JP2007079242A - Erase beam irradiating panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the efficiency of using erase beam, in an erase beam irradiating panel for irradiating the erase beam to a radiation image detection panel. <P>SOLUTION: The elimination light irradiating panel has an erase beam emitting area 310 emitting the erase beam and a reading light passing area 320 through which each linear reading light Lr to be image-formed through an image-forming means 400 passes. The erase beam irradiating panel is arranged between the image-forming means 400 and a radiation image detection panel 100. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an erasing light irradiation panel for irradiating erasing light for erasing an afterimage of a radiographic image left on a radiographic image detection panel.

  Conventionally, a latent image charge indicating the radiation image is accumulated upon exposure to radiation carrying the radiation image of the subject, and then the radiation image is subjected to line-sequential scanning of linear reading light extending linearly. A radiation image recording / reading apparatus including a radiation image detection panel from which an image signal indicating the above is read is used for taking a medical radiation image, and various types of devices have been proposed.

  The radiographic image recording / reading apparatus includes an imaging means for forming linear light for reading on a linear area on the radiographic image detection panel when the radiographic image recorded on the radiographic image detection panel is read, and the reading The thing using the light emission panel which has arrange | positioned the electroluminescent element (EL element) which generate | occur | produces the linear light for use is known (refer patent document 1). Note that the EL element is an element that directly converts electric energy into light energy by recombining electrons and holes injected by applying an electric field in an organic light emitting layer.

  The light-emitting panel is disposed to face the radiation image detection panel with the imaging means interposed therebetween, and sequentially emits reading linear light extending linearly from different linear regions. Each reading linear light emitted from the light emitting panel is sequentially imaged in different linear areas on the radiation image detection panel through the imaging means. From the radiation image detection panel that has undergone line-sequential scanning of the reading linear light, an image signal indicating the radiation image recorded in the linear region in the radiation image detection panel is read out.

In the radiation image recording / reading apparatus as described above, after the radiation image is read from the radiation image detection panel, the erasing light is simultaneously irradiated on the entire surface of the radiation image detection panel and the radiation left on the radiation image detection panel is left. The afterimage of the image is erased. The wavelength of the erasing light is different from the wavelength of the reading linear light, and the reading linear light generating EL element and the erasing light generating EL element are both arranged on the light emitting panel. A light emitting panel that emits linear light and erasing light at different timings has also been studied.
JP 2000-162726 A

  The light-emitting panel that emits the reading linear light and the erasing light is excellent in reducing the size of the apparatus. However, it is not necessary to pass the erasing light that simultaneously irradiates the entire surface of the radiation image detection panel through the imaging means. Thus, when the erasing light is passed through the imaging means, the light quantity of the erasing light is attenuated. Therefore, there is a problem that the amount of erasing light generated from the light emitting panel has to be larger than the amount of light required for erasing the afterimage. Further, increasing the amount of the erasing light reduces the life of the erasing EL element. The above problem is not limited to the case where the erasing light is emitted from the EL element for the erasing light, but is a problem that generally arises when the erasing light is irradiated onto the radiation image detection panel through the imaging means.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an erasing light irradiation panel capable of increasing the use efficiency of erasing light.

  The erasing light irradiating panel of the present invention receives a radiation carrying a radiation image of a subject, accumulates latent image charges indicating the radiation image, and then reads a linearly imaged image formed through an imaging means. An erasing light for erasing an afterimage of the radiation image remaining on the radiation image detection panel for a radiation image detection panel from which an image signal indicating the radiation image is read by receiving a line sequential scanning of the linear light An erasing light irradiating panel that irradiates the erasing light, and is disposed between the imaging means and the radiation image detection panel, and an erasing light generating area that emits erasing light, and each reading linear light that is imaged through the imaging means And a reading light passage region through which the light passes.

  The linear scanning of the reading linear light means that the linear linear reading light is sequentially irradiated to different linear regions on the radiation image detection panel.

  The reading light passage region may be a hole that penetrates the erasing light generation panel. Further, the reading light passage region may be formed of a member that is transparent to the reading linear light.

  The erasing light irradiation panel may be laminated on the imaging means.

  The imaging means can be a gradient index lens array or a microlens array.

  The erasing light irradiation panel of the present invention is disposed between the imaging means and the radiation image detection panel on which the reading linear light is imaged. The erasing light generation region for emitting erasing light, and the radiation image through the imaging means. Since the reading light passing region for passing each reading linear light to be imaged on the detection panel is provided, the erasing light is irradiated on the radiation image detecting panel without passing the erasing light through the imaging means. Since the attenuation of the amount of erasing light caused by passing through the imaging means can be reduced, the use efficiency of erasing light can be increased. Further, the use efficiency of the erasing light can be increased, so that the light quantity of the erasing light can be reduced, and thereby the life of the erasing light irradiation panel can be extended.

  Further, if the reading light passage region is a hole penetrating the erasing light irradiation panel, the amount of light when reading linear light to be imaged on the radiation image detection panel passes through the erasing light irradiation panel is reduced. Can be more reliably suppressed.

  Embodiments of a radiation image recording / reading apparatus to which an erasing light irradiation panel of the present invention is applied will be described below with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of an erasing light irradiation panel mounted on a radiation image recording / reading apparatus, and FIG. 2 is an enlarged part of a cross section obtained by cutting the radiation image recording / reading apparatus along a plane parallel to the XZ plane. FIG.

  As shown in the figure, the radiation image recording / reading apparatus is exposed to radiation Lx carrying the radiation image of the subject 1 emitted from the radiation source 5 and accumulates a latent image charge indicating the radiation image. A radiation image detection panel 100 that receives line sequential scanning of linearly reading linear light Lr that is imaged through an imaging panel 400 that is an imaging means, and that reads out an image signal indicating the radiation image, and the radiation A reading light scanning panel 200 that linearly scans the image detection panel 100 with the reading linear light Lr, and an afterimage of the radiation image remaining after the radiation image is read from the radiation image detection panel 100 are erased. And an erasing light irradiation panel 300 of the present invention for irradiating the radiation image detection panel 100 with the erasing light Ls for this purpose.

  As the imaging panel 400, it is possible to adopt a flat refractive index distribution type lens array in which a large number of gradient index lenses are arranged, a flat micro lens array in which a large number of micro lenses are arranged, or the like. it can.

  The erasing light irradiation panel 300 is disposed between the imaging panel 400 and the radiation image detection panel 100 on which the reading linear light Lr that has passed through the imaging panel 400 is imaged. An erasing light generation region 310 that emits light, and a reading light passage region 320 through which each reading linear light Lr that forms an image through the imaging panel 400 passes. Here, the reading light passage region 320 is a hole that penetrates the erasing light irradiation panel 300, but may be formed of a transparent member such as glass or acrylic that transmits the reading linear light Lr.

  Each element of the radiation image detection panel 100, the reading light scanning panel 200, the erasing light irradiation panel 300, and the imaging panel 400 constituting the radiation image recording / reading apparatus is exposed to radiation carrying a radiation image. From the side, the radiation image detection panel 100, the erasing light irradiation panel 300, the imaging panel 400, and the reading light scanning panel 200 are arranged in this order.

  The reading light scanning panel 200 and the erasing light irradiation panel 300 can be light emitting panels that employ an EL (electroluminescence) light emitting method.

  Hereinafter, each of the radiation image detection panel 100, the reading light scanning panel 200, the erasing light irradiation panel 300, and the imaging panel 400 will be described in detail.

  First, the radiation image detection panel 100 will be described. As shown in FIG. 1, the radiation image detection panel 100 is a so-called optical readout type radiation image detection panel as disclosed in, for example, Japanese Patent Application Laid-Open No. 2000-284056, and includes a first electrode layer 11, The recording conductive layer 12, the charge transport layer 13, the reading conductive layer 14, the second electrode layer 15, and the insulating layer 17 are laminated in this order.

  The first electrode layer 11 is in an electrically insulated state and transmits radiation carrying a radiation image exposed to the radiation image detection panel 100. The recording conductive layer 12 is made of amorphous selenium, for example, and exhibits electrical conductivity and generates charge pairs upon exposure to radiation, which is a recording electromagnetic wave. The charge transport layer 13 acts as a substantially insulator for negative charges, and acts as a conductor for positive charges. The reading conductive layer 14 is made of, for example, amorphous selenium, and exhibits conductivity and generates a charge pair when irradiated with the reading linear light Lr. A second electrode layer 15 having a plurality of linear electrodes 16 extending in the direction of the arrow X in the drawing is laminated on the reading conductive layer 14. The second electrode layer 15 is insulated by the insulating layer 17.

  A power storage unit 19 is formed at the interface between the recording conductive layer 12 and the charge transport layer 13. That is, when electrons generated in the recording conductive layer 12 try to move to the second electrode layer 15 side by an electric field formed between the first electrode layer 11 and the second electrode layer 15, The movement is restricted by the transport layer 13. Accordingly, in the power storage unit 19, charges corresponding to the exposure dose of the radiation carrying the radiation image are accumulated as latent image charges, whereby the radiation image is recorded.

  Here, when a radiation image is recorded on the radiation image detection panel 100, a high voltage is applied between the first electrode layer 11 and the second electrode layer 15 from the signal acquisition unit 50. Then, a negative charge is charged on the first electrode layer 11 side, and a positive charge is charged on the second electrode layer 15 side. Next, when radiation carrying a radiation image is irradiated from the first electrode layer 11 side, positive and negative charge pairs are generated in the recording conductive layer 12 in accordance with the radiation exposure amount. Among them, the holes of the charge pair move to the first electrode layer 11 side, and form an image with the negative charge of the first electrode layer 11 and disappear. On the other hand, the electrons of the charge pair move toward the first electrode layer 11, but the movement is limited by the charge transport layer 13. As a result, a radiation image is recorded in the power storage unit 19 as a latent image charge.

  When reading the radiation image recorded in the power storage unit 19, the reading linear light Lr having a constant light amount emitted from the reading light scanning panel 200 and extending in the direction of the arrow Y in the figure is the imaging panel 400 and the erasing light irradiation panel 300. Then, the radiation image detection panel 100 is sequentially scanned toward the second electrode layer 15 side. The scanning direction in which the reading linear light Lr is sequentially scanned is an arrow X direction in the figure. When a charge pair is generated in the read conductive layer 14 that has been irradiated with the read linear light Lr, the holes of the generated charge pair pass through the charge transport layer 13 and negative charges accumulated in the power storage unit 19. Forms an image and disappears. On the other hand, the electrons of the charge pair move toward the second electrode layer 15 and form an image with positive charges. Then, when electrons and positive charges are combined in the second electrode layer 15, a current passing through the linear electrode 16 flows. When the signal acquisition unit 50 detects this change in current, an image signal indicating a radiation image is read.

  Next, the reading light scanning panel 200 will be described.

  Hereinafter, the reading light scanning panel 200 will be described with reference to FIGS. 1 and 2.

  The reading light scanning panel 200 created using the EL element emits reading linear light Lr made of blue light to the radiation image detection panel 100.

  The reading light scanning panel 200 is formed by laminating a cathode 22, a reading light emitting layer 24, and an anode 23 in this order. The anode 23 is a light-transmitting conductive layer such as an ITO film, and is formed on a light-transmitting substrate such as a glass substrate, and a plurality of linear electrodes arranged in stripes extending in the Y direction in the figure. 23D. On the other hand, the cathode 22 may be a light-transmitting conductive layer similar to that described above, or may have a conductive layer made of aluminum or the like.

  The structure in which the cathode 22, the reading light emitting layer 24, and the anode 23 are laminated in this order includes, for example, a laminated structure of a cathode, a light emitting layer, and an anode, a laminated structure of a cathode, a hole transport layer, a light emitting layer, and an anode, And a laminated structure of a cathode, a hole transporting layer, a light emitting layer, an electron transporting layer, an electron injection layer, and an anode.

  The cathode 22 and the anode 23 are electrically connected to the drive power supply unit 30, and the drive power supply unit 30 supplies drive power for causing the cathode 22 and the anode 23 to emit the reading linear light Lr. Specifically, the positive electrode of the drive power supply unit 30 is connected to each linear electrode 23 </ b> D of the anode 23 via the switching element 21, and the negative electrode of the drive power supply unit 30 is connected to the cathode 22. The operation of the switching element 21 is controlled by the light emission control unit 40.

  When the reading light beam Lr is scanned line-sequentially from the reading light scanning panel 200, the linear electrodes lined up in the scanning direction (arrow X direction in the figure) by sequentially turning on and off the switching element 21 under the control of the light emission control unit 40. A voltage is sequentially applied to 23D. Then, the reading linear light Lr is sequentially emitted from the reading light emitting layer 24 sandwiched between the linear electrode 22D to which the driving voltage is applied and the cathode 22, and the reading light scanning panel 200 reads the reading linear light. Line sequential scanning of the light Lr is executed.

  Each reading linear light Lr emitted from the reading light scanning panel 200 is propagated to the radiation image detection panel 100 through the imaging panel 400 and the erasing light irradiation panel 300. Here, each reading linear light Lr imaged through the imaging panel 400 extends in the Y direction in the drawing on the radiation image detection panel 100 through the reading light passage region 320 in the erasing light panel 300. An image is formed on a linear region.

  Next, the erasing light irradiation panel 300 of the present invention will be described.

  FIG. 3 is a diagram showing a state in which the erasing light irradiation panel 300 and the imaging panel 400 are viewed from the radiation image detection panel 100 side.

  Hereinafter, the erasing light irradiation panel 300 will be described with reference to FIG. 3 and FIGS. 1 and 2 described above.

  After the radiation image is read from the radiation image detection panel 100, the erasing light irradiation panel 300 erases the residual image of the radiation image remaining on the radiation image detection panel 100. For example, orange light can be used as erasing light.

  Each reading light passage region 320 that is a hole penetrating the erasing light irradiation panel 300 is arranged corresponding to each gradient index lens 410 constituting the imaging panel 400, and is parallel to the arrow Z direction in the figure. The optical axis 410C of the gradient index lens 410 coincides with the central axis 320C of the reading light passage region 320.

  The erasing light generation region 310 of the erasing light irradiation panel 300 has a three-layer structure in which a cathode, a light emitting layer, and an anode are laminated in this order, similar to the reading light scanning panel 200. Can be adopted. The cathode 32 of the erasing light generation region 310 is electrically connected directly to the driving power supply unit 30, and the anode 33 of the erasing light generation region 310 is connected to the driving power supply unit 30 via the switching element 42. The driving power supply unit 30 supplies driving power for causing the cathode 32 and the anode 33 to emit the reading linear light Lr. Specifically, when the switching element 42 is turned on, a voltage is simultaneously applied to the entire cathode 32 and the entire anode 33, that is, the entire erase light generation region 310. When the switching element 42 is turned on and a driving voltage is applied between the cathode 32 and the anode 33, the erasing light Ls is emitted from the erasing light generation region 310.

  The residual image of the radiation image remaining on the radiation image detection panel 100 is erased by irradiating the radiation image detection panel 100 with the erasing light Ls, so that the radiation image detection panel 100 can be used again for recording and reading of the radiation image. be able to.

  Here, the attenuation of the light amounts of the erasing light Ls and the reading linear light Lr will be described in detail with reference to FIGS. 4 (a) and 4 (b). 4A is a diagram showing a change in the amount of light when the erasing light emitted from the erasing light irradiation panel propagates through the imaging panel, and FIG. 4B is an erasing light emitted from the erasing light irradiation panel. It is a figure which shows the change of the light quantity of the erasing light in the case of a system different from the present invention in which light propagates through the imaging panel.

  As shown in FIG. 4A, the erasing light Ls having the light quantity Q2 emitted from the erasing light irradiation panel 300 reaches the radiation image detection panel 100 while maintaining the light quantity Q2. Further, the reading linear light Lr having the light amount P1 emitted from the reading light scanning panel 200 passes through the imaging panel 400, and the light amount is attenuated from the light amount P1 to the light amount P2. However, when the reading linear light Lr passes through the erasing light irradiation panel 300, the light amount does not attenuate and reaches the radiation image detection panel 100 while maintaining the light amount P2.

  On the other hand, as shown in FIG. 4B, in the system employing the light emitting panel 500 different from the present invention which also serves as the reading light scanning panel 200 and the erasing light irradiation panel 300, the light is emitted from the light emitting panel 500. The erasing light Ls having the light quantity Q1 passes through the imaging panel 400, and the light quantity attenuates from the light quantity Q1 to the light quantity Q2 and reaches the radiation image detection panel 100. Further, the reading linear light Lr having the light amount P1 emitted from the light emitting panel 500 passes through the imaging panel 400 and the light amount is attenuated from the light amount P1 to the light amount P2, and reaches the radiation image detection panel 100. That is, in order to set the light quantity of the erasing light Ls reaching the radiation image detection panel 100 to the light quantity Q2, the light quantity of the erasing light Ls emitted from the light emitting panel 500 must be set to the light quantity Q1 larger than the light quantity Q2. The use efficiency of the erasing light Ls is lower than in the case of.

  As described above, according to the present invention, the erasing light Ls can be propagated to the radiation image detection panel without passing through the imaging means, so that the use efficiency of the erasing light can be enhanced. Thereby, the amount of erasing light can be reduced, and the lifetime of the erasing light irradiation panel can be extended.

  Note that the reading linear light Lr that forms an image on the radiation image detection panel 100 through the imaging panel 400 that is the imaging means passes through the reading light passage region 320 of the erasing light irradiation panel 300. After passing through the imaging panel 400, the light Lr is propagated to the radiation image detection panel 100 without causing light quantity attenuation. Therefore, the use efficiency of the read linear light Lr is hardly reduced by the technique for increasing the use efficiency of the erasing light.

  Further, the erasing light irradiation panel includes a stripe-shaped erasing light generation region formed along a plurality of linear electrodes extending in the erasing light irradiation panel and the stripe-shaped erasing light generation regions adjacent to each other. It may have a reading light passage area formed.

  The erasing light irradiation panel includes a lattice-like erasing light generation region formed along linear electrodes extending vertically and horizontally in the erasing light irradiation panel, and a region surrounded by the lattice-like erasing light generation region. It may have a reading light passage area formed.

  Further, the erasing light irradiation panel may be configured such that the entire erasing light irradiation panel is made of a member that is transparent to the linear light for reading. That is, the reading light passage region may be a region that also serves as the erasing light generation region, or the reading light passage region and the erasing light generation region may be formed as different regions.

  FIG. 5 is a diagram showing a configuration in which an erasing light irradiation panel is stacked on an imaging panel.

  As shown in FIG. 5, the erasing light irradiation panel 300 can be stacked on the imaging panel 400. In such a case, the erasing light irradiation panel 300 can be printed and formed on the imaging panel 400.

  Furthermore, when the radiation image detection panel 100 is irradiated with the reading linear light Lr to read the radiation image, the electrode of the erasing light irradiation panel 300 is grounded, and the erasing light irradiation panel 300 is attached to the radiation image detection panel 100. You may make it utilize as a shield board. Accordingly, it is possible to prevent electrical noise from being mixed into the image signal when the image signal is detected from the latent image charge accumulated in the radiation image detection panel 100.

The figure which shows schematic structure of the erasing light irradiation panel mounted in the radiographic image recording and reading apparatus of embodiment of this invention Expanded sectional view showing a part of the radiation image recording / reading apparatus in an enlarged manner Diagram showing erasing light irradiation panel 4A is a diagram showing a change in the amount of erasing light propagating without passing through the imaging panel, and FIG. 4B is a diagram showing a change in the amount of erasing light propagating through the imaging panel. The figure which shows the structure which laminated the erasing light irradiation panel on the image formation panel

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Subject 5 Radiation source 100 Radiation image detection panel 200 Reading light scanning panel 300 Erase light irradiation panel 310 Erase light generation area 320 Reading light passage area 400 Imaging means Lx Radiation Lr Read linear light Ls Erase light

Claims (5)

The latent image charge representing the radiation image is accumulated upon exposure of radiation carrying the radiation image of the subject, and thereafter, scanning of the linear light for reading that extends linearly through the imaging means is performed. An erasing light irradiating panel for irradiating an irradiating light for erasing an afterimage of the radiation image remaining on the radiation image detecting panel to the radiation image detecting panel that receives the image signal indicating the radiation image. And
An erasing light generation region that is disposed between the imaging means and the radiation image detection panel and emits the erasing light; and a reading light passage region through which each linear light for reading formed through the imaging means passes. An erasing light irradiation panel comprising:   The erasing light irradiation panel according to claim 1, wherein the reading light passage region is a hole that penetrates the erasing light generation panel.   3. The erasing light irradiation panel according to claim 1, wherein the erasing light irradiation panel is laminated on the imaging means.   4. The erasing light irradiation panel according to claim 1, wherein the imaging means is a gradient index lens array.   4. The erasing light irradiation panel according to claim 1, wherein the image forming means is a microlens array.

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