Patent Publication Number: US-2023165107-A1

Title: Flat panel and scanning device comprising the same

Description:
BACKGROUND 
     Field 
     Disclosed herein are a scanning device which generates a digital image signal in relation to a print out, and a flat panel with which the scanning device is provided. 
     Description of Related Art 
     Scanning devices generate a digital image signal in relation to a print out. A scanning device generates a digital image signal, based on results of the measurement of an amount of light reflected from a printout put on a flat transparent support board for each pixel area. 
     The scanning device is usually implemented in a large size, difficult to carry, and causes user inconvenience because users need to manually place an object to be scanned on the flat transparent support board one by one, resulting in limitations on its availability. 
     Currently, it is relatively easy to manufacture a panel where light sensing elements are integrated. Accordingly, a portable scanning device implemented as a flat plate is on the market. 
     In an example, a flat plate-shaped scanning device is provided with a flat panel including a light emitting element irradiating light in each pixel area, and a light sensing element sensing an amount of light in each pixel area. The flat plate-shaped scanning device has become relatively lightweight and small. In the case of a flat plate-shaped scanning device, users control on/off of scanning operation in a state in which the scanning device is placed on an object to be scanned such that a digital image signal in relation to the object to be scanned is generated relatively easily. 
     DISCLOSURE 
     Technical Purpose 
     A flat plate-shaped scanning device can be provided with a flat transparent panel to improve convenience and allow a user to control scanning operation while the user directly checks an object to be scanned. 
     The flat transparent panel includes a light transmitting area that is arranged in a way that a light transmitting area alternates with a pixel area. A light emitting element and a light sensing element corresponding to each pixel area are disposed. However, the light transmitting area transmits light with no light emitting element and light sensing element therein. Accordingly, the user can recognize an object disposed under the flat panel and aware that the flat panel is transparent. 
     In the case of a flat transparent panel, the light sensing element of each pixel area can sense light that is not generated in each pixel area, through the light transmitting area. 
     Additionally, in the case of a flat transparent panel, light of some pixel areas can be delivered to the light sensing element of an adjacent pixel area through the light transmitting area. 
     In a flat panel that provides the function of displaying an image using the light emitting element of each pixel area, the light emitting element&#39;s light can be incident directly to a light sensing sensor in a state in which the light emitting element&#39;s light is not reflected from an object to be scanned. 
     As described above, light having various paths can be incident to the light sensing element, resulting in deterioration of the accuracy of a detection signal generated by the light sensing element. 
     According to the present disclosure, a flat panel and a scanning device including the same that can ensure improvement in the accuracy of a detection signal generated by the light sensing element is provided to solve the above problems. 
     Aspects according to the present disclosure are not limited to the above ones, and other aspects and advantages that are not mentioned above can be clearly understood from the following description and can be more clearly understood from the embodiments set forth herein. Additionally, the aspects and advantages in the present disclosure can be realized via means and combinations thereof that are described in the appended claims. 
     Technical Solution 
     In one embodiment, a flat panel may include a plurality of pixel areas, each of the plurality of pixel areas, including a light emitting area emitting light, a light transmitting area being adjacent to the light emitting area and transmitting light, and a light sensing area constituting a portion of the light emitting area and sensing light, may include a sensing array disposed on a first support board and including a light sensing element corresponding to the light sensing area of each of the plurality of pixel areas, a micro lens disposed between the first support board and the light sensing element, a first light shielding wall disposed between the first support board and the light sensing element and corresponding to an edge of the light sensing area of each of the plurality of pixel areas, and a light emitting array disposed between the sensing array and a second support board and including a light emitting element corresponding to the light emitting area of each of the plurality of pixel areas. 
     With the micro lens corresponding to the light sensing area of each pixel area, light rays reflected from an object to be scanned disposed below the first support board may be converged by the micro lens and then incident to the light sensing element, leading to an increase in the amount of light rays incident to the light sensing element among the light rays reflected from the object to be scanned. 
     The first light shielding wall corresponding to the edge of the light sensing area of each pixel area may block light, which is not generated and reflected in each pixel area, from being delivered to the micro lens through the light transmitting area. 
     First and second electrodes of the light emitting element may be made of a transparent conductive material or a semitransparent conductive material in each. Additionally, the light emitting array may further include a light shielding-reflecting layer corresponding to a portion of the light emitting area of each of the plurality of pixel areas and disposed under the first electrode. 
     With the first and second electrodes and the light shielding-reflecting layer, the light emitting element&#39;s light may be emitted to one side, i.e., toward the second support board in a portion of the light emitting area of each pixel area, and the light emitting element&#39;s light may be emitted to both sides, i.e., toward the first support board and the second support board in the remaining portion of the light emitting area of each pixel area. 
     Since the light shielding-reflecting layer is disposed between the light emitting element and the light sensing element, the light emitting element&#39;s light emitted toward the first support board may be prevented from being directly incident to the light sensing element. 
     Since the flat panel includes the plurality of pixel areas including the light transmitting area respectively, the flat panel may look transparent. Further, the flat panel may ensure improvement in the accuracy of a detection signal generated by the light sensing element with the micro lens, the first light shielding wall and the light shielding-reflecting layer. 
     The flat panel in one embodiment may further include a second light shielding wall that surrounds the light emitting area of each of the plurality of pixel areas. 
     The second light shielding wall may block a light path between adjacent pixel areas, leading to improvement in the accuracy of a detection signal generated by the light sensing element. 
     The flat panel in one embodiment may further include an electromagnetic shielding pattern disposed between the sensing array and the light emitting array. 
     The electromagnetic shielding pattern may block signal interference between the sensing array and the light emitting array. 
     In another embodiment, a scanning device is provided with the flat panel described above. 
     Technical Effects 
     A flat panel in several embodiments includes a plurality of pixel areas including a light transmitting area transmitting light respectively such that the flat panel looks transparent. 
     The flat panel in each embodiment includes a first light shielding wall corresponding to an edge of a light sensing area of each pixel area. Accordingly, light, which is not reflected from an object to be scanned disposed under a first support board, in the light sensing area of each pixel area, may be prevented from being incident to a light sensing element of each pixel area. 
     The flat panel in each embodiment further includes a light shielding-reflecting layer disposed between a light emitting element and a light sensing element and corresponding to a portion of a light emitting area. Accordingly, light incident from the light emitting element directly to the light sensing element may be blocked. 
     The flat panel in one embodiment further includes a second light shielding wall that surrounds the light emitting area of each pixel area. Thus, a path, in which light generated in some pixel areas is delivered to the light sensing element of an adjacent pixel area through the light transmitting area of each pixel area, may be blocked. 
     Thus, the flat panel looks transparent, and the accuracy of a detection signal generated by the light sensing element may improve. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a view showing an example in which a flat panel-shaped scanning device is used. 
         FIG.  2    is a view showing examples of a flat panel-shaped scanning device. 
         FIG.  3    is a view showing a flat panel and a panel driver. 
         FIG.  4    is a view showing an example of an equivalent circuit corresponding to a light emitting area in  FIG.  3   . 
         FIG.  5    is a view showing an example of an equivalent circuit corresponding to a light sensing area in  FIG.  3   . 
         FIG.  6    is a view showing a flat panel in  FIGS.  1  and  2   . 
         FIG.  7    is a view showing a portion of the flat panel in  FIG.  6   . 
         FIG.  8    is a view showing portion A of  FIG.  7    in one embodiment. 
         FIG.  9    is a view showing a cross section along I-I′ of  FIG.  8   . 
         FIG.  10    is a view showing portion B of  FIG.  9   . 
         FIG.  11    is a view showing portion C of  FIG.  9   . 
         FIG.  12    is a view showing an example of light paths of any two adjacent pixel areas of a flat panel in a first embodiment. 
         FIG.  13    is a view showing portion A of  FIG.  7    in a second embodiment. 
         FIG.  14    is a view showing a cross section along II-II&#39; of  FIG.  13   . 
         FIGS.  15  to  18    are views showing an example of a plan view of single-layer patterns included in a second light shielding wall in  FIG.  14   . 
         FIG.  19    is a view showing an example of light paths of any two adjacent pixel areas of a flat panel in the second embodiment. 
         FIG.  20    is a view showing a cross section along II-II′ of  FIG.  13    in a third embodiment. 
     
    
    
     DETAILED DESCRIPTIONS 
     The above-described aspects, features and advantages are specifically described hereafter with reference to the accompanying drawings such that one having ordinary skill in the art to which the present disclosure pertains can easily implement the technical spirit of the disclosure. In the disclosure, detailed description of known technologies in relation to the disclosure is omitted if it is deemed to make the gist of the disclosure unnecessarily vague. Below, preferred embodiments according to the disclosure are specifically described with reference to the drawings. In the drawings, identical reference numerals can denote identical or similar components. 
     A scanning device provided with a flat panel in each embodiment is described with reference to  FIGS.  1  to  5   . 
       FIG.  1    is a view showing an example in which a flat panel-shaped scanning device is used.  FIG.  2    is a view showing examples of a flat panel-shaped scanning device.  FIG.  3    is a view showing a flat panel and a panel driver.  FIG.  4    is a view showing an example of an equivalent circuit corresponding to a light emitting area in  FIG.  3   .  FIG.  5    is a view showing an example of an equivalent circuit corresponding to a light sensing area in  FIG.  3   . 
     As illustrated in  FIG.  1   , a scanning device  10  may include a flat panel  100  that performs scanning, and a side part  200  that is fixed to an edge of at least one side of the flat panel  100 . 
     The scanning device  10  may perform a scanning operation based on a user&#39;s input, in a state of being put on a flat object  20  to be scanned such as a printout and the like. The scanning operation may involve irradiating light to an object to be scanned  20  and sensing an amount of light reflected from the object to be scanned  20  by each pixel area, and based on a detection signal corresponding to the amount sensed by each pixel area, generating a digital image signal corresponding to the object to be scanned  20 . 
     To this end, the flat panel  100  may include a lighting emitting element and a light sensing element that correspond to each pixel area. 
     Additionally, the flat panel  100  may be a transparent panel such that the user controls the scanning operation while the user recognizes the object to be scanned  20  directly. That is, in the flat panel  100 , each pixel area may include a light emitting area that emits light, a light sensing area that senses light, and a light transmitting area that transmits light. 
     Further, in each pixel area of the flat panel  100 , the light sensing element may be disposed closer to the object to be scanned  20  than the light emitting element, to reduce a loss of the light reflected from the object to be scanned  20  in a path to the light sensing element. That is, under the assumption that the flat panel  100  is placed on an object to be scanned  20 , the light emitting element may be disposed on the light sensing element. 
     The flat panel  100  is described hereafter specifically with reference to the accompanying drawings. 
     A circuit board for driving the flat panel  100  and the like is stored in the side part  200 . Since the side part  200  is not an area in which scanning operation is performed, the side part may be further used as an interface for receiving the user&#39;s control input, a supporter of the flat panel  100  and the like. 
     As illustrated in  FIG.  2 ( a ) , the side part  201  may be disposed in parallel with one of the relatively long sides of the edges of the flat panel  100  having a rectangle shape, for example. 
     However, the position of the side part  200  may vary depending on the user&#39;s convenience and the flat panel  100 &#39;s strength. 
     That is, the side part  202 , as illustrated in  FIG.  2 ( b ) , may be disposed in parallel with each of the two relatively long sides of the edges of the flat panel  100  having a rectangle shape. 
     Alternatively, the flat panel  100 , as illustrated in  FIG.  2 ( c ) , may be made of a soft material that can bend, and the bent flat panel  100  may be further stored in the side part  203 . 
     Alternatively, the side part  204 , as illustrated in  FIG.  2 ( d ) , may be disposed in parallel with each of the four sides forming the edges of the flat panel  100  having a rectangle shape. That is, the side part  204  may be disposed to surround the flat panel  100 . 
     The panel driver implemented as a circuit board (not illustrated) stored in the side part ( 200  in  FIG.  1   ) provides a driving signal for driving the light emitting element of the flat panel  100  and reads out a detection signal of the light sensing element. 
     The flat panel  100 , as illustrated in  FIG.  3   , has a plurality of pixel areas (PA) that is arranged in a matrix form in an active area where scanning is performed. 
     Each of the plurality of pixel areas PA includes a light emitting area EA that emits light, a light transmitting area TA that transmits light, and a light sensing area SA that senses an amount of light. The light sensing area SA is used to sense an amount of light that is emitted from the light emitting area EA and reflected from an object to be scanned ( 20  in  FIG.  1   ), and constitutes a portion of the light emitting area EA. 
     The panel driver  210 ,  220 ,  230 ,  240 ,  250  may provide a gate signal and a data signal for driving a light emitting element disposed in the light emitting area EA, and a scan signal for selecting a light sensing element that reads out a detection signal, among light sensing elements corresponding to each light sensing area SA, to the flat panel  100 , and receive a detection signal of a selected light sensing element. 
     The flat panel  100  further includes a gate line GL for providing a gate signal (GS in  FIG.  4   ) to the plurality of pixel areas PA, a data line DL for providing a data signal (Vdata in  FIG.  4   ) to the plurality of pixel areas PA, a scan line SL for providing a scan signal (SS in  FIG.  5   ) to the plurality of pixel areas PA, and a read-out line ROL for receiving a detection signal (Rdata in  FIG.  5   ) from each of the plurality of pixel areas PA. 
     The panel driver include a gate driver  210  that provides a gate signal to the gate line GL of the flat panel  100 , a data driver  220  that provides a data signal to the data line DL of the flat panel  100 , a timing controller  230  that controls a drive timing of the gate driver  210  and a drive timing of the data driver  220 , a scan driver  240  that provides a scan signal to the scan line SL of the flat panel  100 , and a read-out driver  250  that receives a detection signal from the read-out line SL of the flat panel  100 . 
     The timing controller  230  may further control a drive timing of the scan driver  240  and a drive timing of the read-out driver  250 . 
     In an example, the timing controller  230  may control the gate driver  210  and the data driver  220  such that the light emitting areas EA of all the pixel areas PA emit light during a predetermined light-emitting period, based on the user&#39;s scanning control input, and may control the scan driver  240  and the read-out driver  240  such that receive a detection signal corresponding to an amount of light incident to the light sensing areas SA of all the pixel areas PA during a sensing period after the predetermined light emitting period. 
     In another example, in a flat panel  100  that provides the function of displaying an image, the timing controller  230  realigns digital video data RGB input from the outside according to resolution of the active area, and provides the realigned digital video data RGB′ to the data driver  220 . 
     Additionally, the timing controller  230  provides a data control signal DDC for controlling an operation timing of the data driver  220 , and a gate control signal GDC for controlling an operation timing of the gate driver  210 , based on timing signals such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a dot clock signal DCLK, a data enable signal DES and the like. 
     The gate driver  210  provides a gate signal GS consecutively to a plurality of gate lines GL, based on the gate control signal GDC. The plurality of gate lines GL corresponds to the plurality of pixel areas PA, and each gate line GL connects to pixel areas PA aligned horizontally in parallel among the plurality of pixel areas PA. 
     That is, the gate driver  210  provides a gate signal GS to each gate line GL during each display horizontal period corresponding to each gate line GL of any one frame period included in an image display period. 
     The data driver  220  converts the realigned digital video data RGB′ to an analogue data voltage, based on the data control signal DDC. The data driver  220  provides each data signal Vdata to the data line DL in pixel areas PA to which gate signals GS are provided during each display horizontal period based on the realigned digital video data RGB′. 
     Further, the timing controller  230  may provide a scan control signal for controlling an operation timing of the scan driver  240 , and a read-out control signal for controlling an operation timing of the read-out driver  250 , based on the user&#39;s scanning control input. 
     The scan driver  240  provides a scan signal SS consecutively to a plurality of scan lines SL, based on the scan control signal. That is, the scan driver  240  provides a scan signal SS to each scan line SL during a sensing horizontal period of a sensing period, which corresponds to each scan line SL. 
     The read-out driver  250  reads out each detection signal from pixel areas PA to which a scan signal SS is provided during each sensing horizontal period, through the read-out line ROL, based on the read-out control signal. 
     As illustrated in  FIG.  4   , the light emitting area EA of each pixel area PA corresponds to a light emitting element OLED and a light emitting-driving circuit T 1 , T 2 , T 3 , Cst for driving the light emitting element OLED. 
     In an example, the light emitting-driving circuit may include a first transistor T 1 , a second transistor T 2 , a third transistor T 3 , and a storage capacitor Cst. 
     The first transistor T 1  is disposed between the data line DL and a first node n 1 . 
     The first node n 1  connects to a gate electrode of the second transistor T 2  and one end of the storage capacitor Cst. 
     The first transistor T 1  is turned on based on a gate signal GS provided to the gate line GL, and a data signal Vdata provided to the data line DL is delivered to the first node n 1  through the first transistor T 1  that is turned on. 
     The second transistor T 2  is disposed in series with a light emitting element OLED, between a first driving power source line VDDL supplying a first driving power source EVDD and a second driving power source line VSSL supplying a second driving power source EVSS having a lower electric potential than the first driving power source EVDD. 
     The storage capacitor Cst is disposed between the first node n 1  and the second node n 2 . The second node n 2  is a contact point between the second transistor T 2  and the light emitting element OLED. The storage capacitor Cst may be charged with the data signal Vdata provided to the first node n 1 . 
     The second transistor T 2  is turned on based on the data signal Vdata provided to the first node n 1  and a charging voltage of the storage capacitor Cst, and supplies driving current corresponding to the data signal Vdata to the light emitting element OLED. 
     The third transistor T 3  is disposed between a reference power source line VREL supplying a reference power source Vref for initializing the light emitting element OLED, and the second node n 2 . The third transistor T 3  is turned on based on the gate signal GS provided to the gate line GL, and the electric potential of the second node n 2  is converted to an electric potential the same as the reference power source Vref through the third transistor T 3  that is turned on. 
     As illustrated in  FIG.  5   , the light sensing area SA of each pixel area PA includes a read-out circuit RT for reading out the light sensing element (PD; photo diode), and a detection signal generated by the light sensing element PD. 
     In an example, the read-out circuit may include a read-out transistor RT. 
     The light sensing element PD is disposed between the read-out transistor RT and a bias line BL. The bias line BL is used for supplying a bias power source Vbias to the light sensing element PD. 
     The read-out transistor RT is disposed between the light sensing element PD and the read-out line ROL. 
     When light is incident to the light sensing element PD, the light sensing element PD generates a detection signal corresponding to an amount of the light incident to the light sensing element PD, based on the bias power source Vbias. 
     The read-out transistor RT is turned on based on the scan signal SS provided to the scan line SL, and the detection signal Rdata generated by the light sensing element PD is delivered to the read-out line ROL through the read-out transistor RT that is turned on. 
     For example, the read-out driver ( 250  in  FIG.  3   ) may amplify the detection signal Rdata delivered through the read-out line ROL, and based on the amplified detection signal Rdata, generate a light amount level signal, and combine a light amount level signal corresponding to the light sensing area SA of each pixel area PA and generate a digital image signal. 
     Hereafter, a flat panel in each embodiment is described. 
     A flat panel EM 1  in one embodiment is described with reference to  FIGS.  6  to  12   . 
       FIG.  6    is a view showing a flat panel in  FIGS.  1  and  2   .  FIG.  7    is a view showing a portion of the flat panel in  FIG.  6   .  FIG.  8    is a view showing portion A of  FIG.  7    in one embodiment.  FIG.  9    is a view showing a cross section along I-I′ of  FIG.  8   .  FIG.  10    is a view showing portion B of  FIG.  9   .  FIG.  11    is a view showing portion C of  FIG.  9   .  FIG.  12    is a view showing an example of a light path of each of the adjacent pixel areas among the pixel areas in  FIG.  7   . 
     As illustrated in  FIG.  6   , a flat panel  100  in a first embodiment includes first and second support boards  101 ,  102  that face each other, and a sensing array  110  and a light emitting array  120  that are disposed between the first and second support boards  101 ,  102 . 
     The first and second support boards  101 ,  102  adhere using a predetermined adhesive material (not illustrated) in a state of facing each other. 
     Each of the first and second support boards  101 ,  102  is made of a transparent insulating material. In an example, each of the first and second support boards  101 ,  102  may be made of glass. In another example, each of the first and second support boards  101 ,  102  may be made of a soft transparent insulating material such as plastics and the like. 
     The sensing array  110  includes a plurality of light sensing elements PD corresponding to the light sensing area SA of each of the plurality of pixel areas PA. 
     The light emitting array  120  includes a plurality of light emitting elements OLED corresponding to the light emitting area EA of each of the plurality of pixel areas PA. 
     As illustrated in  FIG.  7   , the flat panel  100  includes a plurality of pixel areas PA that is arranged in a matrix form in the active area in which scanning operation is performed. 
     Each of the plurality of pixel areas PA includes a light emitting area EA that emits light, a light transmitting area TA that is adjacent to the light emitting area EA and transmits light, and a light sensing area SA that constitutes a portion of the light emitting area EA and senses light. 
     In a flat panel  100  that provides the function of displaying a color image, the light emitting area EA of each pixel area PA may emit light corresponding to any one of a plurality of basic colors. The plurality of basic colors may include red, green, blue and white. 
     In an example, the light emitting areas EA 1 , EA 2 , EA 3 , EA 4  of four mutually adjacent pixel areas PA may emit light corresponding to red, green, blue and white, as illustrated in  FIG.  7   . In this case, the four light emitting areas EA 1 , EA 2 , EA 3 , EA 4  that are mutually adjacent and emit light of different basic colors may be determined as a unit pixel UP that displays different colors. 
       FIG.  7    shows the light emitting areas EA of the pixel areas PA, arranged horizontally (the left-right direction in  FIG.  7   ) in parallel with one another, emit light corresponding to the same color, for example. However, as long as a unit pixel UP displaying various colors based on a combination of light corresponding to the plurality of basic colors is implemented, a method by which a basic color is determined for the light emitting areas EA may vary in different ways. 
     As illustrated in  FIG.  8   , the flat panel EM 1  in the first embodiment includes a light emitting element OLED corresponding to the light emitting area EA of each pixel area PA, and a light sensing element PD corresponding to the light sensing area SA of each pixel area PA. 
     The light transmitting area TA of each pixel area PA does not correspond to any one of the light emitting element OLED and the light sensing element PD. Accordingly, the light transmitting area TA transmits larger amounts of light than the light emitting area EA does. Since light passes through the light transmitting area TA, the flat panel  100  may exhibit transparency. 
     That is, since a portion of each of the plurality of pixel areas PA consists of the light transmitting area TA, an object under the flat panel  100  can be recognized by the user, and the user is aware that the flat panel  100  is transparent. 
     Under the assumption that the scanning device  10  generates a digital image signal corresponding to the object to be scanned ( 20  in  FIG.  1   ) under the flat panel  100 , the light sensing element PD of the flat panel  100  may be disposed closer to the object to be scanned  20  than the light emitting element OLED. That is, the light sensing element PD may be disposed under the light emitting element OLED. By doing so, a loss of light reflected from the object to be scanned  20  may decrease in a path to the light sensing element PD. 
     The light emitting-driving circuit T 1 , T 2  for driving the light emitting element OLED corresponds to a portion of the light emitting area EA. 
     Electrode patterns constituting the light emitting-driving circuit T 1 , T 2  may be made of a material that blocks or reflects light, and to minimize a decrease in luminance, caused by the light emitting-driving circuit T 1 , T 2 , the light emitting-driving circuit T 1 , T 2  may be disposed under the light emitting element OLED. That is, the light emitting-driving circuit T 1 , T 2  may be disposed between the light emitting element OLED and the light sensing element PD. 
     As illustrated in  FIG.  5   , both ends of the light sensing element PD connect to the read-out circuit (RT in  FIG.  5   ) and the bias line (BL in  FIG.  5   ). 
     As illustrated in  FIG.  8   , the read-out transistor RT of the read-out circuit, connected to one end of the light sensing element PD corresponds to a portion of the light emitting area EA, and overlaps a portion of the light emitting-driving circuit T 1 , T 2 . 
     The read-out transistor RT may be disposed under the light sensing element PD. 
     Though not illustrated in  FIG.  8   , the bias line BL providing a bias voltage to the light sensing element PD may be arranged to cross the light sensing areas SA of the horizontally or perpendicularly continuous pixel areas PA. 
     The bias line BL may be disposed on/over the light sensing element PD. That is, the bias line BL may be disposed between the light sensing element PD and the light emitting-driving circuit T 1 , T 2 . 
     The flat panel  100  may further include a first light shielding wall SW 1  corresponding to the edge of the light sensing area SA. 
     The flat panel  100  further includes a micro lens (MR in  FIG.  9   ) that is disposed under the light sensing element PD and surrounded by the first light shielding wall SW 1 . 
     The micro lens MR concentrates light reflected from an object to be scanned  20  on the light sensing element PD. With the micro lens MR, a ratio at which the light reflected from the object to be scanned  20  is incident to the light sensing element PD may increase. 
     The first light shielding wall SW 1  blocks light, not reflected from the object to be scanned  20 , from being input to the micro lens MR and the light sensing element PD. With the first light shielding wall SW 1 , the light sensing element PD may generate a detection signal Rdata, based on the light reflected from the object to be scanned  20 . In other words, the effect of light incident from the light emitting element OLED directly to the micro lens MR and the light sensing element PD, light incident to the micro lens MR and the light sensing element PD through the light transmitting area TA, and the like may decrease on the generation of a detection signal Rdata. 
     Thus, with the micro lens MR and the first light shielding wall SW 1 , the accuracy of a detection signal generated by the light sensing element PD may increase. 
     Further, the flat panel  100  includes signal lines GL, SL, DL, ROL arranged around the plurality of pixel areas PA. 
     In an example, the gate line GL and the scan line SL may be disposed horizontally, while the data line DL and the read-out line ROL may be disposed perpendicularly. 
       FIG.  8    shows that the gate line GL and the scan line SL are spaced from each other, and the data line DL and the read-out line ROL are spaced from each other, to intuitively illustrate each component. 
     Unlike the gate line GL and the scan line SL, and the data line DL and the read-out line ROL in  FIG.  8   , the gate line GL and the scan line SL may overlap each other at least partially, and the data line DL and the read-out line ROL may overlap each other at least partially, within the scope in which a signal distortion is prevented. 
     Specifically, the gate lien GL and the data line DL are disposed between the light emitting element OLED and the light sensing element PD, together with the light emitting-driving circuit T 1 , T 2 , and the scan line SL and the read-out line ROL are disposed under the light sensing element PD, together with the read-out transistor RT. 
     As described above, the gate line GL and the scan line SL are disposed in different layers while being disposed in the same direction. Accordingly, the gate line GL and the scan line SL may overlap each other at least partially. Likewise, the data line DL and the read-out line ROL are disposed in different layers while being disposed in the same direction. Accordingly, the data line DL and the read-out line ROL may overlap each other at least partially. This leads to the effective integration of the pixel areas PA, ensuring improvement in resolution. 
     As illustrated in  FIG.  9   , the flat panel EM 1  in the first embodiment includes a first support board  101 , a sensing array  110  disposed on the first support board  101  and including the light sensing element PD corresponding to the light sensing area SA of each of the plurality of pixel areas PA, a micro lens MR disposed between the first support board  101  and the light sensing element PD, a light emitting array  120  disposed on the sensing array  110  and including the light emitting element OLED corresponding to the light emitting area EA of each of the plurality of pixel areas PA, and a second support board  102  disposed on the light emitting array  120  and facing the first support board  101 . 
     If the flat panel EM 1  provides the function of displaying a color image, the flat panel EM 1  may further include a color filter CF that is disposed on one surface of the second support board  102 , faces a fifth protective film  122  and corresponds to the light emitting area EA of each pixel area PA. The color filter CF transmits light rays in a range of wavelengths of the basic colors corresponding to the light emitting area EA of each pixel area PA among light rays of the light emitting element OLED. 
     The sensing array  110  includes a read-out circuit RT disposed on the first support board  101  and corresponding to each of the plurality of pixel areas PA, a first protective film  111  disposed on the first support board  101  and covering the read-out circuit RT, a light sensing element PD disposed on the first protective film  111  and corresponding to the light sensing area SA of each of the plurality of pixel areas PA, a second protective film  112  disposed on the first protective film  11  and covering the light sensing element PD, a bias line BL disposed on the second protective film  112 , and a third protective film  113  disposed on the second protective film  112  and covering the bias line BL. 
     The micro lens MR is concavely disposed on the first protective film  111  and faces a pixel electrode  311 . That is, the pixel electrode  311  is disposed on the first protective film  111  and the micro lens MR and overlaps the micro lens MR. 
     In an example, the micro lens MR may be provided through the processes of patterning the first protective film  111 , disposing a concave part on the first protective film  111  and then filling the concave part of the first protective film  111  with an insulating material. 
     To prevent a loss of light reflected from an object to be scanned  20  on the boundary between the first protective film  111  and the micro lens MR, caused due to total reflection, the micro lens MR is made of a material having a refractive index higher than that of the first protective film  111 . 
     Additionally, to prevent a loss of light reflected from an object to be scanned  20  on the boundary between the first support board  101  and the first protective film  111 , caused due to total reflection, the first protective film  111  is made of a material having a refractive index higher than that of the first support board  101 . 
     The first light shielding wall SW 1  passes through the first protective film  111 . Thus, the lower portion of the first light shielding wall SW 1  may contact the first support board  101 , and the upper portion of the first light shielding wall SW 1  may contact at least a portion of the pixel electrode  311  of the light sensing element PD. 
     Since the micro lens MR is surrounded by the first light shielding wall SW 1 , light incident to the micro lens MR is limited to light that passes through the first support board  101  and the first protective film  111  in the light sensing area SA of each pixel area PA. 
     That is, the first light shielding wall SW 1  may block a path in which light generated in an adjacent pixel area is incident to the micro lens MR through the light transmitting area TA of each pixel area PA. 
     Thus, the accuracy of a detection signal generated by the light sensing element PD may improve. 
     In an example, the first light shielding wall SW 1  may be provided through the processes of forming a hole that passes through the first protective film  111  and then filling the hole of the first protective film  111  with an insulating light shielding material. 
     In another example, the first light shielding wall SW 1  may be provided through the processes of patterning a light shielding material on the first support board  101  in the form of a frame that surrounds the perimeter of the light sensing area SA before disposing the first protective film  111 , disposing the first protective film  111  and then removing the light shielding material that protrudes upward from the first protective film  111 . 
     In yet another example, the first light shielding wall SW 1  may be provided through the processes of patterning a molding material on the first support board  101  in the form of a frame that surrounds the perimeter of the light sensing area SA and removing a portion of a light shielding material disposed on the patterned molding material, which does not cover the molding material. Additionally, the first protective film  111  has a thickness to the extent that the first protective film  111  does not cover the first light shielding wall SW 1 . 
     Since the first light shielding wall SW 1  contacts the pixel electrode  311  of the light sensing element PD, the first light shielding wall SW 1  may be made of an insulating light shielding material. Alternatively, the first light shielding wall SW 1  may be made of an insulating and light absorbing material. 
     As illustrated in  FIG.  10   , the read-out transistor RT of the read-out circuit may include a first active layer  411  disposed on the first support board  101 , a first gate insulating layer  412  disposed on a channel area of the first active layer  411 , a first gate electrode  413  disposed on the first gate insulating layer  412 , a first interlayer insulating film  420  covering the first active layer  411  and the first gate electrode  413 , and a first source electrode  414  and a first drain electrode  415  disposed on the first interlayer insulating film  420 . 
     Referring to  FIG.  5   , the first gate electrode  413  may connect to the scan line SL, the first source electrode  414  may connect to the read-out line ROL, and the first drain electrode  415  may connect to the light sensing element PD. 
       FIG.  10    shows that the read-out transistor RT is a top gate structure, for example. However, the read-out transistor RT can be implemented as a bottom gate structure, a double gate structure and the like. 
     The light sensing element PD includes a pixel electrode  311  and a bias electrode  312  that face each other, and a PIN layer  313  that is disposed between the pixel electrode  311  and the bias electrode  312 . 
     The pixel electrode  311  is disposed on the first protective film  111 . The pixel electrode  311  connects to the read-out transistor RT of the read-out circuit through a first contact hole CT 1  that passes through the first protective film  111 . 
     The pixel electrode  311  overlaps the micro lens MR. Accordingly, light converged by the micro lens MR may be input to the pixel electrode  311 . 
     Additionally, the pixel electrode  311  may overlap at least a portion of the first light shielding wall SW 1  that surrounds the micro lens MR. Alternatively, the first light shielding wall SW 1  may be disposed to surround the edge of the pixel electrode  311 . 
     The PIN layer  313  is disposed on the pixel electrode  311 , and has a structure in which a P-type semiconductor layer, an I-type semiconductor layer and an N -type semiconductor layer are joined. 
     The bias electrode  312  is disposed on the PIN layer  313 . The bias electrode  312  connects to the bias line BL on the second protective film  112  through a bias contact hole that passes through the second protective film  112 . 
     When light is input to the light sensing element PD, an electron-hole pair is generated in the PIN layer  13  having reacted to light, and based on a bias power source Vbias supplied to the bias electrode  312 , the electron of the electron-hole pair moves. Thus, a detection signal Rdata corresponding to an amount of the light incident to the light sensing element PD is generated. 
     Referring back to  FIG.  9   , the light emitting array  120  is disposed on the third protective film  113  of the sensing array  110 . 
     The light emitting array  120  includes light emitting-driving circuits T 1 , T 2  disposed on the third protective film  113  and corresponding to each of the plurality of pixel areas PA, a fourth protective film  121  disposed on the third protective film  113  and covering the light emitting-driving circuit T 1 , T 2 , a light emitting element (OLED) disposed on the fourth protective film  121  and corresponding to the light emitting area EA of each of the plurality of pixel areas PA, and a fifth protective film  122  disposed on the fourth protective film  121  and covering the light emitting element OLED. 
     As illustrated in  FIG.  11   , the first transistor T 1  of the light emitting-driving circuits T 1 , T 2  may include a second active layer  431  disposed on the third protective film  113 , a second gate insulating layer  432  disposed on the channel area of the second active layer  431 , a second gate electrode  433  disposed on the second gate insulating layer  432 , a second interlayer insulating film  440  covering the second active layer  431  and the second gate electrode  433 , and a second source electrode  434  and a second drain electrode  435  disposed on the second interlayer insulating film  440 . 
     Likewise, the second transistor T 2  may include a third active layer  451  disposed on the third protective film  113 , a third gate insulating layer  452  disposed on the channel area of the third active layer  451 , a third gate electrode  453  disposed on the third gate insulating layer  452 , a second interlayer insulating film  440  covering the first active layer  451  and the third gate electrode  453 , and a third source electrode  454  and a third drain electrode  455  disposed on the second interlayer insulating film  440 . 
     Referring to  FIG.  4   , the second gate electrode  433  of the first transistor T 1  may connect to the gate line GL, the second source electrode  434  may connect to the data line DL, and the second drain electrode  435  may connect to the third gate electrode  452  of the second transistor T 2 . 
     Additionally, the third source electrode  454  of the second transistor T 2  may connect to the first driving power source line VDDL, and the third drain electrode  455  may connect to the light emitting element OLED, for example. 
     However, depending on the structure of the element, the connection point of the source electrode may be exchanged with the connection point of the drain electrode. 
       FIG.  11    shows that the first and second transistors T 1 , T 2  are a top gate structure, for example. Certainly, the first and second transistors T 1 , T 2  may also be implemented as a bottom gate structure, a double gate structure, and the like. 
     Hereafter,  FIG.  9    is described again. 
     The light emitting element OLED includes a first electrode  321  and a second electrode  322  that face each other, and a light emitting layer  323  that is disposed between the first electrode  321  and second electrode  322 . 
     The first electrode  321  is disposed on the fourth protective film  121  and corresponds to the light emitting area EA of each of the plurality of pixel areas PA. The first electrode  321  connects to the second transistor T 2  of the light emitting-driving circuit through a second contact hole CT 2  that passes through the fourth protective film  121 . 
     Since the first electrode  321  corresponds to the light emitting area EA, a portion of the first electrode  321 , corresponding to a main light emitting area MEA, is disposed on a light shielding-reflecting layer LSL, and the remaining portion is disposed on the fourth protective film  121 . 
     The light emitting layer  323  is disposed on the fourth protective film  121  and covers a plurality of first electrodes  321  corresponding to the plurality of pixel areas PA. 
     Though not illustrated in  FIG.  9   , in a light emitting array  120  that further includes a bank (not illustrated) disposed on the fourth protective film  121  and covering the edge of the first electrode  321 , the light emitting layer  323  further covers the bank (not illustrated). 
     The second electrode  322  is disposed on the light emitting layer  323  and corresponds to the plurality of pixel areas PA. 
     In an example, the light emitting layer  323  and the second electrode  322  may be formed in a single pattern. 
     The first and second electrodes  321 ,  322  may be made of a transparent conductive material or a semitransparent conductive material respectively. 
     Accordingly, the light emitting layer  323 &#39;s light may be emitted to both sides through the first and second electrodes  321 ,  322 . 
     However, the light emitting element OLED&#39;s light needs to be emitted to the first support board  101  to perform the scanning operation as well as the second support board  102  to display an image. 
     To this end, in one embodiment, the light emitting array  120  further includes a light shielding-reflecting layer disposed below the light emitting element OLED and corresponding to a portion of the light emitting area EA. 
     The light shielding-reflecting layer LSL is disposed between the fourth protective film  121  and the light emitting element OLED, i.e., between the fourth protective film  121  and the first electrode  321 , and corresponds to the main light emitting area MEA that is a portion of the light emitting area EA. 
     The light shielding-reflecting layer LSL reflects the light emitting element OLED&#39;s light to the second support board  102  and blocks the light emitting element OLED&#39;s light from moving to the first support board  101 . 
     Since the light emitting array  120  includes the light shielding-reflecting layer LSL as described above, the light emitting area EA of each pixel area PA includes a main light emitting area MEA that emits light to one side, i.e., toward the second support board  102 , and a sub light emitting area SEA that emits light to both sides, i.e., toward the first support board  101  and the second support board  102 . 
     Additionally, the light shielding-reflecting layer LSL overlaps the read-out circuit RT, the light sensing element PD, and the light emitting-driving circuits T 1 , T 2 . That is, the read-out circuit RT, the light sensing element PD, and the light emitting-driving circuits T 1 , T 2  are disposed in the main light emitting area MEA corresponding to the light shielding-reflecting layer LSL. 
     Thus, the read-out circuit RT, the light sensing element PD, and the light emitting-driving circuits T 1 , T 2  are not recognized by the user facing the second support board  102 , thereby preventing deterioration in display quality. 
     Further, since the light shielding-reflecting layer LSL is disposed between the light sensing element PD and the light emitting element OLED, the light emitting element OLED&#39;s light is not directly input to the bias electrode  312  of the light sensing element PD. 
     As illustrated in  FIG.  12   , the light emitting element OLED&#39;s light corresponding to the light emitting area EA is emitted to one side, i.e., toward the second support board  102 , in the main light emitting area MEA corresponding to the light shielding-reflecting layer LSL. Additionally, the light emitting element OLED&#39;s light corresponding to the light emitting area EA is emitted to both sides, i.e., toward the first support board  101  and the second support board  102 , through the first and second electrodes  321 ,  322 , in the sub light emitting area SEA in which the light shielding-reflecting layer LSL is not disposed. 
     A portion of the light emitting element OLED&#39;s light, emitted toward the first support board  101 , is reflected from an object to be scanned  20  disposed below the first support board  101 . 
     In this case, the fourth protective film  121 , the third protective film  113 , and the second protective film  112  and the first protective film  111  are made of a material that has a higher refractive index in the order of the fourth protective film  121 , the third protective film  113 , and the second protective film  112  and the first protective film  111 , such that a portion of the light emitting element OLED&#39;s light, emitted toward the first support board  101 , is prevented from being lost due to total reflection on the boundaries among the fourth protective film  121 , the third protective film  113 , and the second protective film  112  and the first protective film  111  until the portion reaches an object to be scanned  20 . 
     That is, the third protective film  113  has a higher refractive index than the fourth protective film  121 , the second protective film  112  has a higher refractive index than the third protective film  113 , and the first protective film  111  has a higher refractive index than the second protective film  112 . 
     The light sensing element PD generates a detection signal Rdata corresponding to an amount of light reflected from the object to be scanned  20  and input through the micro lens MR. 
     The micro lens MR converges the light reflected from the object to be scanned  20  and delivers the converged light to the light sensing element PD, resulting an increase in the amount of the light input to the light sensing element PD. 
     Because of the first light shielding wall SW 1  of each pixel area PA, light incident to the micro lens MR of each pixel area PA may correspond to the light sensing area SA of each pixel area PA and be limited to light reflected from an object to be scanned  20 . 
     Additionally, the light shielding-reflecting layer LSL disposed between the light sensing element PD and the light emitting element OLED may prevent the light emitting element OLED&#39;s light from being input to the light sensing element PD through the bias electrode  312  of the light sensing element PD. 
     Since the flat panel EM 1  in the first embodiment includes the light shielding-reflecting layer LSL, the micro lens MR and the first light shielding wall SW 1  as described above, the accuracy of a detection signal Rdata generated in the light sensing element PD may improve. Thus, consistency between a digital image signal generated by the scanning device  100  and an object to be scanned  20  may improve. 
     As illustrated in  FIG.  12   , a portion of light generated in any one pixel area PA 1  may be input to the light sensing element PD of an adjacent pixel area PA 2  through the light transmitting area TA of each pixel area PA 1 , PA 2 . Thus, improvement in the accuracy of a detection signal Rdata generated by the light sensing element PD is limited. 
     To solve the problem, a second embodiment is provided. 
       FIG.  13    is a view showing portion A of  FIG.  7    in a second embodiment.  FIG.  14    is a view showing a cross section along II-II′ of  FIG.  13   .  FIGS.  15  to  18    are views showing an example of a flat surface shape of single layer patterns included in a second light shielding wall in  FIG.  14   .  FIG.  19    is a view showing an example of light paths of any two adjacent pixel areas of a flat panel in the second embodiment. 
     As illustrated in  FIG.  13   , the flat panel EM 2  in the second embodiment is the same as that EM 1  in the first embodiment except that the flat panel EM 2  in the second embodiment further includes a second light shielding wall SW 2  surrounding the light emitting area EA of each of the plurality of pixel areas PA. Hereafter, a repetition of description is avoided. 
     As illustrated in  FIG.  14   , the second light shielding wall SW 2  is disposed on the first support board  101 , and passes through the first protective film  111 , the second protective film  112 , the third protective film  113  and the fourth protective film  121  respectively. 
     The second light shielding wall SW 2  consists of single-layer patterns (SW 21 , SW 22 , SW 23 , SW 24 ) that passes through the first protective film  111 , the second protective film  112 , the third protective film  113  and the fourth protective film  121  respectively and overlaps one another. 
     As illustrated in  FIG.  13   , the second light shielding wall SW 2  consisting of the single-layer patterns SW 21 , SW 22 , SW 23 , SW 24  overlapping one another has a closed shape. 
     However, at least one of the single-layer patterns SW 21 , SW 22 , SW 23 , SW 24  may have an open shape in which at least one of the single-layer patterns SW 21 , SW 22 , SW 23 , SW 24  is spaced from a signal line. 
     In an example, as illustrated in  FIGS.  14  and  15   , the scan line SL, the read-out line ROL and the read-out circuit RT are disposed on the first support board  101 . Since a first single-layer pattern SW 21  on the first support board  101  is disposed in a way that passes through the first protective film  111  on the first support board  101 , the first single-layer pattern SW 21  crosses the connection portion among the scan line SL, each of the read-out lines ROL, and the read-out circuit RT. 
     In this case, since a portion of the first single-layer pattern SW 21 , crossing the connection portion among the scan line SL, each of the read-out lines ROL, and the read-out circuit RT, is removed, the first single-layer pattern SW 21  has an open shape. 
     As illustrated in  FIGS.  14  and  16   , the light sensing element PD corresponding to the light sensing area SA of each pixel area PA is disposed on the first protective film  111 . That is, a signal wire is not disposed on the first protective film  111 . 
     A second single-layer pattern SW 22  on the first protective film  111  is disposed in a way that passes through the second protective film  112  on the first protective film  111 . Since the second single-layer pattern SW 22  includes no portion in which the second single-layer pattern SW 22  crosses a signal line disposed on the same layer, the second single-layer pattern SW 22  has a closed shape. 
     As illustrated in FGIS.  14  and  17 , the bias line BL is disposed on the second protective film  112  covering the light sensing element PD. A third single-layer pattern SW 23  on the second protective film  112  is disposed in a way that passes through the third protective film  113  on the second protective film  112 , and crosses the bias line BL. 
     In this case, since a portion of the third single-layer pattern SW 23 , crossing the bias line BL, is removed, and the third signal-layer pattern SW 23  has an open shape. 
     As illustrated in  FIGS.  14  and  18   , the light emitting-driving circuits T 1 , T 2 , the gate line GL and the data line DL are disposed on the third protective film  113  covering the bias line BL. A fourth single-layer pattern SW 24  on the third protective film  113  is disposed in a way that passes through the fourth protective film  121  on the third protective film  113 , and crosses the connection portion between each of the gate line GL and the data line DL and the light emitting-driving circuit T 1 , T 2 . 
     Thus, a portion of the fourth single-layer pattern SW 24 , crossing the connection portion between each of the gate line GL and the data line DL and the light emitting-driving circuit T 1 , T 2 , is removed, and the fourth single-layer pattern SW 24  has an open shape. 
     The second light shielding wall SW 2  in which the first, second, third and fourth single-layer patterns SW 21 , SW 22 , SW 23 , SW 24  overlap one another may be insulated from the read-out circuit RT, the scan line SL, the read-out line ROL, the bias line BL, the light emitting-driving circuit T 1 , T, the gate line GL and the data line DL respectively. Thus, signal distortion or short caused by the second light shielding wall SW 2  may be prevented. 
     The second light shielding wall SW 2  blocks a path in which an adjacent pixel area PA&#39;s light is incident to the light sensing element PD. 
     That is, as illustrated in  FIG.  19   , the second light shielding wall SW 2 , surrounding the light emitting area EA of each pixel area PA, may block the delivery of light through the light transmitting area TA of each pixel area PA. 
     This means that even if light generated in any one pixel area PA 1  is emitted toward an adjacent pixel area PA 2  through at least one of the first transparent support board  101 , the first protective film  111 , the second protective film  112 , the third protective film  113  and the fourth protective film  121 , the light may be blocked by the second light shielding wall SW 2 . 
     Accordingly, the light sensing element PD of each pixel area PA 2  may generate a detection signal Rdata in a state in which the light sensing element PD is not affected by light generated in an adjacent pixel area PA 1 . As a result, the accuracy of a detection signal Rdata generated in the light sensing element PD may improve further, and consistency between a digital image signal generated by the scanning device  100  and an object to be scanned  20  may improve further. 
     Further, since the sensing array  110  and the light emitting array  120  overlap each other, signal interference may occur. To prevent this from happening, a third embodiment is provided. 
       FIG.  20    is a view showing a cross section along II-II′ of  FIG.  13    in a third embodiment. 
     As illustrated in  FIG.  20   , a flat panel EM 3  in a third embodiment is the same as those in the first and second embodiments except that the flat panel EM 3  in the third embodiment further includes an electromagnetic shielding pattern  130  disposed between the sensing array  110  and the light emitting array  120 , and a secondary protective film  131  covering the electromagnetic shielding pattern  130  and that the light emitting array  120  is disposed on the secondary protective film  131 . Hereafter, a repetition of description is avoided. 
     The electromagnetic shielding pattern  130  is disposed on the third protective film  113  that is the uppermost portion of the sensing array  110  and covers the bias line BL. 
     The electromagnetic shielding pattern  130  is to block signal interference among the read-out circuit RT, the light sensing element PD, and the light emitting-driving circuit T 1 , T 2  that overlap one another in the main light emitting area MEA. The electromagnetic pattern  130  corresponds to the main light emitting area MEA together with the read-out circuit RT, the light sensing element PD and the light emitting-driving circuit T 1 , T 2 . Accordingly, the electromagnetic shielding pattern  130  overlaps the light shielding-reflecting layer LSL corresponding to the main light emitting area MEA. 
     The secondary protective film  131  is disposed on the third protective film  113  and covers the electromagnetic shielding pattern  130 . 
     The light emitting array  120  is disposed on the secondary protective film  131 . 
     Additionally, the second light shielding wall SW 2  may be implemented as a structure in which a signal-layer pattern passing through the secondary protective film  131  is further included. 
     As described above, the flat panel EM 1 , EM 2 , EM 3  in each of the embodiments includes the micro lens MR corresponding to the light sensing area SA of each pixel area PA, the first light shielding wall SW 1  corresponding to the edge of the light sensing area SA of each pixel area PA, and the light shielding-reflecting layer LSL corresponding to the main light emitting area MEA of each pixel area PA and disposed under of the light emitting element OLED. 
     With the micro lens MR, the first light shielding wall SW 1  and the light shielding-reflecting layer LSL, light delivered to the light sensing element PD of each pixel area PA is limited to light emitted from the light emitting element of each pixel area PA, reflected from an object to be scanned  20  disposed under the first support board  101  and converged by the micro lens MR. Thus, the accuracy of a detection signal Rdata generated by the light sensing element PD may improve. 
     That is, since the flat panel EM 1  in the first embodiment includes the plurality of pixel areas PA including the light transmitting area TA respectively, the flat panel EM 1  may look transparent and ensure improvement in the accuracy of a detection signal Rdata generated by the light sensing element PD. 
     Additionally, the flat panel EM 2  in the second embodiment further includes the second light shielding wall SW 2  that surrounds the light emitting area EA of each pixel area PA. The second light shielding wall SW 2  may block a light path between adjacent pixel areas PA. That is, the light sensing element PD of each pixel area PA may not be exposed to light generated in an adjacent pixel area. Thus, the accuracy of a detection signal Rdata generated by the light sensing element PD may improve further. 
     Further, the flat panel EM 3  in the third embodiment further includes the electromagnetic shielding pattern  130  disposed between the sensing array  110  and the light emitting array  120 . Accordingly, signal interference between the sensing array  110  and the light emitting array  120  may be blocked, resulting in a decrease in the distortion of a driving signal provided to the light emitting area EA of each pixel area PA and the distortion of a detection signal Rdata read out in the light sensing element PD of each pixel area PA. 
     The subject matter of the disclosure is not limited by the embodiments and drawings set forth herein, and replacements, modifications and changes can be made by one having ordinary skill in the art without departing from the technical spirit of the disclosure.