Patent Publication Number: US-7595590-B2

Title: Plasma display apparatus

Description:
CLAIM OF PRIORITY 
   This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. § 119 from an application for PLASMA DISPLAY APPARATUS earlier filed in the Korean Intellectual Property Office on 4 Apr. 2005 and there duly assigned Serial No. 10-2005-0028085. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a plasma display apparatus, and more particularly, to a plasma display panel for displaying an image so that a user can think that he/she is watching a screen larger than it really is. 
   2. Description of the Related Art 
   Plasma display apparatuses are flat panel displays displaying an image using a gas discharge, and are considered to be the next generation of flat panel displays due to high display properties such as display capacity, brightness, contrast, image sticking, and viewing angle. 
   In general, the plasma display apparatus includes a plasma display panel, a chassis substantially parallel to the plasma display panel, a circuit unit disposed on a rear portion of the chassis to drive the plasma display panel, and a case accommodating the plasma display panel, the chassis, and the circuit unit. 
   However, since size of the plasma display apparatus increases, the price of the apparatus greatly increases, and thus, consumers may not afford to buy the apparatus of desired size. When the size of the plasma display apparatus increases, the fabrication costs increase more. 
   Therefore, the plasma display apparatus, fabrication costs of which less increases, and by which a user can feel enlarged screen, is required. 
   SUMMARY OF THE INVENTION 
   The present invention provides a plasma display apparatus having an auxiliary display member which causes a user to think that he/she is seeing a screen that appears larger than it really is. 
   According to one aspect of the present invention, a plasma display apparatus is provided including: a plasma display panel including a display area adapted to display an image; and an auxiliary display member surrounding the display area of the plasma display panel. 
   The auxiliary display member is preferably adapted to display an image using a plurality of Light Emitting Diodes (LEDs). The auxiliary display member is preferably adapted to display an image corresponding to the image displayed on an edge of the display area. The auxiliary display member preferably includes unit pixels adapted to display an average of images displayed by a predetermined number of pixels disposed along an edge of the display area. 
   According to another aspect of the present invention, a plasma display apparatus is provided including: a plasma display panel including a display area adapted to display an image; an auxiliary display member surrounding the display area of the plasma display panel; and a chassis including a front surface attached to the plasma display panel and a rear surface including a circuit unit having circuits adapted to drive the plasma display panel contained therein. 
   The apparatus preferably further includes a front case including a window adapted to enable the image displayed on the display area to be viewed and a rear case attached to the front case to define an inner space containing the plasma display panel. 
   The auxiliary display member is preferably disposed between the front case and the plasma display panel. 
   The auxiliary display member is preferably adapted to display an image using a plurality of Light Emitting Diodes (LEDs). The auxiliary display member is preferably adapted to display an image corresponding to the image displayed on an edge of the display area. The auxiliary display member preferably includes unit pixels adapted to display an average of images displayed by a predetermined number of pixels disposed along an edge of the display area. 
   A portion of the front case corresponding to the auxiliary display member preferably includes a translucent material. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the present invention and many of the attendant advantages thereof, will be readily apparent as the present invention becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein: 
       FIG. 1  is an exploded perspective view of a plasma display apparatus according to an embodiment of the present invention; 
       FIG. 2  is a cross-sectional view of the plasma display apparatus taken along line II-II of  FIG. 1 ; 
       FIG. 3  is a plan view of pixels in the plasma display panel of  FIG. 1  and pixels of an auxiliary display member; 
       FIG. 4  is a partial exploded perspective view of an example of the plasma display panel of  FIG. 1 ; and 
       FIG. 5  is a block diagram illustrating operations of a circuit unit of  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  is an exploded perspective view of a plasma display apparatus  100  according to an embodiment of the present invention, and  FIG. 2  is a cross-sectional view of the plasma display apparatus  100  taken along line II-II of  FIG. 1 . Referring to the drawings, the plasma display apparatus  100  includes a front case  180 , a rear case  185 , a plasma display panel  10 , a chassis  140 , a circuit unit  150 , and an auxiliary display member  190 . 
   The front case  180  includes a window  186 , to which an image realized by the plasma display panel  110  is projected, formed on a center portion thereof and surrounded by a peripheral portion  182 . The rear case  185  is attached to the front case  180  to define a space  115 , in which the plasma display panel  110 , the chassis  140 , and the circuit unit  150  are disposed. 
   A filter  177  is disposed on a rear portion of the front case  180  to cover the window  186 . In addition, the filter  177  shields electromagnetic waves generated by the plasma display panel  110  and the circuit unit  150 , and protects the plasma display panel  110 . It is preferable for the filter  177  to be formed of a material including a glass. The filter  177  is attached to the peripheral portion  182  of the front case  180  by a filter holder  175 . That is, coupling bosses  183  are formed on the peripheral portion  182  of the front case  180 , and the coupling bosses  183  are coupled to screws  187  inserted into penetration holes  175   a  of the filter holder  175 . The filter  177  is disposed between the filter holder  175  and the front case  180 , and thus, the filter  177  is fixedly pressed onto the peripheral portion  182  of the front case  180  by the above coupling structure. 
   In addition, a buffer member  188  is disposed between the plasma display panel  110  and the filter holder  175  to prevent the plasma display panel  110  from being damaged due to direct contact with the filter holder  175 . 
   The plasma display panel  110  is disposed on a rear portion of the filter holder  175 , and the plasma display panel  110  displays an image using a gas discharge.  FIG. 3  is a plan view of arrangements of pixels in the plasma display panel  110  and pixels in the auxiliary display member  190  shown in  FIG. 1 . Referring to  FIG. 3 , the plasma display panel  110  includes a display area  113  disposed on a center portion of the panel  110  and displaying a substantial image, and a non-display area  114  surrounding the display area  113  and including terminal portions (not shown). The image generated on the display area  113  of the plasma display panel  110  exits through the window  186  of the front case  180 , and the display area  113  includes a plurality of pixels P 11 , P 12 , . . . , Pmn. In addition, each of the pixels P 11 , P 12 , . . . , Pmn includes a red sub-pixel (R), a green sub-pixel (G), and a blue sub-pixel (B). For example, the pixel P 11  includes the red sub-pixel R 11 , the green sub-pixel G 11 , and the blue sub-pixel B 11 , and the pixel Pmn includes the red sub-pixel Rmn, the green sub-pixel Gmn, and the blue sub-pixel Bmn. 
   Various kinds of plasma display panels can be used as the plasma display panel  110 , for example, an Alternating Current (AC) plasma display panel having a surface-discharge three-electrode structure can be used as shown in  FIG. 4 . 
   Referring to  FIG. 4 , the plasma display panel  110  includes a front panel  120 , and a rear panel  130  coupled to the front panel  120 . The front panel  120  includes a front substrate  121 , sustain electrode pairs  122  formed on a rear surface of the front substrate  121 , each of the pairs including an X electrode  123  and a Y electrode  124 , a front dielectric layer  125  covering the sustain electrode pairs  122 , and a protective layer  126  formed on a rear surface of the front dielectric layer  125 . The X electrode  123  and the Y electrode  124  perform as a common electrode and a scan electrode respectively, and are separated from each other by a discharge gap. In addition, the X electrode  123  includes an X transparent electrode  123   a  and an X bus electrode  123   b  connected to the X transparent electrode  123   a , and the Y electrode  124  includes a Y transparent electrode  124   a  and a Y bus electrode  124   b  connected to the Y transparent electrode  124   a.    
   The rear panel  130  includes a rear substrate  131 , address electrodes  132  formed on a front surface of the rear substrate  131  and extending in a direction of crossing the sustain electrode pairs  122 , a rear dielectric layer  133  covering the address electrodes  132 , barrier ribs  134  formed on the rear dielectric layer  133  to define red, green, and blue discharge cells  135 R,  135 G, and  135 B, phosphor layers  136 R,  136 G, and  136 B disposed in the discharge cells  135 R,  135 G, and  135 B, and a discharge gas filled in the discharge cells  135 R,  135 G, and  135 B. The red discharge cell  135 R corresponds to the red sub-pixel Ra and includes the red phosphor layer  136 R, the green discharge cell  135 G corresponds to the green sub-pixel Gb and includes the green phosphor layer  136 G, and the blue discharge cell  135 B corresponds to the blue sub-pixel Bc and includes the blue phosphor layer  136 B. 
   Referring to  FIGS. 1 through 3 , the auxiliary display member  190  is disposed between the front case  180  and the filter holder  175 . The auxiliary display member  190  is fixed on a rear surface of the front case  180 , and surrounds the window  186  of the front case  180 . Therefore, the auxiliary display member  190  surrounds the display area  113  of the plasma display panel  110 , and displays an image surrounding the display area  113 . It is preferable for a portion  181  of the front case  180  where the auxiliary display member  190  is disposed to be formed of a translucent material, and thus, the image generated by the auxiliary display member  190  can be projected frontward. In addition, since the auxiliary display member  190  is visible to the user when the portion  181  of the front case  180  is formed of the transparent material, degradation of appearance can be prevented when the auxiliary display member  190  is formed of the translucent material. Various image display apparatuses can be used in the auxiliary display member  190 , Preferably, Light Emitting Diodes (LEDs)  194  can be used in the auxiliary display member  190 . In the present embodiment, the auxiliary display member  190  includes a plurality of pixels, and each of the pixels includes red, green, and blue LEDs  194 . In addition, the pixels of the auxiliary display member  190  are arranged in an order of a first pixel Q 1  , a second pixel Q 2 , . . . , a Lth pixel QL from upper left portion of the display area  113  in a clockwise direction. 
   The chassis  140  that can be formed using a casting or a pressing process. The chassis  140  supports the plasma display panel  110  and the circuit unit  150 . The chassis  140  can be formed of a metal having a high thermal conductivity, such as aluminum, in order to dissipate the heat transmitted from the plasma display panel  110 . The plasma display panel  110  and the chassis  140  are attached to each other using a dual-adhesive tape  141 . 
   A thermal conductive sheet  142  is disposed between the plasma display panel  110  and the chassis  140  to diffuse the heat generated locally on the plasma display panel  110  and transmit some of the heat generated from the plasma display panel  110  to the chassis  140 . The thermal conductive sheet  142  can be a silicon glass, a silicon heat dissipation sheet, an acryl-based heat dissipation and pressure reduction adhesive sheet, a urethane-based heat dissipation and pressure reduction adhesive sheet, or a carbon sheet. 
   The circuit unit  150  is disposed on a rear portion of the chassis  140 , and the circuit unit  150  includes a plurality of circuit wires and a plurality of various electronic elements connected to the circuit wires. The circuit unit  150  drives the plasma display panel  110 . Referring to  FIG. 5 , the circuit unit  150  includes an image processor  151 , a logic controller  152 , an address driver  153 , an X driver  154 , a Y driver  155 , an auxiliary display driver  158 , and a power supplier  156 . The image processor  151  converts an external analog image signal into a digital signal to generate internal image signals, for example, red, green, and blue image data, a clock signal, and vertical and horizontal synchronization signals of 8 bits, respectively. 
   The logic controller  152  generate driving control signals SA, SY, and SX for the plasma display panel  110  according to the internal image signals from the image processor  151 . In addition, the logic controller  152  includes a calculation unit (not shown) and a memory (not shown) for generating driving control signals for the auxiliary display driver  158 . That is, the logic controller  152  calculates the driving control signals S A , S Y , and S X  for the plasma display panel  110  into the signals for displaying image of the auxiliary display panel  190  using the calculation unit, and stores the driving control signals S A , S Y , and S X  and/or the calculated driving control signals in the memory. In addition, the logic controller  152  outputs the calculated driving control signals to the auxiliary display driver  158 . 
   The address driver  153  processes the address signal S A  among the driving control signals S A , S Y , and S X  to generate a display data signal, and applies the display data signal to the address electrodes  132 . The X driver  154  processes the X driving control signal S X  among the driving control signals S A , S Y , and S X  from the logic controller  152 , and applies the processed signals to the X electrodes  123 . The Y driver  155  processes the Y driving control signal S Y  among the driving control signals S A , S Y , and S X  from the logic controller  152 , and applies the processed signal to the Y electrodes  124 . 
   The auxiliary display driver  158  receives the driving signals output from the logic controller  152  and drives the red, green, and blue LEDs  194 . 
   In addition, the power supplier  156  generates and supplies operational voltages required by the image processor  151  and the logic controller  152 , and operational voltages required by the address driver  153 , the X driver  154 , the Y driver  155 , and the auxiliary display driver  158 . 
   The circuit unit  150  transmits electrical signals to the plasma display panel  110  via signal transmission units. The signal transmission units can be selected from Flexible Printed Cable (Fpc), Tape Carrier Package (TCP), and Chip on Film (COF). According to the present embodiment, FPCs  160  are disposed on left and right sides of the chassis  140  as the signal transmission units, and TCPs  170 , each of which is formed by mounting at least one electronic device on a tape wiring unit, are disposed on upper and lower portions of the chassis  140  as the signal transmission units. In addition, referring to  FIG. 1 , the TCPs  170  are spaced apart from each other on upper and lower sides of the chassis  140 . 
   Referring to  FIG. 3 , images displayed by the plasma display panel  110  and the auxiliary display member  190  are described in detail as follows. 
   As described above, the plasma display panel  110  displays the image using the gas discharge, and the plurality of pixels arranged in the display area  113  realize the image according to the signals of the logic controller  152 . In addition, the auxiliary display member  190  surrounding the display area  113  of the plasma display panel  110  displays the image realized by the pixels disposed on the edge of the plasma display panel  110 . 
   That is, the plurality of pixels are arranged along the edge of the display area  113  of the plasma display panel  110 . The pixels P 11 , P 12 , . . . , P 1 n, P 2 n, . . . , Pmn, . . . Pm(n−1), . . . , Pm 1 , . . . , P 21  are arranged from the upper left portion of the display area  113  in a clockwise direction. Each of the pixels includes the red, green, and blue sub-pixels. 
   In addition, as described above, the first pixel Q 1 , the second pixel Q 2 , . . . , the Lth pixel QL of the auxiliary display member  190  are disposed along the edge of the display area  113 . In the present embodiment, the unit pixel of the auxiliary display member  190  corresponds to three pixels of the plasma display panel  10 , and preferably, is disposed to correspond to adjacent pixels of the plasma display panel  110 . Referring to  FIG. 3 , the first pixel Q 1  of the auxiliary display member  190  corresponds to the pixels P 11 , P 12 , and P 13  of the plasma display panel  110 . The pixels of the auxiliary display member  190  arranged on left and right edges and lower edge of the display area  113  also correspond to the pixels of the plasma display panel  110  in one-to-three correspondences. 
   The pixels of the plasma display panel  110  and the corresponding pixel of the auxiliary display member  190  relate to each other to display image. For example, the unit pixel of the auxiliary display member  190  displays the image having an average color and an average saturation of the relating three pixels of the plasma display panel  110 . Therefore, the auxiliary display member  190  can display the image similar to that of the pixels disposed on the edges of the plasma display panel  10 . According to the present embodiment, three pixels of the plasma display panel  110  correspond to one pixel of the auxiliary display member  190 . However, the present invention is not limited thereto. 
   As described above, when the image of the plasma display panel  110  is supported by the auxiliary display member  190 , the user can see the extended image displayed by the auxiliary display member  190 , as well as the image displayed on the display area  113  of the plasma display panel  110 , and thus, the user can feel that he/she is viewing a larger screen. In particular, since the viewing angle of human being is concentrated on the center of the screen, less information can be displayed on the edge of the screen. Therefore, when the color, not detailed information of the image, is displayed on the outer portion of the screen, the user can see the clear image of high quality, and at the same time, can think that he/she sees the screen larger than it really is. In addition, according to the present embodiment, the auxiliary display member  190  displays the image using the LEDs. However, small bulbs or fluorescent lamps can be used to display the auxiliary image. 
   According to the present invention, the image area of the plasma display panel can be expanded by the auxiliary display member. Therefore, the user can think that he/she sees the screen larger than it really is. 
   While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various modifications in form and detail can be made therein without departing from the spirit and scope of the present invention as defined by the following claims.