily stored in the storage unit 40 and then transferred from the radiation image capturing apparatus 1 to an external device (not shown).
- each image data D read from each radiation detection element 7 is not stored in the storage unit 40 or separately from the storage in the storage unit 40. It is also possible to configure so that each image data D is directly transferred after being subjected to compression processing.
- the control means 22 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a RAM (Random Access Memory), an input / output interface connected to the bus, an FPGA (Field Programmable Gate Array), and the like. Has been. It may be configured by a dedicated control circuit. And the control means 22 controls operation
- a DRAM Dynamic RAM
- the above-described antenna device 39 is connected to the control unit 22, and each member such as the detection unit P, the scanning drive unit 15, the readout circuit 17, the storage unit 40, the bias power supply 14, and the like.
- a battery 41 for supplying electric power is connected.
- the battery 41 is provided with a connection terminal 42 for charging the battery 41 by supplying power to the battery 41 from a charging device (not shown) such as a cradle.
- control means 22 controls the bias power supply 14 to set a bias voltage to be applied to each radiation detection element 7 from the bias power supply 14, or the charge reset switch 18 c of the amplification circuit 18 of the readout circuit 17.
- Various processes such as on / off control and transmission of a pulse signal to the correlated double sampling circuit 19 to control on / off of the sample hold function are executed.
- control means 22 applies each of the scanning driving means 15 to the scanning driving means 15 at the time of reset processing of each radiation detecting element 7 or at the time of reading the image data D from each radiation detecting element 7 after radiographic imaging.
- a pulse signal for switching the voltage applied to the gate electrode 8g of each TFT 8 between the ON voltage and the OFF voltage via the scanning line 5 is transmitted.
- a register unit 44 having at least two buffer registers is connected to the control unit 22, and the compression unit and the thinned data generation unit of the present invention are connected by the control unit 22 and the register unit 44. Is formed.
- the register unit 44 is provided integrally with the FPGA constituting the control means 22. Further, when the control means 22 is configured by a computer including a CPU or the like, it is also possible to configure so that an existing register in the computer is used as the register unit 44. Furthermore, in this embodiment, the register unit 44 is provided with two buffer registers. However, as will be described later, it may be configured to provide one buffer register, and three or more buffer registers may be provided. You may comprise so that it may provide.
- the wireless method is not saved in the storage unit 40 as it is and is transmitted from the antenna device 39.
- each image data D is D (n, 1), D (n, 2), D (n, 3), D (n, 4),...
- the image data D (n, 1), D (n, 2) of each line Ln of the scanning line 5 from the storage means 40. , D (n, 3), D (n, 4),... Is read each time the image data D is compressed. That is, the compression processing of the image data D is performed on the image data D arranged in the scanning line direction (that is, the image data D output from the radiation detection elements 7 connected to the same scanning line 5). In addition, the compression processing of the image data D is performed for each of the lines L1 to Lx of the scanning line 5. Note that the arrow below each image data D in FIG. 10 indicates the direction in which compression processing is performed, that is, the scanning line direction in this case.
- the image data D (n, 1), D (n, 2), D (n, 2), D (n, 3), D (n, 4),... are each image data D in the signal line direction arranged so as to be orthogonal to the scanning line 5, that is, each radiation detecting element connected to the same signal line 6.
- the image data D output from the image data D is compressed, and the image data D is compressed for each signal line 6.
- the vertical arrow on each image data D in FIG. 11 indicates the direction in which compression processing is performed, that is, the signal line direction in this case.
- the compression processing of the image data D it is possible to configure the image data D in the signal line direction to be compressed as it is.
- the image data D of this embodiment is finely divided into gradations comparable to an analog image using a conventional silver salt film, the dynamic range of data values that each image data D can take (dynamic range) ) Becomes very large.
- the image data D when the image data D has 30,000 gradations, the image data D can take data values between 0 and 30000. Therefore, for example, when the compression method of the image data D such as Huffman coding is used as described later, the compression rate Rc of the image data D may not necessarily be a good value.
- a method of compression processing for the difference data created by calculating the difference between the adjacent image data D is employed, but as described above, in the present embodiment.
- Each image data D in the signal line direction that is, each image data D (1, m), D (2, m), D (3, m) output from each radiation detecting element connected to the same signal line 6 , D (4, m),... (See FIG. 11)
- the difference between adjacent image data D is calculated to create difference data ⁇ D
- the difference data ⁇ D is compressed. It is configured.
- the register unit 44 is provided with at least two buffer registers 44a and 44b, and the compressed difference data ⁇ D is transmitted to the antenna device 39.
- a buffer memory 44c is provided for temporarily storing the data before transferring the data to the external device via the.
- control means 22 was read from each radiation detection element 7 connected to each line Ln, Ln + 1 of the adjacent scanning line 5 from the memory
- Each image data D (n, 1), D (n, 2), D (n, 3), D (n, 4),..., D (n + 1, 1), D (n + 1, 1) arranged in the scanning line direction. ), D (n + 1,3), D (n + 1,4),... Are read out and temporarily stored in the buffer registers 44a and 44b, respectively.
- the difference ⁇ D between the image data at the same address in the buffer registers 44a and 44b is the image data D output from each radiation detection element connected to the same signal line 6, the difference ⁇ D between the image data at the same address. (That is, ⁇ D (n + 1,1), ⁇ D (n + 1,2), ⁇ D (n + 1,3), ⁇ D (n + 1,4),...) Is calculated in the direction of the signal line connected to the same signal line 6 Difference data ⁇ D between the image data D of the adjacent radiation detection elements 7 is created.
- the control means 22 is the difference data of each image data D arranged in the scanning line direction read from each radiation detection element 7 connected to each line Ln, Ln + 1 of the adjacent scanning line 5.
- the image data D (n + 1, 1), D (n + 1, 2), D (n + 1, 3), D (n + 1, 4),... are moved from the buffer register 44b to the buffer register 44a, and are emptied.
- the difference data ⁇ D (n + 2, 1), ⁇ D (n + 2, 2),... Is calculated
- the image data D (n + 2, 1), D (n + 2, 2),... Are transferred from the buffer register 44b to the buffer register 44a.
- the image data D (n + 3, 1), D (n + 3, 2),... are accumulated in the buffer register 44b.
- the process of calculating the difference ⁇ D between the image data D at the same address in the buffer registers 44a and 44b while transferring each image data D from the buffer register 44b to the buffer register 44a is repeated to sequentially create the difference data ⁇ D. It has come to do.
- the image data D (1,1) and D (1,2) arranged in the scanning line direction read from the radiation detecting elements 7 connected to the line L1 of the first scanning line 5 are arranged.
- Data used as a reference for calculation is required. Therefore, in this embodiment, preset reference data Dc (1), Dc (2), Dc (3), Dc (4),... are stored in advance in a memory such as a ROM.
- the control means 22 calculates each difference data ⁇ D (1,1), ⁇ D (1,2), ⁇ D (1,3), ⁇ D (1,4),... As shown in FIG. As described above, the reference data Dc (1), Dc (2),... Read from the memory are accumulated in the buffer register 44a, and from each radiation detection element 7 connected to the line L1 of the scanning line 5 read from the storage means 40. The read image data D (1,1), D (1,2),... Arranged in the scanning line direction are accumulated in the buffer register 44b, and the difference ⁇ D is obtained as the difference data ⁇ D (1,1), ⁇ D. (1, 2),... Are calculated.
- the respective values of the reference data Dc (1), Dc (2),... May be set to the same value, or may be set to different values from each other, and are set appropriately in advance. .
- the difference data ⁇ D is generated by calculating the difference between the image data D adjacent in the signal line direction similar to the above. Is possible.
- the image data D (n, 1), D (n, 2), D (n, 3), D (n, 4),... Arranged in the scanning line direction of the line Ln of the scanning line 5 are stored in the buffer register 44a. It is assumed that it has been accumulated.
- the control means 22 makes the image data D (n + 1, 1), D (n + 1, 2), D (n + 1, 3), D (n + 1) arranged in the scanning line direction of the line Ln + 1 of the adjacent scanning line 5. , 4),... Are sequentially read from the storage means 40, and the corresponding image data D (n, 1), D (n, 2), D (n, 3), D (n, 4),. In this case, the difference data ⁇ D between the corresponding image data D is calculated and replaced.
- the differential data ⁇ D created in this way is configured to be compressed.
- a compression method is used.
- the Huffman coding method is adopted as the lossless compression method.
- the compression method is not necessarily required by the Huffman coding, and other lossless compression methods or It is also possible to configure so that the differential data ⁇ D (or image data D) is compressed using an irreversible compression method.
- a table of Huffman codes created in advance for compression processing is stored in a memory such as a ROM in advance.
- the constituting control means 22 is configured to perform Huffman coding of the difference data ⁇ D with reference to this table during the compression process.
- the control means 22 every time the difference data ⁇ D is created as described above, the control means 22 refers to the Huffman code table and assigns a corresponding Huffman code Hc to the difference data ⁇ D. Yes. That is, each Huffman code Hc corresponds to each compressed difference data ⁇ D. In data compression by Huffman coding, as is well known, data having a higher appearance frequency is assigned a shorter Huffman code Hc.
- the control means 22 temporarily stores each Huffman code Hc assigned to each difference data ⁇ D in the buffer memory 44c (see FIG. 12), and sequentially transfers it to the external device via the antenna device 39. Yes.
- the external device to which the difference data ⁇ D is transferred from the radiation image capturing apparatus 1 also includes the same Huffman code Hc table, and the external device refers to the table during the decompression process.
- the compressed differential data ⁇ D that has been transferred is configured to be decompressed. Further, as described above, it is possible to compress the image data D in the signal line direction as it is without creating the difference data ⁇ D. In such a configuration, radiographic imaging is possible.
- the apparatus 1 and the external apparatus are configured to have a table of Huffman codes Hc for compressing / decompressing image data D common to the apparatus 1 and the external apparatus.
- the Huffman code Hc table may be configured to include only one type of table, but may be configured to include a plurality of types of tables, and the control unit 22 selects and references the tables. It is also possible to configure as described above. For example, when the radiographic imaging device 1 is used as a medical image imaging device as described above, depending on the imaging region (chest, skull, lumbar spine, etc.) of the patient's body as the subject and the imaging direction (front, side, etc.), There are many cases where imaging conditions such as radiation dose and irradiation time can be changed.
- a plurality of types of tables of Huffman codes Hc for compression processing are provided in advance for each imaging condition including the imaging part and imaging direction of the patient's body, which is the subject, and the control unit 22 sets the imaging condition to the set imaging condition. If the table is selected according to the selected table, and the Huffman coding of the difference data ⁇ D (or image data D) is performed with reference to the selected table, the difference data ⁇ D (or image data D) is compressed.
- the compression rate Rc of the difference data ⁇ D (or image data D) can be further improved in accordance with the shooting conditions.
- imaging order information for specifying an imaging region or an imaging direction of a patient's body, which is a subject, is often created in advance.
- Information of imaging conditions including information, imaging region, imaging direction, etc. is transferred from the external device to the radiographic imaging apparatus 1, or an operator such as a radiographer sends imaging order information and imaging condition information to the radiographic imaging apparatus 1. By inputting, an imaging condition is set for the radiation image capturing apparatus 1.
- the radiographic image capturing apparatus 1 and the external apparatus are preliminarily associated with the radiographic image capturing apparatus 1 and the external apparatus in advance in association with the imaging condition and the Huffman code Hc table.
- it is possible to configure a table to be used by specifying a table to be used based on the imaging region and the imaging direction in the imaging order information.
- the information on the number of the used table is transferred together, and the external apparatus uses the number information etc. It is also possible to configure to decompress using a specified table.
- a table of Huffman codes Hc suitable for the radiographic image capturing conditions is transmitted from the external device to the radiographic image capturing device 1 to be stored or rewritten, and the control means 22 is transmitted. It is also possible to perform compression processing by referring to the table of the Huffman code Hc and performing Huffman encoding of the image data D and the difference data ⁇ D.
- each radiation detection element 7 connected to the line Ln of the same scanning line 5 is used.
- the radiographic imaging device 1 When the radiation is uniformly irradiated, the radiation detection elements (n, 1), (n, 2), (n, 3), (n, 4),... Connected to the line Ln of the same scanning line 5.
- each radiation detection element (n, 1), (n, 2), (n, 3), (n, 4),... Connected to the line Ln of the same scanning line 5.
- the difference data ⁇ D of the image data D (n, 1), D (n, 2), D (n, 3), D (n, 4),... Distributed in a relatively wide range. .
- the distribution of the difference data ⁇ D of the image data D output from each radiation detection element 7 connected to the line Ln of the same scanning line 5 is shown in FIG.
- the main reason for the distribution is that the output characteristics of the readout circuits 17 that read out the image data D from each radiation detection element 7 are different for each readout circuit 17, and the output characteristics of the readout circuits 17 vary. It is thought that there is.
- each of the 2048 readout circuits 17 formed in each readout IC 16 the charge-voltage conversion characteristics of the amplifier circuit 18 and the sampling of the correlated double sampling circuit 19 are performed.
- the output characteristics of the readout circuit 17 in which characteristics and the like are integrated are different. For this reason, even if the image data sent from each radiation detection element 7 to each readout circuit 17 has the same value, it is considered that the image data D output after charge-voltage conversion in each readout circuit 17 has a different value. .
- the difference that occurs in the image data D due to the difference in the output characteristics of the readout circuits 17 is, for example, the image data D (to be exact, offset from the image data D after the transfer to the external device and in the image correction process). This is eliminated or reduced by adjusting the gain correction value for each readout circuit 17 that multiplies the value obtained by subtracting the value.
- the difference data ⁇ D other than the difference data ⁇ D in the part of ⁇ D ⁇ ⁇ ( ⁇ ⁇ 0) to which the most frequently occurring frequency F and the shortest Huffman code Hc are assigned.
- the appearance frequency F is relatively large.
- the intensity of the electromagnetic wave that is converted by the scintillator 3 and applied to each radiation detection element 7 increases.
- the value of the data D itself increases and the value of the difference data ⁇ D also increases.
- the distribution as originally shown in FIG. 15 (A) is a distribution that spreads toward the plus side and the minus side as shown in FIG. 15 (B) when the dose of radiation irradiated to the radiation image capturing apparatus 1 is increased. It becomes. Therefore, the range of the difference data ⁇ D other than the difference data ⁇ D to which the shortest Huffman code Hc is assigned and the difference data ⁇ D having a relatively high appearance frequency F is widened, and the difference data ⁇ D to which the longer Huffman code Hc is assigned is expanded. Since the number increases, it is considered that the compression rate of the difference data ⁇ D is further deteriorated.
- the radiation image capturing apparatus 1 is irradiated as compared to f in FIG. 23 which represents the compression rate Rc when the radiation image capturing apparatus 1 is directly and uniformly irradiated with weak radiation in the absence of a subject. It can also be seen from the fact that the compression rate Rc is further deteriorated in the case of e in FIG.
- each radiation detection element (1, m), (2, m) connected to the same signal line 6 arranged so as to be orthogonal to each line Ln of the same scanning line 5 instead.
- (3, m), (4, m),... When paying attention to (3, m), (4, m),..., When the radiation of the same dose is irradiated to each of the radiation detection elements 7 or the electromagnetic waves of the same intensity converted by the scintillator 3 are irradiated,
- the distribution of the difference data ⁇ D is not affected by the variation in the output characteristics of the readout circuits 17 as described above. Therefore, in this case, it is considered that only the influence of the manufacturing variation of each radiation detection element 7 is reflected, and the distribution of the difference data ⁇ D becomes a normal distribution as shown in FIG.
- the appearance frequency F of the difference data ⁇ D is reduced. Therefore, when the Huffman code Hc is assigned to each differential data ⁇ D having the distribution shown in FIG. 16A, the number of the differential data ⁇ D to which the short Huffman code Hc is assigned increases, and the compression rate Rc of the differential data ⁇ D. Will improve.
- the Huffman code Hc is assigned to each differential data ⁇ D having the distribution shown in FIG. 16B, the number of the differential data ⁇ D to which the short Huffman code Hc is assigned increases, and the compression rate of the differential data ⁇ D is increased. Even if the dose of radiation applied to the radiation imaging apparatus 1 is increased, it is considered that the state in which the compression rate Rc of the difference data ⁇ D is high is maintained.
- the compression processing of the image data D and the difference data ⁇ D of the present invention that is, each image data D in the signal line direction (that is, each image data D output from each radiation detection element connected to the same signal line 6).
- the difference data ⁇ D, and the compression process shown in FIGS. 11 to 14 is a process for realizing this.
- each compression rate Rc is improved in comparison with the compression rate Rc in each case of a to f in FIG.
- the bar graph on the right side in each case of a to f in FIG. 17 is the same graph as the bar graph of the compression ratio Rc in each case of a to f in FIG.
- results of the compression processing of each image data D and each difference data ⁇ D according to the present invention shown in the left bar graph in each case of a to f in FIG. 17 are the conventional scanning line directions showing the results on the right side in each case.
- This is an experimental result using the same table as the Huffman code Hc table used in the compression process for the image data D and the difference data ⁇ D thereof.
- each image data D and each difference data ⁇ D in the signal line direction As described above, when the compression processing of each image data D and each difference data ⁇ D in the signal line direction according to the present invention is used, even when the same Huffman code Hc table is used, the output characteristics of each readout circuit 17 vary. It is possible to accurately improve the compression rate Rc when compressing each image data D acquired by radiographic imaging and its difference data ⁇ D by eliminating the influence.
- a Huffman code Hc table suitable for performing compression processing on each image data D in the signal line direction and its difference data ⁇ D as in the present invention is provided. If it is appropriately created and compression processing is performed using it, the compression rate Rc can be further improved. At that time, if the table of the Huffman code Hc is appropriately created for each photographing condition including the photographing part and photographing direction of the patient's body as the subject, the compression ratio Rc can be further improved under each photographing condition. Can be expected.
- the characteristics of the compression processing of each image data D and each difference data ⁇ D according to the present invention are as described above in any case of a to f in FIG.
- the compression rate Rc of the image data D in the signal line direction and the compression process of the difference data ⁇ D is higher than the compression process of the image data D and the difference data ⁇ D arranged in the conventional scan line direction. It is in.
- the radiation image capturing apparatus 1 is irradiated with only weak radiation that has passed through the subject (see a and d in the figure), or a radiographic image.
- the difference data ⁇ D as shown in FIG. 15A is also obtained in the conventional compression processing of the image data D and the difference data ⁇ D. Since the range of the distribution of N is relatively narrow, the number of difference data ⁇ D to which the long Huffman code Hc is assigned is reduced and the compression rate Rc is increased. However, each image data D and each difference data in the signal line direction according to the present invention. In the compression process of ⁇ D, the compression rate Rc is higher than that.
- each image data D and each difference data ⁇ D in the signal line direction does not reflect the influence of the variation in the output characteristics of each readout circuit 17, and each radiation detection element 7. It is thought that the effect that reflects only the influence of manufacturing variation of the present has appeared.
- each image data D and each difference data ⁇ D arranged in the scanning line direction the influence of the variation in the output characteristics of each readout circuit 17 is reflected in addition to the influence of the manufacturing variation of each radiation detection element 7.
- the compression processing of each image data D and each difference data ⁇ D in the signal line direction according to the present invention affects the variation in output characteristics of each readout circuit 17 as described above. Instead, only the influence of the manufacturing variation of each radiation detection element 7 is reflected (see FIG. 16A).
- each image data D and each difference data ⁇ D As can be seen from a comparison between FIG. 15A and FIG. 16A, in the compression processing of each image data D and each difference data ⁇ D according to the present invention, the output characteristics of each readout circuit 17 vary. It is considered that the compression ratio Rc is high because the range of the difference data ⁇ D is narrowed and the number of the difference data ⁇ D to which the long Huffman code Hc is assigned becomes smaller.
- Another feature of the compression processing of each image data D and each difference data ⁇ D according to the present invention is radiation applied to the radiographic image capturing apparatus 1 as clearly shown in the results of e and f of FIG. Even if the dose increases, the compression rate Rc is maintained at a high level. That is, in the compression processing of each image data D and each difference data ⁇ D according to the present invention, a high compression rate Rc is maintained regardless of the dose of radiation irradiated or independent of the dose of radiation.
- the important effect associated therewith is that, for example, as shown in FIGS. 17c and 17d, it is not necessary to limit the radiation irradiation range as in photographing the lumbar side surface or the like (see d in FIG. 17).
- the compression ratio Rc is almost the same regardless of whether or not so-called unexposed portions where the radiation is directly applied to the surrounding portions such as the lumbar portion are eliminated or not. In other words, a high compression rate Rc is maintained.
- the subject In the conventional compression processing for the image data D arranged in the scanning line direction and the difference data ⁇ D, as shown in e and f of FIG. 23 (bar graphs on the right side of e and f of FIG. 17), the subject is not interposed.
- the compression rate Rc of the difference data ⁇ D decreased as the radiation dose directly applied to the radiation image capturing apparatus 1 increased. Then, under the imaging conditions in which the radiation missing part is photographed in the peripheral part of the subject, such as “cranial front” in b and “lumbar lateral side” in c in FIG. Thus, the influence of the reduction in the compression rate Rc is exerted on the entire image, and the compression rate Rc of the entire image is lowered.
- the radiographic image capturing apparatus 1 is irradiated with radiation so as to eliminate the aperture or reduce the number of omissions and perform imaging.
- a marker such as “R” or “L” is placed on the blank portion in order to prevent the subject photographed in the image from being confused as to the right hand or left hand of the patient. May be photographed in the image together with the subject.
- the missing part must be photographed in the image, but each image data D in the signal line direction according to the present invention and its difference
- image processing on the data ⁇ D it is possible to compress the image data D and the difference data ⁇ D with a high compression rate Rc even when an unclear portion is captured in the image as described above.
- the aperture is narrowed. It is possible and appropriate.
- the image data D output from the plurality of radiation detection elements 7 connected to the line 6 and the difference data ⁇ D thereof are subjected to compression processing, and the compression processing is performed for each signal line 6.
- each image data D read by the same readout circuit 17 and the difference data ⁇ D thereof are compressed, so that each image data D arranged in the conventional scanning line direction It is possible to prevent the compression ratio Rc from being lowered due to the distribution of the image data D and the difference data ⁇ D depending on the variation in the output characteristics of each readout circuit 17 as in the compression process for the difference data ⁇ D. It becomes possible, and it becomes possible to improve the compression rate Rc when compressing the image data D acquired by radiographic imaging and the difference data ⁇ D thereof.
- each image data D read by the same readout circuit 17 and the difference data ⁇ D thereof are distributed in a normal distribution form, they are compressed even if the radiation dose to the radiographic imaging device 1 increases.
- the image data D and the difference data ⁇ D that is, the Huffman code Hc in the present embodiment
- a state in which a short code is assigned to data having a high appearance frequency F is maintained.
- a high compression rate Rc can be maintained regardless of the dose of irradiated radiation. Therefore, it is possible to compress the image data D and the difference data ⁇ D at a high compression rate Rc even in a shooting environment in which a blank portion is captured in an image.
- the image data D and the difference data ⁇ D can be compressed at a high compression rate Rc as in the present embodiment, the amount of data to be transferred is reduced and the transfer time is shortened. It can be reduced.
- the radiographic imaging apparatus 1 is a battery built-in type as shown in the present embodiment, since the power consumption of the battery 41 is reduced, the radiographic imaging apparatus 1 is used for a longer time with one charge. Thus, the use efficiency of the radiation image capturing apparatus 1 can be improved.
- each signal line 6 may be configured to include a Huffman code Hc table.
- the detection unit P can be divided into a plurality of regions extending in the signal line direction, and a Huffman code Hc table can be provided for each division of the regions.
- a table of a plurality of types of Huffman codes Hc is stored in advance in the ROM or the like of the radiation image capturing apparatus 1 for each type or imaging condition, and the control constituting the compression unit.
- the means 22 compresses the image data D and the difference data ⁇ D by performing Huffman coding with reference to the table during the compression process.
- a table of Huffman codes Hc is created based on the obtained image data D and difference data ⁇ D, and image data D and differences are created by referring to the created table. It is also possible to perform a data compression process by performing Huffman coding of the data ⁇ D.
- control means 22 uses, for example, the method shown in FIGS. 12 to 14, and the image data D (n, 1) of the radiation detection elements 7 adjacent to the signal line direction connected to the same signal line 6; Difference data ⁇ D (n + 1,1), ⁇ D (n + 1,2),... Between D (n, 2),... And image data D (n + 1,1), D (n + 1,2),. At this time, each difference data ⁇ D is temporarily stored in the buffer memory 44c (see FIG. 12) without being compressed.
- the control unit 22 Based on the distribution of the difference data ⁇ D, the control unit 22 assigns a Huffman code Hc to each value of the difference data ⁇ D so that data with a higher appearance frequency F is assigned a shorter Huffman code Hc. Create a table. Then, each differential data ⁇ D is read from the buffer memory 44c, a Huffman code Hc corresponding to each differential data ⁇ D is assigned, and each Huffman code Hc which is the compressed differential data ⁇ D is stored again in the buffer memory 44c and accumulated.
- a plurality of buffer memories 44c for example, one for difference data ⁇ D and one for Huffman code Hc may be provided.
- the Huffman code Hc table is created based on the obtained image data D and difference data ⁇ D, and the image is referred to.
- Data compression processing can be performed by performing Huffman coding of data D and difference data ⁇ D.
- a table of Huffman codes Hc is created for each signal line 6, or the detection unit P is divided into a plurality of areas extending in the signal line direction and the Huffman codes are divided for each of the areas. It is also possible to configure to create an Hc table.
- the Huffman code Hc that is, the compressed image data D or the difference data ⁇ D
- the information of the Huffman code Hc table created by the radiation image capturing apparatus 1 is also included. Transfer to an external device is required. Therefore, in this case, the information in the generated Huffman code Hc table is reversibly compressed and transmitted to the external device together with the Huffman code Hc.
- FIG. 18 is a diagram showing an overall configuration of the radiographic image capturing system according to the present embodiment.
- the radiographic imaging system 50 of the present embodiment is a system that assumes radiographic imaging performed in, for example, a hospital or a clinic, and can be employed as a system that captures medical diagnostic images as radiographic images. It is not necessarily limited to this.
- the radiographic image capturing system 50 includes, for example, an imaging room R ⁇ b> 1 that irradiates radiation and images a subject (part of a patient to be imaged) that is a part of a patient, and an operator such as a radiographer.
- an imaging room R ⁇ b> 1 that irradiates radiation and images a subject (part of a patient to be imaged) that is a part of a patient, and an operator such as a radiographer.
- the radiographing room R1 includes a bucky device 51 that can be loaded with the above-described radiographic imaging device 1, a radiation generating device 52 that includes an X-ray tube (not shown) that generates radiation to be irradiated on the subject, and a radiographic image.
- a base station 54 provided with a wireless antenna 53 that relays the communication when the photographing apparatus 1 and the console 58 perform wireless communication is provided.
- the radiographic imaging device 1 is used by being loaded into the cassette holding portion 51a of the bucky device 51.
- the radiographic imaging device 1 is used as the bucky device 51. Or may be formed integrally with a support base or the like.
- the radiographic imaging device 1 and the base station 54 can be connected by a cable so that data can be transmitted by wired communication via the cable.
- the anterior room R2 is equipped with a console 56 for controlling radiation irradiation, which includes a switch means 55 for instructing the radiation generating device 52 to start radiation irradiation, and the like, and the radiation imaging apparatus 1.
- a tag reader 57 for detecting a tag to be described later is provided.
- the console 58 that controls the entire radiographic imaging system 50 is provided outside the imaging room R1 and the front room R2.
- the console 58 is provided in the front room R2. It is also possible to do.
- the console 58 is connected to storage means 59 composed of a hard disk or the like.
- the configuration of the radiographic image capturing apparatus 1 is as described above, but in the present embodiment, the radiographic image capturing apparatus 1 further has the following configuration. The following configuration is not essential.
- a tag (not shown) is built in the radiation image capturing apparatus 1.
- a tag called a so-called RFID (Radio Frequency IDentification) tag is used as the tag, and the tag stores a control circuit that controls each part of the tag and unique information of the radiographic imaging apparatus 1.
- the part is built in compactly.
- the unique information includes, for example, a cassette ID, scintillator type information, size information, resolution, and the like as identification information assigned to the radiation image capturing apparatus 1.
- the radiographic image capturing apparatus 1 may be used by being loaded into the bucky device 51 as described above, but it is not loaded into the bucky device 51 and can be used in a so-called state. .
- the radiation image capturing apparatus 1 is disposed on the upper surface side in a single state, for example, on a bed provided in the imaging room R1 or a bucky apparatus 51B for lying position photographing as shown in FIG. (See FIG. 1)
- the patient's hand which is the subject, can be placed on the top, or the patient's waist, legs, etc. lying on the bed can be inserted between the bed and the bed. It has become.
- radiation image capturing is performed by irradiating the radiation image capturing apparatus 1 with radiation from a portable radiation generating device 52B or the like via a subject.
- the console 58 is constituted by a computer or the like in which a CPU, a ROM, a RAM, an input / output interface and the like (not shown) are connected to a bus.
- a predetermined program is stored in the ROM, and the console 58 reads out the necessary program, expands it in the work area of the RAM, executes various processes according to the program, and controls the entire radiographic imaging system 50 as described above. Is supposed to do.
- the console 58 is connected to the above-described console 56, tag reader 57, storage means 59, and the like, and also includes a bucky device 51A for standing position shooting and lying position shooting via the base station 54 and the console 56. 51B etc. are connected.
- the console 58 is provided with a display screen 58a such as a CRT (Cathode Ray Tube) or LCD (Liquid Crystal Display), and other input means such as a keyboard and a mouse are connected thereto.
- CTR Cathode Ray Tube
- LCD Liquid Crystal Display
- the console 58 of the Huffman code Hc that is, the compressed image data D or the difference data ⁇ D
- the console 58 of the Huffman code Hc that is, the compressed image data D or the difference data ⁇ D
- the console 58 of the Huffman code Hc that is, the compressed image data D or the difference data ⁇ D
- the image data D is restored based on them.
- the console 58 is previously provided with a Huffman code Hc table common to the radiation image capturing apparatus 1.
- the table of the Huffman code Hc is stored in advance in the ROM or the storage means 59 in the console 58, and the console 58 reads out the table from them and performs a restoration process.
- the radiation image capturing apparatus 1 compresses each image data D as it is using the Huffman code Hc table without creating the difference data ⁇ D of each image data D
- the radiation image capturing apparatus when the radiation image capturing apparatus 1 compresses each image data D as it is using the Huffman code Hc table without creating the difference data ⁇ D of each image data D, the radiation image capturing apparatus.
- the Huffman code Hc which is the compressed image data D from 1, is transferred.
- the console 58 refers to the table of the read Huffman code Hc, decompresses each Huffman code Hc, and restores the original Huffman code Hc. The image data is restored.
- the console 58 refers to the table of the read Huffman code Hc and based on each Huffman code Hc.
- the original image data D is restored based on the decompressed original difference data ⁇ D.
- the above-described reference data Dc (1), Dc (2), Dc (3), Dc (4),... are stored in advance in the ROM, the storage means 59, etc. on the console 58 side.
- the Huffman code Hc corresponding to each difference data ⁇ D (1,1), ⁇ D (1,2), ⁇ D (1,3), ⁇ D (1,4),.
- the image data D (1,1) and D (1,2) arranged in the scanning line direction read from the radiation detecting elements 7 connected to the line L1 of the scanning line 5 shown in FIG. , D (1,3), D (1,4),...
- the console 58 stores the restored image data D (1,1), D (1,2), D (1,3), D (1,4),.
- the console 58 corresponds to each difference data ⁇ D (2,1), ⁇ D (2,2), ⁇ D (2,3), ⁇ D (2,4),... With reference to the Huffman code Hc table.
- the original Huffman code Hc is decompressed to restore the original difference data ⁇ D (2,1), ⁇ D (2,2), ⁇ D (2,3), ⁇ D (2,4),.
- the console 58 refers to the table of the Huffman code Hc, decompresses the Huffman code Hc corresponding to each difference data ⁇ D (n, m), and obtains the original difference data ⁇ D (n, m).
- D (n ⁇ 1, m) that was restored and calculated earlier
- the radiographic imaging apparatus 1 and the console 58 are provided with a plurality of types of Huffman code Hc tables in common, information on the table numbers used for the console 58 from the radiographic imaging apparatus 1 is provided.
- the console 58 When the console 58 is configured to transfer, the console 58 reads the table specified by the transferred number information or the like from the ROM or the storage means 59 and performs decompression processing and restoration processing using the table. Configured as follows.
- the imaging order information for specifying the imaging region and imaging direction of the patient's body, which is the subject is often created on the console 58 before imaging. Therefore, when imaging is performed based on the imaging order information, the radiographic imaging apparatus 1 side specifies imaging conditions including an imaging region and an imaging direction based on the imaging order information, and a Huffman code corresponding thereto Since the Hc table is selected, the console 58 side does not receive the transfer of the table number information and the like used from the radiographic image capturing apparatus 1, and uses the Huffman code Hc table to be used based on the imaging order information itself. It can also be configured to select.
- the radiographic imaging apparatus 1 when the radiographic imaging apparatus 1 is configured to transmit the table of the Huffman code Hc suitable for the radiographic imaging conditions from the console 58 side which is an external apparatus every radiographic imaging.
- the console 58 side transmits the same Huffman code Hc as that transmitted to the radiographic imaging apparatus 1. It is also possible to perform a decompression process and a restoration process by referring to the table.
- the radiographic imaging apparatus 1 may be configured to create a table of Huffman codes Hc each time image data D and difference data ⁇ D are compressed.
- the console 58 refers to the Huffman code Hc table transferred together with the Huffman code Hc from the radiographic image capturing apparatus 1 and restores the original difference data ⁇ D in the same manner as described above. The image data D is restored.
- the reference data Dc (1), Dc (2), Dc (3), Dc (4),... are also subjected to the compression processing of the image data D and the difference data ⁇ D in the radiographic image capturing apparatus 1.
- the console 58 restores the original difference data ⁇ D in the same manner as described above based on the reference data Dc transferred together with the Huffman code Hc table.
- the image data D is configured to be restored.
- the compressed image data D and the difference data ⁇ D transferred from the radiation image capturing apparatus 1 are converted into the original image data D and the original difference data. It is possible to restore the image data so as to completely match ⁇ D, and it is possible to reliably restore each image data D captured by the radiation image capturing apparatus 1.
- the radiographic imaging apparatus 1 performs compression processing on each image data D and each differential data ⁇ D in the signal line direction.
- ⁇ D can be compressed at a high compression rate Rc, and the data transfer time is shortened and the power consumption is reduced. Therefore, even when viewed as the entire system, it is possible to shorten the data transfer time and reduce power consumption.
- the radiographic image capturing apparatus 1 transfers thinned image data (hereinafter referred to as thinned data) to the console 58, and then automatically transfers the remaining image data D or all image data D to the console 58 side.
- thinned data hereinafter referred to as thinned data
- an operator such as a radiologist looks at the preview thinned image and confirms whether or not the subject is properly photographed in the image photographed by the radiation image photographing apparatus 1 (in the thinned image). It may be configured as follows. In this case, the operator confirms the thinned image, and if the subject is properly captured in the image, the operator transfers the entire image data D and the like from the radiation image capturing apparatus 1 again so that the subject is appropriately captured in the image. If not, the radiographic imaging device 1 is made to discard the image data D and perform another operation such as radiographic imaging.
- Thinning-out data is created in such a manner that image data D arranged in the scanning line direction is extracted every predetermined number of lines from the image data D output from the radiation detection elements 7 connected to the lines L1 to Lx. A case (that is, a case of so-called line thinning) will be described.
- the predetermined number of thinning out the image data D can be set to an appropriate number, and is not limited to the case of every two lines.
- control means 22 of the radiographic image capturing apparatus 1 creates the difference data D for the image data D in the signal line direction by the same processing as the processing shown in FIG. 12 to FIG.
- the means 22 reads only the image data D arranged in the directions of the lines L1, L4, L7,... Of the scanning line 5 from the storage means 40 of the radiographic image capturing apparatus 1.
- control unit 22 firstly sets the image data D (1,1), D (1,2), D (1,3), D (1,4) arranged in the line L1 direction of the scanning line 5 from the storage unit 40. ),... And reference data Dc (1), Dc (2), Dc (3), Dc (4),... And their difference data ⁇ D (1,1), ⁇ D (1, 2), ⁇ D (1, 3), ⁇ D (1, 4),... Are created, and the difference data ⁇ D is compressed with reference to the table of the Huffman code Hc.
- the control means 22 skips the image data D arranged in the direction of the lines L2 and L3 of the scanning line 5, and the image data D (4, 1), D arranged in the direction of the line L4 of the scanning line 5 from the storage means 40.
- (4,2), D (4,3), D (4,4),... Are read and image data D (1,1), D (1,2), D arranged in the line L1 direction of the scanning line 5 are read.
- Difference data ⁇ D (4,1), ⁇ D (4,2), ⁇ D (4,3), ⁇ D (4,4) between (1,3), D (1,4),. ),... Are created, and the difference data ⁇ D is compressed with reference to the table of the Huffman code Hc.
- the console 58 refers to the Huffman code Hc table read from the ROM or the like and refers to each Huffman code. Decompress Hc to restore the original image data.
- the console 58 uses the read Huffman code Hc table in the same manner as described above. Referring to each Huffman code Hc, the original difference data ⁇ D is decompressed, and the decompressed original data is used by using the reference data Dc (1), Dc (2), Dc (3), Dc (4),. The original image data D is restored based on the difference data ⁇ D.
- the console 58 forms a thinned image based on the restored original image data D and displays it on the display screen 58a (see FIG. 18). At this time, all the data of the thinned image may be formed and displayed on the display screen 58a, and the image data D arranged in the direction of the lines L1, L4, L7,. It is also possible to configure the display screen 58a to sequentially display each time.
- the console 58 inputs an instruction from the operator. Wait for.
- the operator confirms the thinned image displayed on the display screen 58a and determines that the subject is not properly captured in the image
- the operator applies the radiographic image capturing apparatus 1 via the console 58 or the like.
- unnecessary image data D obtained by radiographic imaging is discarded and re-imaging is performed again, and it is determined that the subject is appropriately captured in the image
- radiographic imaging is performed via the console 58.
- a request signal is transmitted to the apparatus 1 so as to transfer other image data D obtained by the radiographic imaging.
- the control unit 22 of the radiographic image capturing apparatus 1 receives a transfer request for other image data D from the console 58, the remaining lines L2, L3, L5, L6,. Only the image data D arranged in a row are read out. As described above, when all the image data D (or difference data ⁇ D) is automatically transferred after transferring the thinned data, the above-mentioned is automatically performed without waiting for a transfer request from the console 58. Only the image data D are read out.
- control unit 22 firstly sets the image data D (2,1), D (2,2), D (2,3), D (2,4) arranged in the line L2 direction of the scanning line 5 from the storage unit 40. ),... And reference data Dc (1), Dc (2), Dc (3), Dc (4),... And their difference data ⁇ D (2, 1), ⁇ D (2, 2), ⁇ D (2, 3), ⁇ D (2, 4),... Are created, and the difference data ⁇ D is compressed with reference to the table of the Huffman code Hc.
- control means 22 sends image data D (3, 1), D (3, 2), D (3, 3), D (3,4) from the storage means 40 in the direction of the line L3 of the scanning line 5. ,... And image data D (2,1), D (2,2), D (2,3), D (2,4),. Difference data ⁇ D (3,1), ⁇ D (3,2), ⁇ D (3,3), ⁇ D (3,4),... Are created and the difference between them is referred to the Huffman code Hc table. The data ⁇ D is compressed.
- the console 58 refers to the Huffman code Hc table read from the ROM or the like and refers to each Huffman code. Decompress Hc to restore the original remaining image data.
- the console 58 uses the read Huffman code Hc table in the same manner as described above. Referring to each Huffman code Hc, the original difference data ⁇ D is decompressed, and the decompressed original data is used by using the reference data Dc (1), Dc (2), Dc (3), Dc (4),. The original remaining image data D is restored based on the difference data ⁇ D.
- the console 58 combines the restored original remaining image data D and the image data D previously transferred and restored as a thinned image, and synthesizes the combined original image data shown in FIG. Data D is restored. Based on this, a complete radiographic image that is not a thinned image is formed.
- the console 58 saves the restored original whole image data D in the storage unit 59, and performs the above-described gain correction on the restored original whole image data D in accordance with an instruction from the operator or automatically.
- the image correction process is performed or displayed on the display screen 58a.
- the original entire image data D may be restored and displayed on the display screen 58a, and the image data D arranged in the directions of the scanning lines 5 in the lines L1 to Lx may be restored. It is also possible to configure the display screen 58a to sequentially display each time it is performed.
- the image data D arranged in the direction of the remaining lines L2, L3, L5, L6,... Of the scanning line 5 is converted into the lines L1, L4, L7,. ... It is also possible to perform a Huffman coding depending on the image data D arranged in the direction and restore it.
- the reference data Dc (1), Dc (2), Dc (3), Dc (4) instead of creating the difference data ⁇ D from the image data D, as shown in FIG. 21, the respective image data D (1,1), D (1,2), D arranged in the direction of the line L1 of the scanning line 5 (1,3), D (1,4),..., And the image data D (2,1), D (2,2), D (2,3), D arranged in the direction of the line L2 of the scanning line 5.
- the difference data ⁇ D is compressed by referring to them.
- each image data D arranged in the direction of the line L3 of the scanning line 5
- each image data D (2, 1), D (2, 2), D (2, 3) arranged in the direction of the line L2 of the scanning line 5 is used.
- D (2, 4) ..., D (3, 1), ⁇ D (3, 2), ⁇ D (3, 3), ⁇ D (3, 4),.
- the difference data ⁇ D is compressed with reference to the table.
- the console 58 refers to the table of the Huffman code Hc and decompresses each Huffman code Hc, which is the compressed difference data ⁇ D, into the original difference data ⁇ D. Then, the image data D arranged in the direction of the lines L1, L4, L7, L10,... Of the scanning line 5 already restored as the thinned data, and the difference data ⁇ D (2, 1),. (5,1),..., .DELTA.D (8,1),..., .DELTA.D (11,1),..., Are added to each other, and are arranged in the lines L2, L5, L8, L11,. Each image data D is restored.
- the original image data D arranged in the direction of the lines L2, L5, L8, L11,... Of the restored scanning line 5 and the difference data ⁇ D (3, 1),. ,..., .DELTA.D (9,1),..., .DELTA.D (12,1),... are added, and the original image data arranged in the direction of the lines L3, L6, L9, L12,. Restore D.
- the thinned data is generated so that the data amount is reduced to 1/9 or 1/16 of the total image data D.
- the control means 22 reads the image data D (1,1), D (1,4),... From the storage means 40, and the reference data Dc (1), Dc (4),. Difference data ⁇ D (1,1), ⁇ D (1,4),... Are created, and then image data D (4,1), D (4,4),. The process of creating the difference data ⁇ D (4,1), ⁇ D (4,4),... With the data D (1,1), D (1,4),. . Then, the difference data ⁇ D is compressed with reference to the Huffman code Hc table and transferred to the console 58 as described above.
- the console 58 decompresses the Huffman code Hc, which is the compressed difference data ⁇ D transferred from the radiation image capturing apparatus 1, to the original difference data ⁇ D with reference to the Huffman code Hc table.
- the original image data D is restored based on the decompressed original difference data ⁇ D by using the reference data Dc (1), Dc (4),.
- the control unit 22 of the radiographic image capturing apparatus 1 receives the transfer request for other image data D from the console 58 or automatically transfers the thinned data, and then the same method as described above for the remaining image data D. Then, the difference data ⁇ D is created, compressed and transferred.
- each difference data ⁇ D is created (that is, by the method shown in FIG. 20 or FIG. 21), and the other image data D (1,2), D (1,3), D (1,5), D For the image data D arranged downward from (1, 6),..., Each difference data ⁇ D is created in the manner of creating the difference data ⁇ D with respect to the normal image data D (see FIGS. 11 to 14). Compress.
- the console 58 for the image data D arranged below the image data D (1,1), D (1,4),... In FIG.
- the Huffman code Hc which is ⁇ D, is decompressed to the original difference data ⁇ D, and the original image data D is restored based on them.
- image data D arranged below from image data D (1,2), D (1,3), D (1,5), D (1,6) for image data D arranged below from image data D (1,2), D (1,3), D (1,5), D (1,6),.
- the Huffman code Hc which is the compressed difference data ⁇ D, is decompressed into the original difference data ⁇ D by decompressing and restoring the difference data ⁇ D with respect to D, and the original image data D is restored based on them.
- the restored original remaining image data D and the image data D previously transferred and restored as a thinned image are combined and combined to completely restore the original whole image data D shown in FIG. .
- the image data D (1, 1), D (1, 4),... are arranged downward (that is, arranged in the signal line direction) and the image data D (1, 2). ), D (1,3), D (1,5), D (1,6),...,
- the processing for the image data D arranged downward is different, so that the difference data ⁇ D is created or compressed.
- the configuration of the decompression process and the restoration process on the console 58 side may be complicated.
- the method of creating and compressing all the image data D and the difference data ⁇ D transferred after transferring the thinned image is appropriately determined in consideration of the interface between the radiographic image capturing apparatus 1 and the console 58 and the like.
- the thinned data when transferring the thinned data, the thinned data is not compressed, or the difference data ⁇ D is not created and compressed.
- the raw thinned data that is not compressed is transferred to the console 58 side as it is. It may not take. That is, there is a case where there is not much difference in the time until the transfer is completed between the case where the difference data ⁇ D is created from the thinned data and compressed and transferred, and the case where the raw thinned data which is not compressed is transferred as it is. .
- the radiographic image capturing apparatus 1 and the radiographic image capturing system 50 according to the present embodiment even when the compressed image data is compressed and transferred, the normal image data shown in the above embodiment is used.
- the compression process for D and difference data ⁇ D it is possible to compress the data of the thinned image at a high compression rate Rc. For this reason, the data transfer time is shortened and the power consumption can be reduced.
- the table of the Huffman code Hc is stored in the control means 22 of the radiation image capturing apparatus 1, the ROM of the console 58, etc.
- the table is used by selecting from a plurality of types of tables or created on the radiation image capturing apparatus 1 side. It goes without saying that the table can be transferred to the console 58 side, or the table can be transmitted from the console 58 to the radiographic imaging apparatus 1 every radiographic imaging.
Abstract
Description
互いに交差するように配設された複数の走査線および複数の信号線と、前記複数の走査線および複数の信号線により区画された各領域に二次元状に配列された複数の放射線検出素子とを備える検出部と、
前記放射線検出素子から前記信号線を通じて電荷を読み出し、前記放射線検出素子ごとに前記電荷を電気信号に変換して画像データとして出力する読み出し回路と、
前記放射線検出素子ごとの画像データに関して圧縮処理を行う圧縮手段と、
を備え、
前記圧縮手段は、前記信号線ごとに、同じ前記信号線に接続された複数の前記放射線検出素子から出力された前記各画像データに対する圧縮処理を行うことを特徴とする。
互いに交差するように配設された複数の走査線および複数の信号線と、前記複数の走査線および複数の信号線により区画された各領域に二次元状に配列された複数の放射線検出素子とを備える検出部と、
前記放射線検出素子から前記信号線を通じて電荷を読み出し、前記放射線検出素子ごとに前記電荷を電気信号に変換して画像データとして出力する読み出し回路と、
前記放射線検出素子ごとの画像データに関して圧縮処理を行う圧縮手段と、
を備え、
前記圧縮手段は、同じ前記信号線に接続された複数の前記放射線検出素子から出力された前記各画像データについて、隣接する前記放射線検出素子の前記画像データ同士の差分を算出して差分データを作成し、当該差分データに対して圧縮処理を行うことを特徴とする。
互いに交差するように配設された複数の走査線および複数の信号線と、前記複数の走査線および複数の信号線により区画された各領域に二次元状に配列された複数の放射線検出素子とを備える検出部と、
前記放射線検出素子から前記信号線を通じて電荷を読み出し、前記放射線検出素子ごとに前記電荷を電気信号に変換して画像データとして出力する読み出し回路と、
前記画像データから走査線単位毎の画像データを間引き抽出して間引きデータを生成する間引きデータ生成手段と、
前記間引きデータに対して圧縮処理を行う圧縮手段と、
を備え、
前記圧縮手段は、信号線方向に隣接する前記間引きデータに対して圧縮処理を行う又は、信号線方向に隣接する前記間引きデータに対して差分を算出して差分データを作成し当該差分データに対して圧縮処理を行うことを特徴とする。
前記圧縮処理が施された前記画像データを転送する転送手段を備える放射線画像撮影装置と、
前記放射線画像撮影装置から転送されてきた前記圧縮処理が施された前記画像データを元の前記画像データに解凍して復元するコンソールと、
を備えることを特徴とする。
前記圧縮処理が施された前記差分データを転送する転送手段を備える放射線画像撮影装置と、
前記放射線画像撮影装置から転送されてきた前記圧縮処理が施された前記差分データを元の前記差分データに解凍し、解凍した前記元の差分データに基づいて元の前記画像データを復元するコンソールと、
を備えることを特徴とする。
[放射線画像撮影装置]
図1は、本実施形態に係る放射線画像撮影装置の外観斜視図であり、図2は、図1のA-A線に沿う断面図である。本実施形態に係る放射線画像撮影装置1は、図1や図2に示すように、筐体2内にシンチレータ3や基板4等が収納されて構成されている。
[放射線画像撮影システム]
ここで、本実施形態に係る放射線画像撮影装置1から圧縮された画像データDや差分データΔD(すなわちハフマンコードHc)の転送を受けた外部装置側での画像データDの復元について説明する。以下、まず、放射線画像撮影システムの構成について説明する。
Dc(m)+ΔD(1,m)→D(1,m) …(1)
を演算して、走査線方向に並ぶ元の画像データD(1,1)、D(1,2)、D(1,3)、D(1,4)、…を復元する。この処理は、図13に示した走査線5のラインL1に接続された各放射線検出素子7から読み出された走査線方向に並ぶ各画像データD(1,1)、D(1,2)、D(1,3)、D(1,4)、…に対する処理の逆の処理に相当する。
D(1,m)+ΔD(2,m)→D(2,m) …(2)
を演算して、走査線方向に並ぶ元の画像データD(2,1)、D(2,2)、D(2,3)、D(2,4)、…を復元し、復元した画像データD(2,1)、D(2,2)、D(2,3)、D(2,4)、…を記憶手段59に保存する。
D(n-1,m)+ΔD(n,m)→D(n,m) …(3)
を演算していくことで、全ての画像データD(n,m)を順次復元するようになっている。
[間引き画像を転送する場合]
放射線画像撮影システム50のコンソール58の表示画面58aに、放射線画像撮影装置1で撮影した放射線画像の全画像データDを表示するのに先立って、画像データDから所定の割合で画素を間引いた、いわゆる間引き画像をプレビュー用に表示するように構成される場合もある。
5、L1~Lx、Ln 走査線
6 信号線
7、(n,m) 放射線検出素子
8 TFT(スイッチ手段)
17 読み出し回路
22 制御手段(圧縮手段、間引きデータ生成手段)
39 アンテナ装置(転送手段)
40 記憶手段
44 レジスタ部(圧縮手段、間引きデータ生成手段)
44a、44b バッファレジスタ
50 放射線画像撮影システム
58 コンソール
D、D(n,m) 画像データ
Dc(1)、Dc(2) 基準データ
Hc ハフマンコード
P 検出部
r 領域
ΔD、ΔD(n,m) 差分、差分データ
Claims (16)
- 互いに交差するように配設された複数の走査線および複数の信号線と、前記複数の走査線および複数の信号線により区画された各領域に二次元状に配列された複数の放射線検出素子とを備える検出部と、
前記放射線検出素子から前記信号線を通じて電荷を読み出し、前記放射線検出素子ごとに前記電荷を電気信号に変換して画像データとして出力する読み出し回路と、
前記放射線検出素子ごとの画像データに関して圧縮処理を行う圧縮手段と、
を備え、
前記圧縮手段は、前記信号線ごとに、同じ前記信号線に接続された複数の前記放射線検出素子から出力された前記各画像データに対する圧縮処理を行うことを特徴とする放射線画像撮影装置。 - 互いに交差するように配設された複数の走査線および複数の信号線と、前記複数の走査線および複数の信号線により区画された各領域に二次元状に配列された複数の放射線検出素子とを備える検出部と、
前記放射線検出素子から前記信号線を通じて電荷を読み出し、前記放射線検出素子ごとに前記電荷を電気信号に変換して画像データとして出力する読み出し回路と、
前記放射線検出素子ごとの画像データに関して圧縮処理を行う圧縮手段と、
を備え、
前記圧縮手段は、同じ前記信号線に接続された複数の前記放射線検出素子から出力された前記各画像データについて、隣接する前記放射線検出素子の前記画像データ同士の差分を算出して差分データを作成し、当該差分データに対して圧縮処理を行うことを特徴とする放射線画像撮影装置。 - 前記走査線を介してスイッチ手段がオン状態とされて前記各放射線検出素子から出力された走査線方向に並ぶ前記各画像データ、または記憶手段から読み出された前記走査線方向に並ぶ前記各画像データを一時的に蓄積する少なくとも2つのバッファレジスタを備え、
前記圧縮手段は、隣接する前記走査線の前記走査線方向に並ぶ前記各画像データを前記2つのバッファレジスタに一時的に蓄積させ、前記2つのバッファレジスタの同じ番地の前記画像データ同士の差分を算出することで、同じ前記信号線に接続された隣接する前記放射線検出素子の前記画像データ同士の前記差分データを作成することを特徴とする請求項2に記載の放射線画像撮影装置。 - 前記圧縮手段は、前記隣接する走査線の前記走査線方向に並ぶ前記各画像データ同士の差分を算出すると、一方の前記走査線の前記走査線方向に並ぶ前記各画像データを現在蓄積されている前記バッファレジスタから他方の前記バッファレジスタに移し、空になった前記バッファレジスタに前記一方の走査線に隣接する前記走査線の前記走査線方向に並ぶ前記各画像データを蓄積させて、前記2つのバッファレジスタの同じ番地の前記画像データ同士の差分を算出する処理を繰り返すことで前記差分データを作成することを特徴とする請求項3に記載の放射線画像撮影装置。
- 前記走査線を介してスイッチ手段がオン状態とされて前記各放射線検出素子から出力された走査線方向に並ぶ前記各画像データ、または記憶手段から読み出された前記走査線方向に並ぶ前記各画像データを一時的に蓄積する少なくとも1つのバッファレジスタを備え、
前記圧縮手段は、隣接する前記走査線の前記走査線方向に並ぶ前記各画像データのうち、一方の前記走査線の前記走査線方向に並ぶ前記各画像データを前記1つのバッファレジスタに一時的に蓄積させ、他方の前記走査線の前記走査線方向に並ぶ前記各画像データをそれぞれ対応する前記一方の走査線の前記各画像データと置換して蓄積する際に、前記画像データ同士の差分を算出することで、同じ前記信号線に接続された隣接する前記放射線検出素子の前記画像データ同士の前記差分データを作成することを特徴とする請求項2に記載の放射線画像撮影装置。 - 前記圧縮手段が最初の前記走査線の前記走査線方向に並ぶ前記各画像データの差分を算出する際の基準となる基準データを備えることを特徴とする請求項3から請求項5のいずれか一項に記載の放射線画像撮影装置。
- 前記圧縮処理のためのハフマンコードのテーブルを予め備え、
前記圧縮手段は、前記テーブルを参照して前記画像データまたは前記差分データのハフマン符号化を行って前記放射線検出素子ごとの前記画像データまたは前記差分データに関して圧縮処理を行うことを特徴とする請求項1から請求項6のいずれか一項に記載の放射線画像撮影装置。 - 被写体である患者の身体の撮影部位を含む撮影条件ごとに前記圧縮処理のためのハフマンコードのテーブルを予め備え、
前記圧縮手段は、設定された前記撮影条件に応じて前記テーブルを選択し、選択した前記テーブルを参照して前記画像データまたは前記差分データのハフマン符号化を行って前記放射線検出素子ごとの前記画像データまたは前記差分データに関して圧縮処理を行うことを特徴とする請求項1から請求項6のいずれか一項に記載の放射線画像撮影装置。 - 前記圧縮手段は、前記画像データまたは前記差分データの圧縮処理時に、前記画像データまたは前記差分データに基づいて前記圧縮処理のためのハフマンコードのテーブルを作成し、前記テーブルを参照して前記画像データまたは前記差分データのハフマン符号化を行って前記放射線検出素子ごとの画像データに関して圧縮処理を行うことを特徴とする請求項1から請求項6のいずれか一項に記載の放射線画像撮影装置。
- 前記圧縮手段は、放射線画像撮影ごとに送信されてくる前記圧縮処理のためのハフマンコードのテーブルを参照して前記画像データまたは前記差分データのハフマン符号化を行って前記放射線検出素子ごとの前記画像データまたは前記差分データに関して圧縮処理を行うことを特徴とする請求項1から請求項6のいずれか一項に記載の放射線画像撮影装置。
- 互いに交差するように配設された複数の走査線および複数の信号線と、前記複数の走査線および複数の信号線により区画された各領域に二次元状に配列された複数の放射線検出素子とを備える検出部と、
前記放射線検出素子から前記信号線を通じて電荷を読み出し、前記放射線検出素子ごとに前記電荷を電気信号に変換して画像データとして出力する読み出し回路と、
前記画像データから走査線単位毎の画像データを間引き抽出して間引きデータを生成する間引きデータ生成手段と、
前記間引きデータに対して圧縮処理を行う圧縮手段と、
を備え、
前記圧縮手段は、信号線方向に隣接する前記間引きデータに対して圧縮処理を行う又は、信号線方向に隣接する前記間引きデータに対して差分を算出して差分データを作成し当該差分データに対して圧縮処理を行うことを特徴とする放射線画像撮影装置。 - 前記間引きデータ生成手段は、信号線単位毎の画像データを間引き抽出することを特徴とする請求項11に記載の放射線画像撮影装置。
- 前記圧縮処理が施された前記画像データを転送する転送手段を備える請求項1に記載の放射線画像撮影装置と、
前記放射線画像撮影装置から転送されてきた前記圧縮処理が施された前記画像データを元の前記画像データに解凍して復元するコンソールと、
を備えることを特徴とする放射線画像撮影システム。 - 前記圧縮処理が施された前記差分データを転送する転送手段を備える請求項2から請求項6のいずれか一項に記載の放射線画像撮影装置と、
前記放射線画像撮影装置から転送されてきた前記圧縮処理が施された前記差分データを元の前記差分データに解凍し、解凍した前記元の差分データに基づいて元の前記画像データを復元するコンソールと、
を備えることを特徴とする放射線画像撮影システム。 - 前記圧縮処理が施された前記画像データまたは前記差分データを転送する転送手段を備える請求項10に記載の放射線画像撮影装置と、
放射線画像撮影ごとに前記圧縮処理のためのハフマンコードのテーブルを送信するコンソールと、
を備え、
前記コンソールは、前記放射線画像撮影装置に送信した前記テーブルを参照して前記放射線画像撮影装置から転送されてきた前記圧縮処理が施された前記差分データを元の前記差分データに解凍し、解凍した前記元の差分データに基づいて元の前記画像データを復元することを特徴とする放射線画像撮影システム。 - 前記圧縮処理が施された前記所定の画像データまたは前記圧縮処理が施された前記差分データを転送する転送手段を備える請求項11又は12に記載の放射線画像撮影装置と、
前記放射線画像撮影装置から転送されてきた前記圧縮処理が施された前記間引きデータまたは前記圧縮処理が施された前記差分データに基づいて元の前記所定の画像データを復元して間引き画像を形成するコンソールと、
を備えることを特徴とする放射線画像撮影システム。
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06133171A (ja) * | 1992-10-15 | 1994-05-13 | Fuji Photo Film Co Ltd | 画像データ圧縮方法および装置 |
JP2002064750A (ja) * | 2000-08-21 | 2002-02-28 | Japan Science & Technology Corp | 高速撮像装置 |
JP2003234967A (ja) * | 2002-02-12 | 2003-08-22 | Photron Ltd | 高速撮像装置 |
JP2005217896A (ja) * | 2004-01-30 | 2005-08-11 | Shoji Kawahito | 画像符号化装置 |
JP2006263322A (ja) * | 2005-03-25 | 2006-10-05 | Konica Minolta Medical & Graphic Inc | 放射線画像撮影システム、コンソール、コンソールで実行されるプログラム |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
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US5272535A (en) * | 1991-06-13 | 1993-12-21 | Loral Fairchild Corporation | Image sensor with exposure control, selectable interlaced, pseudo interlaced or non-interlaced readout and video compression |
US5661309A (en) | 1992-12-23 | 1997-08-26 | Sterling Diagnostic Imaging, Inc. | Electronic cassette for recording X-ray images |
JP3486490B2 (ja) | 1995-09-04 | 2004-01-13 | キヤノン株式会社 | 放射線検出装置 |
JP2000275350A (ja) | 1999-03-26 | 2000-10-06 | Fuji Photo Film Co Ltd | 放射線固体検出カセッテ |
JP2005287927A (ja) | 2004-04-02 | 2005-10-20 | Konica Minolta Medical & Graphic Inc | 画像処理装置、画像処理方法及び医用画像システム |
JP4012182B2 (ja) | 2004-08-19 | 2007-11-21 | キヤノン株式会社 | カセッテ型x線画像撮影装置 |
EP2176685A2 (en) * | 2007-08-08 | 2010-04-21 | Koninklijke Philips Electronics N.V. | Silicon photomultiplier readout circuitry |
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Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06133171A (ja) * | 1992-10-15 | 1994-05-13 | Fuji Photo Film Co Ltd | 画像データ圧縮方法および装置 |
JP2002064750A (ja) * | 2000-08-21 | 2002-02-28 | Japan Science & Technology Corp | 高速撮像装置 |
JP2003234967A (ja) * | 2002-02-12 | 2003-08-22 | Photron Ltd | 高速撮像装置 |
JP2005217896A (ja) * | 2004-01-30 | 2005-08-11 | Shoji Kawahito | 画像符号化装置 |
JP2006263322A (ja) * | 2005-03-25 | 2006-10-05 | Konica Minolta Medical & Graphic Inc | 放射線画像撮影システム、コンソール、コンソールで実行されるプログラム |
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