Abstract:
A testing apparatus for flat-panel display is disclosed. The flat-panel display at least comprises a plurality of electrode lines and a plurality of driving circuits. The driving circuits are used to drive the electrode lines. The driving circuits and the testing apparatus are disposed on the opposite sides of the flat-panel display. The testing apparatus comprises a plurality of switching components and at least one shorting bar. The shorting bar electrically couples to the electrode lines through the switching components. When the switching components are thin film transistor, the switching components further comprise at least one switching line. The switching line electrically couples to the gates of the thin film transistors. The electrode lines are divided into several groups to electrically couple to the shorting bar and the switching line, for example.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application claims the priority benefit of Taiwan application serial no. 93100024, filed Jan. 2, 2004. 
   BACKGROUND OF INVENTION 
   1. Field of the Invention 
   The present invention relates to a testing apparatus for a flat-panel display, and more particularly, to a flat-panel display testing apparatus in which the electrode lines are tested in groups and the lines electrically coupling the electrode lines and the testing apparatus need not be cut off after the testing is completed. 
   2. Description of Related Art 
   The Information Technology (IT) industry is a mainstream industry in modern life. Especially, the display product for various portable communication devices has become an important development subject in this field. Presently flat panel is popularly used because of its advantageous features of high picture quality, small space utilization, low power consumption and radiation free. Therefore, the flat-panel display, which works as a communication interface between users and information, has accordingly become a very important tool in our every day activities. The flat-panel display is classified in the following categories: the Organic Electro-Luminescent Display, OELD), the Plasma Display Panel (PDP), the Liquid Crystal Display (LCD), the Light Emitting Diode (LED), the Vacuum Fluorescent Display, the Field Emission Display (FED), and the Electro-chromic Display. After the flat-panel display is manufactured, it must be tested to ensure of its proper operation before it is shipped to the customer. 
   An apparatus and a method of testing a Thin Film Transistor Liquid Crystal Display (TFT LCD) are described as follows.  FIG. 1  is a circuit diagram of a apparatus for testing a conventional TFT LCD. As shown in  FIG. 1 , the TFT LCD  100  is defined into a display area  110  and a peripheral area  120 . Wherein, a plurality of electrode lines  130  is disposed on the display area  110 , and a plurality of driving circuits  140  is disposed on the peripheral area  120  for driving the electrode lines  130 . For testing the TFT LCD, a shorting bar  150  is electrically coupled to the electrode lines  130  and then a signal is fed into the electrode lines  130  via the shorting bar  150 . to check for its proper operation. 
   After completing the above test, the lines used for an electrically coupling the shorting bar  150  and electrode lines  130  of the TFT LCD  100  are cut to disconnect or separate the shorting bar  150  from the TFT LCD  100 . However, the step of cutting the lines electrically coupling the shorting bar  150  and the electrode lines inevitably consumes time and thereby increasing the manufacturing cost. 
     FIG. 2  is a circuit diagram of a testing apparatus for testing a conventional TFT LCD. As shown in  FIG. 2 , a shorting bar  152  is disposed in a peripheral area  122  of the TFT LCD  102  and is electrically coupled to the electrode lines  132 . The TFT LCD  102  is tested by feeding a signal into the electrode lines  132  via the shorting bar  152 . After the testing of the TFT LCD  102  is completed, a laser beam is used for cutting the lines electrically coupling the shorting bar  152  and the electrode lines of the TFT LCD  102 . However, the shorting bar  152  still remains within the TFT LCD  102  in this case. 
   Although the aforementioned laser cutting step is rather simple, but since the shorting bar  152  and the driving circuits  142  are disposed in the peripheral area  122 , and therefore the size of the TFT LCD  102  is hard to reduce. 
   SUMMARY OF INVENTION 
   Accordingly, the present invention is directed to a testing apparatus of a flat-panel display. The testing apparatus is capable of testing the electrode lines of the flat-panel display in groups, and the lines electrically coupling the electrode lines and the testing apparatus need not be cut after the testing is completed. Further, such that the size of the testing apparatus is smaller compared to the conventional testing apparatus allowing further reduction the size of the flat-panel display. 
   According to an embodiment of the present invention, the flat-panel display to be tested at least comprises a plurality of electrode lines and a plurality of driving circuits. Wherein, the driving circuits are used for driving the electrode lines and are disposed on a first side of the flat-panel display. 
   The testing apparatus comprises a plurality of switching components and at least a shorting bar. The switching components are electrically coupled to the electrode lines and are disposed on a second side of the flat-panel display. The shorting bar is electrically coupled to the switching components. In addition, the first side is positioned opposite to the second side. In other words, the shorting bar and the driving circuits are respectively disposed on two opposite sides of the display area of the flat-panel display. 
   In an embodiment of the present invention, each of the switching components comprises one or more diodes, or comprises one or more TFT. The electrode lines are for example the data lines or the scan lines. 
   In an embodiment of the present invention, the flat-panel display comprises at least a plurality of electrode lines and a plurality of driving circuits. The driving circuits are adapted for driving the electrode lines. 
   In an embodiment of the present invention, the testing apparatus comprises a plurality of switching components, a switching set, and a plurality of shorting bars. Each of the switching components comprises a gate, a first source/drain, and a second source/drain. The first source/drain is electrically coupled to the electrode lines. The switching set is electrically coupled to the gates of the switching components. In addition, each of the shorting bars is electrically coupled to the second sources/drains of some of the switching components. 
   In an embodiment, when the switching set comprises a plurality of switching lines, each of the switching lines are electrically coupled to the gates of some switching components. Moreover, each of the switching components is, for example, comprised of one or more TFT, and the electrode lines are, for example, the data lines or the scan lines. 
   In another embodiment of the present invention, the testing apparatus comprises a plurality of switching components, a plurality of switching lines and a shorting bar. Each of the switching components comprises a gate, a first source/drain, and a second source/drain. The first source/drain is electrically coupled to the electrode lines. The switching lines are electrically coupled to the gates of the switching components, and each of the switching lines is electrically coupled to the gates of some of switching components. In addition, the shorting bar is electrically coupled to the second sources/drains of the switching components. 
   In addition, each of the switching components is, for example, comprised of one or more TFT, and the electrode lines are, for example, the data lines or the scan lines. 
   In another embodiment of the present invention, the testing apparatus comprises a plurality of switching components and a shorting bar set. The switching components are electrically coupled to the electrode lines, and the shorting bar set is electrically coupled to the switching components. 
   In an embodiment, when the shorting bar set comprises a plurality of shorting bars, each of the shorting bars is electrically coupled to some of the switching components. Moreover, each of the switching components is, for example, comprised of a diode, and the electrode lines are, for example, the data lines or the scan lines. 
   In summary, in the testing apparatus for the flat-panel display according to an embodiment of the present invention, the shorting bar and the driving circuits are disposed on the opposite sides of the display area of the flat-panel display, respectively, thus this allows further reduction in the size of the flat-panel display. In addition, since the switching components are in a high impedance state (almost as an open circuit state) in the normal operation, the step of cutting the lines electrically coupling the shorting bar and the electrode lines after the testing is completed can be eliminated. Moreover, the electrode lines of the flat-panel display can be tested in groups. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
     The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention, and together with the description, serve to explain the principles of the invention. 
       FIG. 1  is a circuit diagram of a conventional testing apparatus for a conventional TFT LCD. 
       FIG. 2  is a circuit diagram of another conventional testing apparatus for a conventional TFT LCD. 
       FIGS. 3A and 3B  are the circuit diagrams of a testing apparatus for a flat-panel display according to a first embodiment of the present invention. 
       FIG. 4  is a circuit diagram of switching components composed of the TFT according to an embodiment of the present invention. 
       FIG. 5A˜5C  are the circuit diagrams of a testing apparatus for a flat-panel display according to a second embodiment of the present invention. 
       FIG. 6  is a circuit diagram of a testing apparatus for a flat-panel display according to a third embodiment of the present invention. 
   

   DETAILED DESCRIPTION 
   First Embodiment 
     FIGS. 3A and 3B  are the circuit diagrams of a testing apparatus for a flat-panel display according to a first embodiment of the present invention. As shown in  FIGS. 3A and 3B , the flat-panel display  200  comprises at least a plurality of electrode lines  230  and a plurality of driving circuits  240 . The driving circuits  240  are adapted for driving the electrode lines  230 , and are disposed on a first side S 1  of the flat-panel display  200 . 
   The testing apparatus  250  comprises a plurality of switching components  260  and at least one shorting bar  270 . The switching components  260  are electrically coupled to the electrode lines  230 , and are disposed on a second side S 2  of the flat-panel display  200 . The shorting bar  270  is electrically coupled to the switching components  260 . In addition, the first side S 1  is positioned opposite to the second side S 2 , that is the shorting bar  270  and the driving circuits  240  are disposed on the opposite sides of the flat-panel display  200 , respectively. 
   In the present embodiment shown in  FIG. 3A , each of the switching components  260  is, for example, composed of a TFT. The testing apparatus  250  further comprises at least one switching line  280 , which is electrically coupled to the switching components  260 .  FIG. 4  is a circuit diagram of switching components composed of the TFT according to an embodiment of the present invention. As shown in  FIG. 4 , in order to reduce the current leakage of the switching components  260 , the component switching  260  is not necessarily limited to be composed of only one TFT  262 , instead the switching components  260  may also be composed a plurality of TFT  262 . 
   In an embodiment shown in  FIG. 3B , the switching components  260  are, for example, composed of diodes. 
   Since the shorting bar  270  is disposed on the opposite side of the driving circuit  240 , and therefore the width of the first side S 1  of the flat-panel display  200  is reduced so that this design allows further size reduction of the flat-panel display  200 . In addition, since the shorting bar  270  is electrically coupled to the electrode lines  230  via the switching components  260 , the switching components  260  can be turned on only by applying a voltage to a switching line  280  (as shown in  FIG. 3A ) or applying a current to the shorting bar  270  (as shown in  FIG. 3B ). It should be noted that when a current is applied to the electrode lines  230 , the switching components  260  are not turned on. Therefore, after the testing of the flat-panel display  200  by the testing apparatus  250  is completed, even when the lines electrically coupling the testing apparatus  250  and the electrode lines  230  were not cut, the electrode lines  230  are not electrically coupled with each other via the testing apparatus  250 . 
   Referring to  FIGS. 3A and 3B , the electrode lines  230  are, for example, the data lines or the scan lines. The data lines are, for example, the electrode lines  230  which are vertically disposed, and the scan lines are the electrode lines  230  which are horizontally disposed. Therefore, the shorting bar  270  and the switching components  260  which are electrically coupled to the electrode lines  230  can be used to test the data lines and the scan lines of the flat-panel display  200  to check whether is the flat-panel display  200  properly. 
   Second Embodiment 
     FIG. 5A˜5C  are the circuit diagrams of the testing apparatus for the flat-panel display according to a second preferred embodiment of the present invention. The structure of the flat-panel display according to the second preferred embodiment is the same as that of the first preferred embodiment, and therefore detailed description thereof is not repeated hereinafter. However, the testing apparatus according to the second preferred embodiment of the present invention is not necessarily limited to be disposed on the opposite side of the driving circuit  240  as shown in  FIG. 3A , it can be disposed on the same side of the driving circuit  240 . 
   Referring to  FIG. 5A , the testing apparatus  350  comprises a plurality of switching components  360 , a plurality of switching lines  380   a , and a shorting bar  370 . Each of the switching components  360  comprises a gate  362 , a first source/drain  364 , and a second source/drain  366 , respectively. The first source/drain  364  is electrically coupled to the electrode lines  330 . Each of the switching lines  380   a  is electrically coupled to the gates  362  of some of the switching components  360 , respectively. The shorting bar  370  is electrically coupled to the second sources/drains  366  of all switching components  360 . The switching components  360  are, for example, composed of one or more TFT. 
   As described above, by selectively turning on the switching lines  380   a , the electrode lines  330  can be tested in groups. For example, the grouping of the electrode lines  330  can be based on the electrode lines  330  in a pixel area corresponding a unique color so that a pixel area of the same color can be tested at a time. In addition, the electrode lines  330  may be grouped based on other considerations. 
   Referring to  FIG. 5B , the testing apparatus  352  comprises a plurality of switching components  360 , a switching set  380 , and a plurality of shorting bars  370 . Each of the switching components  360  comprises a gate  362 , a first source/drain  364 , and a second source/drain  366 , respectively. The first source/drain  364  is electrically coupled to the electrode lines  330 . The switching set  380  comprises a plurality of switching lines  380   a , and each of the switching lines  380   a  is electrically coupled to the gates  362  of some of the switching components  360 , respectively. Each of the shorting bars  370  is electrically coupled to the second sources/drains  366  of some of the switching components  360 , respectively. In addition, the switching components  360  are, for example, composed of one or more TFT. Following the description above, by selectively turning on the switching lines  380   a  and the shorting bars  370 , the electrode lines  330  can be tested in groups. 
   Referring to  FIG. 5C , the testing apparatus  354  comprises a plurality of switching components  360 , a switching line  380   a , and a plurality of shorting bars  370 . Each of the switching components  360  comprises a gate  362 , a first source/drain  364 , and a second source/drain  366 , respectively. The first source/drain  364  is electrically coupled to the electrode lines  330 . The switching line  380   a  is electrically coupled to the gates  362  of all switching components  360 . Each of the shorting bars  370  is electrically coupled to the second sources/drains  366  of some of the switching components  360 . In addition, the switching components  360  are, for example. comprised of one or more TFT. Similarly, by selectively turning on the shorting bars  370 , the electrode lines  330  can be tested in groups. 
   Third Embodiment 
     FIG. 6  is a circuit diagram of a testing apparatus for the flat-panel display according to a third embodiment of the present invention. The structure of the flat-panel display of the third preferred embodiment of the present invention is same as that of the first preferred embodiment, and therefore detailed description thereof is not repeated hereinafter. However, the testing apparatus according to the third embodiment of the present invention is not necessarily limited to be disposed on the opposite side of the driving circuit  240  as shown in  FIG. 3B , it can be disposed on the same side of the driving circuit  240 . 
   Referring to  FIG. 6 , the testing apparatus  450  comprises a plurality of switching components  460  and a shorting bar set  470 . The shorting bar set  470  are, for example, composed of a plurality of shorting bars  470   a , and each of the shorting bars  470   a  is electrically coupled to some of the switching components  460 , respectively. In addition, the switching components  460  are, for example, composed of one or more diodes. By selectively turning on the shorting bars  470   a , the electrode lines  430  can be tested in groups. For example, the grouping of the electrode lines  430  can be based on the electrode lines  430  of a pixel area corresponding to a unique color so that a pixel area of the same color can be tested at a time. In addition, the electrode lines  430  may be grouped based on other considerations. 
   In summary, in the testing apparatus for the flat-panel display according to an embodiment of the present invention, the shorting bar and driving circuits are disposed on the opposite sides of the driving circuit  240  of the flat-panel display, and therefore this design allows further size reduction of the flat-panel display. In addition, since the shorting bar is electrically coupled to the electrode lines via the switching components, even when the lines electrically coupling the shorting bar and the electrode lines are not cut after the testing is completed, the electrode lines are not electrically coupled to each other since the switching components are turned off. Furthermore, by arranging the shorting bars and the switching lines in different manner, the electrode lines of the flat-panel display can be tested in groups. 
   Although the invention has been described with reference to a particular embodiment thereof, it will be apparent to one of the ordinary skill in the art that modifications to the described embodiment may be made without departing from the spirit of the invention. Accordingly, the scope of the invention will be defined by the attached claims not by the above detailed description.