Patent Publication Number: US-6218784-B1

Title: Plasma display panel apparatus having a driving circuit unit thereon

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a PDP(Plasma Display Panel) apparatus, and in particular to a PDP apparatus combined a PCB(Printed Circuit Board) substrate on which formed driving circuits and panel unit into a single body. The panel unit includes two flat type substrates facing each other and a plurality of discharge cells disposed between the two flat type substrates. 
     2. Description of the Background Art 
     Recently, a flat panel display such as a LCD(Liquid crystal display), a FED(Field emission display), a PDP(Plasma Display Panel), etc. is intensively studied. Among the above-described units, the PDP is a display apparatus and attracts a big attention based on its advantage such as an easier fabrication due to its simple structure, a high luminance and high light emitting efficiency, a good memory function, and a wider view angle above 160 for thereby implementing a large size screen above 40 inches. 
     The PDP apparatus includes a panel unit formed of a plurality of discharge cells, and a driving circuit unit for supplying a power or signal to the panel unit. 
     The panel unit is formed of a pair of glass base plates, and a plurality of discharge cells disposed therebetween. 
     The driving circuit for driving the panel unit is installed on a PCB(Printed Circuit Board) substrate. In addition, the discharge cells of the panel unit and the driving circuit formed on the PCB substrate are connected by a certain known method. 
     FIG. 1 is an exploded respective view illustrating a panel unit of a conventional PDP apparatus. 
     As shown therein, the panel unit of the conventional PDP apparatus includes two glass substrates  10  and  20 , and a plurality of discharge cells  30  formed therebetween. Among two glass substrates  10  and  20 , the glass substrate  10  is a front substrate  10  for displaying a certain character or image, and the other glass substrate  20  is a rear substrate  20 . 
     A plurality of address electrodes  21  are parallely formed at a certain distance on the upper surface of the rear substrate  20  formed of a glass material, a dielectric layer  22  is formed on the upper surfaces of the address electrodes  21  and the rear substrate  20 , and a barrier  23  is formed between each neighboring address electrodes  21  for separating the discharge cells  30 . A fluorescent substance layer  24  is formed at a lateral wall of the barrier  23  of each discharge cell  30  and on the upper surface of the dielectric layer  22 . 
     A pair of sustain electrodes  11  are formed in parallel on the lower surface of the front substrate  10  which is another glass substrate, and a dielectric layer  12  is formed on the lower surfaces of the sustain electrodes  11  and the front substrate  10 , and a dielectric layer protection film  13  is formed on the surfaces of the dielectric layer  12 . 
     The panel unit of the PDP is formed by bonding the front substrate  10  and the rear substrate  20 . 
     However, the apparatus for displaying a certain character or image is not implemented by the above-described panel unit. Namely, a PDP driving circuit unit is used for applying a certain voltage and signal to the panel unit. In addition, the PDP driving circuit unit is generally a PCB(Printed Circuit Board) substrate which is formed by disposing a plurality of driving circuit integration devices on a substrate having printed wires thereon for driving the panel unit. In addition, the electrodes of the panel units and the circuit of the driving circuit unit are electrically connected for thereby implementing a PDP apparatus. 
     The conventional method for electrically connecting the panel unit and the driving circuit unit will be explained. 
     FIGS. 2A through 2C illustrate the method for electrically connecting the panel unit and the PDP driving circuit of FIG.  1 . 
     FIG. 2A illustrates a structure of the PDP apparatus in which the driving circuit unit, namely, a PCB substrate  101  is disposed under the panel unit  100 , and the electrodes of the panel unit  100  and the driving circuit of the PCB substrate  101  are connected by a conductive rubber  102 . 
     FIG. 2B illustrates a structure that the PCB substrate  104  is installed near the panel unit  103 , and the panel unit  103  and the PCB substrate  104  are connected by a thermal pressing method. 
     FIG. 2C illustrates a method for installing the PCB substrate  107  under the panel unit  106  and connecting the electrodes of the panel unit  106  and the driving circuit of the PCB substrate by disposing therebetween a flexible printed circuit  108  formed of an anisotropic conductive film. 
     However, in the above-described conventional PDP apparatus, since the PCB having the panel unit and driving circuit is formed at different substrates, respectively, the size and weight of the PDP apparatus are increased. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a PDP apparatus which is capable of significantly decreasing a size and weight of a PDP apparatus by integrally forming a panel unit and driving circuit unit on a single substrate. 
     To achieve the above object, there is provided a PDP apparatus in which a panel unit(discharge cell) is formed on one surface of a flat metallic substrate, and a driving circuit unit is installed on another surface thereof. 
     To achieve the above object, there is provided a PDP apparatus according to the present invention which includes a metallic lower substrate, a first insulation layer formed on an upper surface of one side of the metallic lower substrate, an upper substrate formed opposite to the one side of the metallic lower substrate, a plurality of barriers formed between the metallic lower substrate and the upper substrate for defining a plurality of discharge spaces, and a second insulation layer formed on another surface of the metallic lower substrate and including the driving circuit unit thereon. 
     Additional advantages, objects and features of the invention will become more apparent from the description which follows. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: 
     FIG. 1 is an exploded perspective view illustrating a panel unit of a conventional PDP(Plasma Display Panel) apparatus; 
     FIGS. 2A through 2C are views illustrating an electrical connection structure of a panel unit and a driving circuit unit of a conventional PDP apparatus; 
     FIG. 3 is a view illustrating a PDP apparatus according to a first embodiment of the present invention; 
     FIG. 4 is a view illustrating a PDP apparatus according to a second embodiment of the present invention; 
     FIG. 5 is a view illustrating a PDP apparatus according to a third embodiment of the present invention; and 
     FIG. 6 is a view illustrating a PDP apparatus according to a fourth embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The structure of a PDP(Plasma Display Panel) apparatus according to the present invention will be explained with reference to the accompanying drawings. 
     FIG. 3 is a vertical cross-sectional view illustrating the PDP apparatus according to the present invention. As shown therein, a plate shaped metallic substrate  200  is provided. A panel unit  220  of a PDP apparatus is formed on the metallic substrate  200 , and a PDP driving circuit unit  240  is formed under the metallic substrate  200 . 
     The driving circuit unit  240  will be explained. 
     A first insulation layer  212  is formed on a lower surface of the metallic substrate  200 . The first insulation layer  212  is preferably formed of a green tape. The first insulation layer  212  may be formed of one layer of the green tape. A plurality of layers of the green tape may be stacked. 
     A driving circuit  214  formed of wires for connecting the driving circuit integration device and integration circuit device is disposed on the surface of the first insulation layer  212  for driving the PDP apparatus. Namely, the metallic substrate  200  operates as a base plate of a PCB(Printed Circuit Board). The driving circuits are formed on the lower surface of the metallic substrate  200  which operates as the base plate. 
     Therefore, the metallic substrate  200  operates as a rear substrate of the panel unit of the PDP and is used as a base plate of the PCB. 
     Next, the panel unit  220  formed of a plurality of discharge cells between two opposite substrates will be explained. 
     A second insulation layer  202  is formed on an upper surface of the metallic substrate. A plurality of address electrodes  204  are formed in parallel at a certain distance from each other on the upper surface of the second insulation layer  202 . In addition, A barrier  208  is formed between the neighboring address electrodes  204  and on the upper surface of the second insulation layer  202  for separating each discharge cell  206 . The barrier  208  may be formed by a mold method using a green tape, and may be formed by a screen painting method using an insulation paste and may be formed by a known barrier formation method. In addition, the second insulation layer  202  is preferably formed of a green tape. A glass substrate  210  is installed on an upper portion of the barrier  208 . Here, the metallic substrate  200  is a rear substrate of the PDP, and a plurality of discharge cells  206  which are defined by each barrier  208  are formed between the rear substrate  200  and the front substrate  210 . 
     The driving circuit of the driving circuit unit and the electrode installed at the PDP panel unit are connected as follows. Namely, a through hole  250  is formed at an edge portion of the metallic substrate  200 , and an insulation film  252  is coated on an inner wall of the through hole  250 . A conductive plug  254  is formed in the through hole  250 . 
     Namely, the through hole  250  is formed at the metallic substrate  200 , and the insulation film  252  is coated on an inner wall of the through hole  250 . In addition, the conductive plug  254  is formed in the through hole  200  surrounded by the insulation film  252 . The panel unit of the PDP and the driving circuit unit are electrically connected by the conductive plug  254 . 
     Therefore, in the present invention, it is possible to implement an integral panel unit and driving unit by patterning a circuit on the green tape attached to a lower portion of the metallic substrate and mounting the PDP driving integration circuit device. As a result, the weight and size of the PDP apparatus are decreased, and the thickness of the same is decreased. In addition, it is possible to implement a small size and light and thin system. 
     FIG. 4 is a view illustrating a PDP apparatus according to a second embodiment of the present invention. As shown therein, the elements of the second embodiment of the present invention is the same as the first embodiment of the present invention, but a method according to the second embodiment of the present invention for connecting the electrodes of the PDP panel unit and the driving circuits is different from the first embodiment of the present invention. The same reference numerals of the first and second embodiments of the present invention are given to the same elements of the same. The same elements as the elements of the first embodiment will not be described. 
     In the PDP apparatus according to the second embodiment of the present invention, an insulation member  401  is formed on an outer circumferential surface of the metallic substrate  200 , and the electrical connection portions of the PDP panel unit  220  and the driving circuit unit  240  are formed at the insulation member  401 . In the present invention, the insulation body is formed of a green tape. 
     Namely, an insulation member  401  is formed at an edge portion of the metallic substrate  200 , and a through hole  402  is formed at the insulation member  401 . A conductive plug  403  is filled in the through hole  402 . The PDP panel unit and the driving circuits are connected by the conductive plug  403 . 
     The connection structure of the address electrode and driving circuit of the rear substrate is described with reference to FIGS. 3 and 4. FIG. 5 illustrates a connection structure of the sustain electrode and driving circuit. 
     As shown therein, a connection structure for connecting a front surface  500 , a front substrate  500  and a sustain electrode  502 , and the sustain electrode and the driving circuit is newly added. The remaining elements are the same as the embodiment shown in FIGS. 3 and 4. The same elements as the first and second embodiments of the present invention are given by the same reference numerals. 
     The structure for connecting the sustain electrodes and the PDP driving circuit of the front substrate will be explained. 
     First, a through hole  510  which passes through the first insulation layer  212  and the second insulation layer  202  formed at the metallic substrate  200  is formed at an edge portion of the metallic substrate  200 . An insulation film  512  is coated on an inner wall of the through hole  510 , and a conductive plug  514  is formed in the through hole  510  of the inner side of the insulation film  512 . An end portion  514 a of the conductive plug  514 , namely, an end portion of the metallic substrate  200  is connected with the PDP driving circuit formed on the surface of the second insulation film  212  formed on the lower surface of the metallic substrate  200 . In addition, the other end portion  514   b  of the conductive plug  514 , namely, an end portion of the metallic substrate  200  is connected with the sustain electrode  502  installed at the front substrate  500 . 
     In particular, the upper end portion  514   b  of the conductive plug and the sustain electrode  502  of the front substrate  500  are electrically connected by a solder bump  516 . 
     FIG. 6 illustrates another embodiment of the connection structure for connecting the electrodes and the driving circuits of the front substrate. The elements of this embodiment of the present invention are the same as the elements shown in FIGS. 3 and 4 except for the construction of a front substrate  600  and a sustain electrode  602  and a connection structure for connecting the electrodes and driving circuits of the front substrate. Therefore, the description of the same elements will be omitted except for the connection structure for connecting the sustain electrodes and the driving circuits of the front substrate. 
     An insulation member  610  formed of a green tape is formed at an edge portion of the metallic substrate  200 . A through hole  612  is formed at the insulation member  610 . A conductive plug  614  is formed in the through hole  612 . A lower portion  614 a of the conductive plug  614  is electrically connected with the driving circuit  215 , and an upper portion  614 b of the conductive plug  614  is connected with the sustain electrode  602  formed at the front substrate  600  by a solder bump  616 . 
     As described above, in the PDP apparatus according to the present invention, it is possible to implement a thin and light PDP apparatus by integrally forming the driving circuit unit and the panel unit. 
     Although the preferred embodiment of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as recited in the accompanying claims.