Abstract:
Provided is an apparatus for acquiring a digital X-ray image that radiates X-ray on a patient&#39;s part by using a high sensitivity imaging plate (IP), reads the radiated patient&#39;s part, acquires a signal including patient information and image information regarding a patient, converts the signal into a digital signal, and links the digital signal to external equipment.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATION 
     This application claims the benefit of Korean Patent Application No. 10-2009-0028265, filed on Apr. 1, 2009, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an apparatus for acquiring a digital X-ray image, and more particularly to, an apparatus for acquiring a digital X-ray image that radiates X-ray on a patient&#39;s part by using a high sensitivity imaging plate (IP), reads the radiated patient&#39;s part, acquires a signal including patient information and image information regarding a patient, converts the signal into a digital signal, and links the digital signal to external equipment. 
     2. Description of the Related Art 
     Computed radiography (CR) conventionally scans X-ray of X-ray equipments on an imaging plate (IP) in stead of a film, inserts the IP into CR equipment, scans a laser beam, and acquires an image signal from latent images accumulated in the IP. 
     Conventional X-ray images are acquired by scanning X-ray to a film and developing the film. Such conventional methods of acquiring X-ray images additionally need films, developing solutions, developers, places for storing a large amount of films, etc. and require re-capturing of X-ray images when the X-ray images are improperly captured. 
     Further, since a pickup image is viewed by capturing the pickup image in a film and developing the film, a doctor cannot immediately view an X-ray result and must undergo an additional developing process to view an X-ray image. 
     Meanwhile, Korean Laid-Open Patent No. 2008-0026338 discloses an optical source of optical coherence tomography, and U.S. Pat. No. 7,397,059 discloses a radiation image reading system as the conventional arts. 
     SUMMARY OF THE INVENTION 
     The present invention provides an apparatus for acquiring a digital X-ray image that radiates X-ray on a patient&#39;s part by using a high sensitivity imaging plate (IP), reads the radiated patient&#39;s part, acquires a signal including patient information and image information regarding a patient, converts the signal into a digital signal, and links the digital signal to external equipment. 
     The present invention also provides an apparatus for acquiring a digital X-ray image that makes it possible to always view an image in an optimal state by adjusting brightness and luminance of the image in various ways using provided software. 
     The present invention also provides an apparatus for acquiring a digital X-ray image that is easy for carrying in a cassette way. 
     The present invention also provides an apparatus for acquiring a digital X-ray image that can secure sufficient time to make laser staying on an IP. 
     According to an aspect of the present invention, there is provided an apparatus for acquiring a digital X-ray image that inserts an imaging plate (IP) into the entrance of a case body, scans a laser beam onto the IP, and acquires an image signal from latent images accumulated by scanning radiation onto the IP  2 , the apparatus including: a laser beam scanning unit guiding the laser beam generated from laser; a reflection mirror installed in the entrance of the case body and having the laser beam scanned by the laser beam scanning unit reflected onto the IP without emitting the laser beam to the outside; a dichroic filter transmitting through the laser beam reflected by the reflection mirror to be scanned on the IP and reflecting a blue wavelength light having photostimulated luminescence on the IP by the scanning of the laser beam; an optical fiber transferring the blue wavelength light having photostimulated luminescence on the IP to a band-pass filter; a band-pass filter transmitting the blue wavelength light therethrough and preventing a red wavelength light from transmitting therethrough in order to acquire the blue wavelength light transferred through the optical fiber; a photo-multiplication tube acquiring and collecting blue wavelength image signals transmitting through the band-pass filter and amplifying images; two position detection sensors installed at both ends of the entrance of the case body and detecting positions where the laser beam is scanned; a transfer member installed inside the case body, having the IP hooked thereto, and transferring the IP forward and backward; a power transmission unit transmitting power to allow the transfer member to operate; and a controller controlling the operations of the laser, the laser beam scanning unit, the position detection sensors, and the power transmission unit. 
     The laser beam scanning unit may include: a swing mirror swing left and right according to power applied from the outside and scanning the laser beam generated from the laser; a F-theta lens adjusting a focal distance of the laser beam deflected in the swing mirror; and an auxiliary mirror reflecting the laser beam which has passed through the F-theta lens to a scanning region. 
     The swing mirror may include: a flow plate having a mirror fixed to the front surface of the flow plate; two magnets installed at both sides of the rear surface of the flow plate; a fixing plate installed to face the flow plate by a predetermined space and having two coils installed in the positions corresponding to the magnets; and two springs each connected to two connection rods that protrude from both sides of the flow plate and the fixing plate. 
     The dichroic filter may be installed to have an inclination angle of 45 degrees with respect to light that is input into the optical fiber. 
     The transfer member may include: a rail installed on the bottom of the inner portion of the case body in a horizontal direction; a transfer rod movably installed in the rail and having both ends fixed to a belt of the power transmission unit; and two hooks installed in one side of the transfer rod to have the IP hooked thereto. 
     The power transmission unit may include: a driving pulley fixed to the driving axis of a motor; a following pulley connected to the driving pulley via a first belt and rotating and connected to two roller shafts; the roller shafts installed in both sides of the inner portion of the case body and connected to the following pulley and first and second pulleys; and two second belts wound around the first and second pulleys of the roller shaft and transferring a rotational force. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which: 
         FIG. 1  is a schematic perspective view of an apparatus for acquiring a digital X-ray image according to an embodiment of the present invention; 
         FIG. 2  is a block view of the apparatus for acquiring the digital X-ray image according to an embodiment of the present invention; 
         FIG. 3  is a perspective view of a transfer member and a power transmission unit of the apparatus for acquiring the digital X-ray image according to an embodiment of the present invention; 
         FIG. 4  is a perspective view of a swing mirror of the apparatus for acquiring the digital X-ray image according to an embodiment of the present invention; 
         FIGS. 5A and 5B  are plan views of the swing mirror shown in  FIG. 4  in an operation state according to an embodiment of the present invention; 
         FIG. 6  is a view of a main part of the apparatus for acquiring the digital X-ray image according to an embodiment of the present invention; 
         FIG. 7  is a timing diagram of an output signal of two position detection sensors according to an embodiment of the present invention; and 
         FIG. 8  is a schematic perspective view of an apparatus for acquiring a digital X-ray image according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Hereinafter, the present invention will be described in detail by explaining embodiments of the invention with reference to the attached drawings. 
       FIG. 1  is a schematic perspective view of an apparatus for acquiring a digital X-ray image according to an embodiment of the present invention.  FIG. 2  is a block view of the apparatus for acquiring the digital X-ray image according to an embodiment of the present invention.  FIG. 3  is a perspective view of a transfer member  5  and a power transmission unit  6  of the apparatus for acquiring the digital X-ray image according to an embodiment of the present invention.  FIG. 4  is a perspective view of a swing mirror  41  of the apparatus for acquiring the digital X-ray image according to an embodiment of the present invention.  FIGS. 5A and 5B  are plan views of the swing mirror  41  shown in  FIG. 4  in an operation state according to an embodiment of the present invention.  FIG. 6  is a view of a main part of the apparatus for acquiring the digital X-ray image according to an embodiment of the present invention.  FIG. 7  is a timing diagram of an output signal of two position detection sensors  16  according to an embodiment of the present invention. 
     Referring to  FIGS. 1 through 3 , the apparatus for acquiring the digital X-ray image of the present embodiment, which inserts an imaging plate (IP)  2  into an entrance of a case body  1 , scans a laser beam on the IP  2 , and acquires an image signal from latent images accumulated by scanning radiation to the IP  2 , includes a laser beam scanning unit  4 , a reflection mirror  11 , a dichroic filter  12 , an optical fiber  13 , a band pass filter  14 , a photo-multiplication tube  15 , the position detection sensors  16 , the transfer member  5 , the power transmission unit  6 , and a controller  7 . 
     The apparatus for acquiring the digital X-ray image of the present embodiment is in a cassette way, and is easy for carrying, and thus it is convenient to install the apparatus at any places. 
     With regard to the characteristics of the IP  2 , if the IP  2  is X-ray radiated, a latent image having energy which is in proportion to an X-ray scanning amount exists on the IP  2 . If the IP  2  is scanned with a red wavelength laser, the latent image generated by the X-ray radiation is expressed in a blue wavelength. After an image is acquired by scanning the IP  2  with the red laser, the latent image remaining after the IP 2  is scanned is removed in order to reuse the IP  2 . Therefore, if the IP  2  is exposed to a strong light, the remaining latent image is removed. 
     The elements of the apparatus for acquiring the digital X-ray image of the present embodiment are mounted inside the case body  1  in which a cover  17  can be opened and closed and is installed in the upper portion of the case body  1 , the transfer member  5  for transferring the IP  2  is installed, and the power transmission unit  6  for transmitting power to allow the transfer member  5  to operate is installed. 
     The transfer member  5  includes a rail  51  that is installed on the bottom of the inner portion of the case body  1  in a horizontal direction, a transfer rod  52  that is movably installed in the rail  51  and has both ends fixed to a belt of the power transmission unit  6 , and two hooks  53  that are installed in one side of the transfer rod  52  to have the IP  2  hooked thereto. 
     In particular, a protection cover (not shown) for protecting the transfer member  5  from the above elements installed inside the case body  1  is formed in the upper portion of the transfer member  5 . 
     The power transmission unit  6  includes a driving pulley  62  that is fixed to the driving axis of a motor  61 , a following pulley  65  that is connected to the driving pulley  62  via a first belt  63  and rotates and is connected to two roller shafts  64 , the roller shafts  64  that are installed in both sides of the inner portion of the case body  1  and are connected to the following pulley  65  and first and second pulleys  641  and  642 , and two second belts  66  that are wound around the first and second pulleys  641  and  642  of the roller shaft  64  and transfer a rotational force. 
     In more detail, when the motor  61  of the power transmission unit  6  operates according to a control signal of the controller  7 , the roller shafts  64  rotate in association with the operation of the motor  61 , the second belts  66  that are wound around the first and second pulleys  641  and  642  of the roller shaft  64  rotate, and the transfer rod  52  fixed to the second belts  66  is transferred. The IP  2  that is hooked on the hook  53  is transferred along with the transfer of the transfer rod  52 . 
     Meanwhile, the laser beam scanning unit  4  guides a laser beam generated from laser  3 . 
     The laser beam scanning unit  4  includes the swing mirror  41  that swings left and right according to power applied from the outside, and scans the laser beam generated from the laser  3 , a F-theta lens  42  that adjusts a focal distance of the laser beam deflected in the swing mirror  41 , and an auxiliary mirror  43  that reflects the laser beam which has passed through the F-theta lens  42  to a scanning region. 
     Referring to  FIGS. 4 and 5 , the swing mirror  411  includes a flow plate  411  having a mirror  411   a  fixed to the front surface of the flow plate  411 , two magnets  412  installed at both sides of the rear surface of the flow plate  411 , a fixing plate  413  installed to face the flow plate  411  by a predetermined space and having two coils  413   a  installed in the positions corresponding to the magnets  412 , and two springs  415  each connected to two connection rods  414  that protrude from both sides of the flow plate  411  and the fixing plate  413 . 
     In more detail, if power is applied to the left coil  413   a , a magnetic force is generated in the left coil  413   a , the magnet  412  installed in the position corresponding to the left coil  413   a  moves according to the magnetic force simultaneously with the contraction of the left spring  415 , and thus the flow plate  411  connected to the left spring  415  swings left. 
     To the contrary, if power is applied to the right coil  413   a , the right magnet  412  and the right spring  415  operate and thus the flow plate  411  swings right. 
     Two line scanning may be performed at a single swing of the swing mirror  41 . Adjustment of a swing width prevents laser from scanning an unnecessary region, which may increase a duty ratio (a ratio between a selection time applied to an electrode pattern and time, i.e., a cycle, for scanning all electrode patterns one time by a selection waveform) obtained by scanning the IP  2  with laser. The increase of the duty ratio can achieve a sufficient time for making laser staying on the IP 2 , which increases a swing speed of the swing mirror  41  and reduces scanning time of the IP 2 . 
     The F-theta lens  42  is in a semi-circular shape. A plane plate  421  is formed on the upper portion of the F-theta lens  42 , a plurality of screws are used to lock the F-theta lens  42  into the plane plate  421 , the F-theta lens  42  is fixed to the bottom of the case body  1 , and thus the F-theta lens  42  does not move. 
     The auxiliary mirror  43 , which is a general mirror, is installed near the F-theta lens  42  so as to reflect laser beam passing through the F-theta lens  42  onto a scan region, and changes an installation direction in view of a reflection region of the laser beam. 
     The reflection mirror  11  is installed in the entrance of the case body  1  and has the laser beam scanned by the laser beam scanning unit  4  reflected onto the IP  2  without emitting the laser beam to the outside. In particular, the reflection mirror  11  is installed to have an inclination angle of 45 degrees. 
     Referring to  FIG. 6 , the dichroic filter  12  transmits through the laser beam reflected by the reflection mirror  11  to be scanned on the IP  2  and reflects a blue wavelength light having photostimulated luminescence on the IP  2  by the scanning of the laser beam. 
     The dichroic filter  12  is fixed to the outer surface of a fixing plate  131  that fixes an optical fiber  13  which is a bundle of fibers, and is installed to have an inclination angle of 45 degrees with respect to light that is input into the optical fiber  13 . 
     The dichroic filter  12  allows a red wavelength light for scanning the IP  2  to reach the IP  2  by transmitting the red wavelength light therethrough, and transfer a blue wavelength light expressed in the IP  2  to the photo-multiplication tube  15  by reflecting the blue wavelength light. 
     The dichroic filter  12  can produce a substitution effect of the band-pass filter  14  by itself, and can increase an effect of preventing the red wavelength light from being transferred to the photo-multiplication tube  15  when the dichroic filter  12  is used with the band-pass filter  14 . 
     The optical fiber  13  transfers the blue wavelength light having photostimulated luminescence on the IP  2  to the band-pass filter  14 . 
     The optical fiber  13 , which is a bundle of fibers, has one side that is uniformly unfolded by the width of the IP  2  and is fixed to the fixing plate  131 , and another side that is fixed as a bunch and is inserted into the photo-multiplication tube  15 . 
     The band-pass filter  14  is installed between the optical fiber  13  and the photo-multiplication tube  15 , transmits the blue wavelength light therethrough and prevents the red wavelength light from transmitting therethrough in order to acquire the blue wavelength light transferred only through the optical fiber  13 . 
     In more detail, in order to acquire accurate image information, the photo-multiplication tube  15  must selectively acquire the blue wavelength light that is image information expressed by separating the red wavelength light used to scan the IP  2  and the blue wavelength light expressed on the IP  2 . Therefore, the band-pass filter  14  separates wavelengths. 
     The photo-multiplication tube  15  acquires and collects blue wavelength image signals transmitting through the band-pass filter  14  and amplifies images. 
     Meanwhile, the position detection sensors  16  are installed at both ends of the entrance of the case body  1  and detect positions where the laser beam is scanned. 
     In more detail, when laser swung by the swing mirror  41  is detected by the left position detection sensor  16 , it is recognized as a start of scanning, and when the laser is detected by the right position detection sensor  16 , it is recognized as an end of scanning. Thus, one line scanning is complete, subsequent line scanning starts right, when the laser is detected by the right position detection sensor  16 , it is recognized as a start of scanning, and when the laser is detected by the left position detection sensor  16 , it is recognized as an end of scanning. 
     When the laser beam is fully swung, a signal is detected by two sensors as shown in  FIG. 7 . 
     Referring to  FIG. 7 , T cycle is a cycle by which an image is obtained by a single mirror swing, L→R imaging indicates acquisition of an image signal when laser beam moves from left to right by a half swing of a mirror, R→L imaging indicates acquisition of an image signal when laser beam moves from right to left by a half swing of a mirror, R dead indicates dead time between an end of L→R imaging and a start of R→L imaging by using a right detection sensor, and L dead indicates dead time between an end of R→L imaging and a start of L→R imaging by using a left detection sensor. 
     A rising edge and a falling edge of a sensor are precisely measured by hardware logic in view of a high speed time. The measurement result is added to the end of corresponding image data and is transmitted to a PC. That is, an image for which scanning is complete may provide information about laser beam at the time of obtaining an image of a corresponding line at the end of each line along with the image. 
     Software performed in the PC receives the image information, calculates a start point and an end point of a physical image by utilizing the measurement information of the laser beam disposed at the end of a corresponding line, and adjusts inner image information to an actual physical position. 
     The controller  7  controls the operation of the laser  3 , the laser beam scanning unit  4 , the position detection sensors  16 , and the power transfer unit  6 . 
     The controller  7  controls the general operation of the apparatus for acquiring the digital X-ray image and transmits acquired image information to the PC. 
     If data processing is performed with regard to an image signal by using an A/D converter (not shown) for converting an analog image signal which is amplified by the photo-multiplication tube  15  into a digital signal, the image signal is connected to an output port of the controller  7  to display image data on the PC and a monitor. 
     Hereinafter, the relationships between the operations of the apparatus for acquiring the digital X-ray image will now be described. 
     When the laser  3  operates under the control of the controller  7 , laser beam generated by the laser  3  is radiated onto the swing mirror  41 . The swing mirror  41  which receives the laser beam swings fast left and right, the scanned laser beam is focused through the F-theta lens  42 , and is scanned to an entrance side of the IP  2  that is a scanning region by the reflection of the auxiliary mirror  43  through the F-theta lens  42 . 
     The transfer member  5  that receives power of the power transfer unit  6  operates and thus the IP  2  is transferred to the scanning region. 
     The laser beam scanned to the entrance side of the IP  2  is transmitted through the dichroic filter  12  which is inclined by 45 degrees, and is sent to the optical fiber  13  by reflecting the blue wavelength light of the IP  2 . 
     In addition to the blue wavelength light, an undesired red wavelength light is transferred through the optical fiber  13 , and is prevented from transmitting through the band-pass filter  14 . 
     As described above, image scanning of the IP  2  is complete. Meanwhile, when a laser beam swung by the swing mirror  41  is detected by a left sensor, it is recognized as a start of the image scanning, and when the laser beam is detected by a right sensor, it is recognized as an end of the image scanning. Both direction scanning of the IP  2  is continued by the two sensors and thus the IP  2  is entirely scanned. 
     Meanwhile,  FIG. 8  is a schematic perspective view of an apparatus for acquiring a digital X-ray image according to another embodiment of the present invention. Referring to  FIG. 8 , in the apparatus for acquiring the digital X-ray image of the present embodiment, the case body  1  includes the IP  2 . 
     The apparatus for acquiring the digital X-ray image that scans a laser beam onto the IP  2  included in the case body  1  and acquires an image signal from latent images accumulated by scanning radiation onto the IP  2  includes a laser beam scanning unit  4  guiding the laser beam generated from laser  3 , a reflection mirror  11  installed in one side of the interior of the case body  1  and having the laser beam scanned by the laser beam scanning unit  4  reflected onto the IP  2  without emitting the laser beam to the outside, a dichroic filter  12  transmitting through the laser beam reflected by the reflection mirror to be scanned on the IP  2  and reflecting a blue wavelength light having photostimulated luminescence on the IP  2  by the scanning of the laser beam, an optical fiber  13  transferring the blue wavelength light having photostimulated luminescence on the IP  2  to a band-pass filter, a band-pass filter  14  transmitting the blue wavelength light therethrough and preventing a red wavelength light from transmitting therethrough in order to acquire the blue wavelength light transferred through the optical fiber  13 , a photo-multiplication tube  15  acquiring and collecting blue wavelength image signals transmitting through the band-pass filter  14  and amplifying images, two position detection sensors  16  installed at both ends of one side of the interior of the case body  1  and detecting positions where the laser beam is scanned, a plurality of transfer members  5  installed inside the case body  1  and reciprocally transferring the IP  2  forward and backward, a power transmission unit  6  transmitting power to allow the transfer members  5  to operate, and a controller  7  controlling the operations of the laser  3 , the laser beam scanning unit  4 , the position detection sensors  16 , and the power transmission unit  6 . 
     The elements of the apparatus for acquiring the digital X-ray image of the present embodiment that includes the IP  2  have the same construction as those of the apparatus for acquiring the digital X-ray image of the previous embodiment, except for the arrangement of the IP  2 , the transfer members  5 , and the power transmission unit  6 . 
     The transfer members  5  are fixed in a length direction of a chain  68  of the power transmission unit  6  and are rectangular-shaped and are bent in the shape of “           ” from both ends thereof in order to guide transfer of the IP  2 .
     The power transmission unit  6  includes a driving pulley  62  that is fixed to the driving axis of a motor  61 , a following pulley  65  that is connected to the driving pulley  62  via a belt and rotates and is connected to a plurality of chain shafts  67  installed inside the case body  1 , first and second sprockets  671  and  672  installed in both ends of the chain shafts  67 , respectively, and the chain  68  fastened to the first and second sprockets  671  and  672 . 
     A diameter of the first sprocket  671  is smaller than that of the second sprocket  672  so that the first sprocket  671  is not limited to a space where the laser beam scanning unit  4  is installed. 
     An apparatus for acquiring a digital X-ray image according to the present invention acquires a digitalized X-ray image by using a reusable IP, which does not need a film, a developing solution, and a developer which are consumables, and stores the digitalized X-ray image on a storage medium, such as a hard disc or a CD, which does not need a huge scale of a storage space as needed for use of the film. 
     Also, the apparatus displays the acquired image on a computer monitor, adjusts brightness and luminance of the displayed image in various ways by provided software, and makes the displayed image to be always viewed in an optimal state, thereby reducing re-radiation due to an improper X-ray radiation. 
     Also, the apparatus is easy for carrying in a cassette way, which can be easily installed and carried irrespective of a place. 
     Also, the apparatus can secure sufficient time to make laser stay on an IP, which increases a swing speed of a swing mirror and reduces a time for wholly scanning the IP. 
     While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.