Patent Publication Number: US-8120374-B2

Title: Inspection circuit and display device thereof

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an inspection circuit and a display device thereof, and more particularly, to an inspection circuit with shorting switches respectively disposed on different sides of the pixel area of the display device for reducing the cross-talk and the coupling effect. 
     2. Description of the Prior Art 
     Please refer to  FIG. 1 .  FIG. 1  is a diagram illustrating a conventional Liquid Crystal Display (LCD)  100  during the inspection phase. The inspection type is 2G3D, which means all the gate lines are short-circuited to only two gate lines (2G), and all the data lines are short-circuited to only three data lines (3D). As shown in  FIG. 1 , during the inspection phase, the LCD  100  comprises an inspection circuit  140  and a pixel area (display area)  110 . 
     The inspection circuit  140  is utilized for inspecting if there is any bad pixel in the pixel area  110 . The inspection circuit  140  comprises two gate line shorting bars GSL A  and GSL B , three data line shorting bars DSL C , DSL D  and DSL E , and five conducting pads GA, GB, C, D and E. The conducting pads GA, GB, C, D and E are respectively electrically connected to the gate shorting bar GSL A , the gate shorting bar GSL B , the data shorting bar DSL C , the data shorting bar DSL D , and the data shorting bar DSL E . 
     The pixel are  110  comprises N gate lines (signal wires) GL 1 ˜GL N , M data lines (signal wires) DL 1 ˜DL M  and a plurality of pixels interwoven by the gate lines and the data lines. The gate lines GL 1 ˜GL N  are divided into two groups: an odd gate line group (for example, GL 1 , GL 3 , GL 5  and so on), and an even gate line group (for example, GL 2 , GL 4 , GL 6  and so on). The data lines DL 1 ˜DL M  are divided into three groups: a red data line group (for example, DL 1 , DL 4 , DL 7  and so on), a green data line group (for example, DL 2 , DL 5 , DL 8  and so on), and a blue data line group (for example, DL 3 , DL 6 , DL 9  and so on). Each gate line comprises a first end  1  and a second end  2 . For instance, the gate line GL 1  comprises a first end  1  and a second end  2 . Each data line comprises a first end  1  and second end  2 . For instance, the data line DL 1  comprises a first end  1  and a second end  2 . 
     Each pixel in the pixel area  110  comprises three sub-pixels (a red sub-pixel, a green sub-pixel, and a blue sub-pixel). As shown in  FIG. 1 , a red sub-pixel PX 11  is electrically connected through a pixel switch SW P11  to the corresponding gate line and the corresponding red data line so as to receive the corresponding gate driving signal and the corresponding data driving signal for driving the red sub-pixel PX 11  (it means displaying red color). More particularly, a first end  1  of the pixel switch SW P11  is electrically connected to the red data line DL 1 , a second end  2  of the pixel switch SW P11  is electrically connected to the red sub-pixel PX 11 , and a control end C of the pixel switch SW P11  is electrically connected to the gate line GL 1 . When the LCD  100  is during the inspection phase, all the gate lines GL 1 ˜GL N  are respectively short-circuited with the two gate line shorting bars GSL A , and GSL B , and all the data lines DL 1 ˜DL M  are respectively short-circuited with the three data line shorting bars DSL C , DSL D , and DSL E . The inspection signals are respectively inputted to the conducting pads GA, GB, C, D and E for inspecting if there is any bad pixel in the pixel area  110 . 
     As shown in  FIG. 1 , after the inspection phase, a laser cut procedure is executed for cutting out the inspection circuit  140  from the LCD  100 . After that the laser cut procedure, the gate driving circuit (signal driving circuit)  120  and the data driving circuit (signal driving circuit)  130  are respectively electrically connected to the corresponding conducting pads P G1 ˜P GN  and P D1 ˜P DM . Moreover, the output ends of the gate driving circuit  120  are respectively electrically connected through the conducting pads P G1 ˜P GN  to the first ends  1  of the gate lines GL 1 ˜GL N  and the output ends of the data driving circuit  130  are respectively electrically connected through the conducting pads P D1 ˜P DM  to the first ends  1  of the data lines DL 1 ˜DL M . In this way, the fabrication of the LCD  100  is done. 
     However, after the inspection phase, the conventional inspection circuit  140  has to be cut out from the LCD by laser procedure, which causes a higher cost and a great inconvenience. 
     SUMMARY OF THE INVENTION 
     The present invention provides an inspection circuit for inspecting a plurality of signal wires of a display area. Each signal wire has a first end for electrically connecting to a signal driving circuit and a second end. The inspection circuit comprises a first signal wire shorting switch and a second signal wire shorting switch. The first signal wire shorting switch comprises a first end, electrically connected to the first end of a first signal wire of the plurality of the signal wires, a second end, and a third end for receiving a first control signal. The first signal wire shorting switch controls the first end of the first signal wire shorting switch electrically connecting to the second end of the first signal wire shorting switch according to the first control signal. The second signal wire shorting switch comprises a first end, electrically connected to the second end of the first signal wire of the plurality of the signal wires, a second end, electrically connected to the second end of a second signal wire of the plurality of the signal wires, and a third end for receiving a second control signal. The second signal wire shorting switch controls the first end of the second signal wire shorting switch electrically connecting to the second end of the second signal wire shorting switch according to the second control signal. 
     The present invention further provides an inspection circuit for inspecting a plurality of signal wires of a display area. Each of the plurality of the signal wires has a first end disposed on a first side of the display area for electrically connecting to a signal driving circuit and a second end disposed on a second side different from the first side of the display area. The inspection circuit comprises a shorting bar, a plurality of first signal wire shorting switches, and a plurality of second signal wire shorting switches. The shorting bar is disposed on the first side of the display area for receiving an inspection signal to inspect the plurality of the signal wires. The plurality of first signal wire shorting switches are disposed on the first side of the display area. Each of the plurality of the first signal wire shorting switches comprises a first end, electrically connected to the first end of a corresponding signal wire of the plurality of the signal wires, a second end, electrically connected to the shorting bar, and a third end for receiving a first control signal. The first signal wire shorting switch controls the first end of the first signal wire shorting switch electrically connecting to the second end of the first signal wire shorting switch according to the first control signal. The plurality of second signal wire shorting switches are disposed on the second side of the display area. Each of the plurality of the second signal wire shorting switches corresponds to a first signal wire shorting switch. Each of the plurality of the second signal wire shorting switches comprises a first end electrically connected to the second end of a signal wire electrically connected to a corresponding signal wire short switch of the plurality of the first signal wire shorting switches, a second end electrically connected to the second end of a corresponding signal wire of the plurality of the signal wires, which is different from the signal wire electrically connected to the first end of the second signal wire shorting switch, and a third end for receiving a second control signal. The second signal wire shorting switch controls the first end of the second signal wire shorting switch electrically connecting to the second end of the second signal wire shorting switch according to the second control signal. 
     The present invention further provides a display device. The display device comprises a display area, and an inspection circuit. The display area comprises a plurality of pixels, a plurality of pixel switches for driving the plurality of the pixels, and a plurality of signal wires for transmitting signals to the plurality of the pixel switches. Each of the plurality of the signal wires comprises a first end disposed on a first side of the display area and a second end disposed on a second side different from the first side of the display area. The inspection circuit comprises a shorting bar, a plurality of first signal wire shorting switches, and a plurality of second signal wire shorting switches. The shorting bar is disposed on the first side of the display area for receiving an inspection signal to inspect the plurality of the signal wires. The plurality of first signal wire shorting switches are disposed on the first side of the display area. Each of the plurality of the first signal wire shorting switches is electrically connected between the shorting bar and the first end of a corresponding signal wire of the plurality of the signal wires. The plurality of second signal wire shorting switches are disposed on the second side of the display area. Each of the plurality of the second signal wire shorting switches corresponds to one of the plurality of the first signal wire shorting switches. Each of the plurality of the second signal wire shorting switches is electrically connected between the second end of the signal wire electrically connected to the first signal wire shorting switch corresponding to the second signal wire switch and the second end of a signal wire corresponding to the second signal wire shorting switch. Each of the plurality of the second signal wire shorting switches is electrically connected between different signal wires of the plurality of the signal wires. 
     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating a conventional LCD during the inspection phase. 
         FIG. 2  is a diagram illustrating the LCD according to the first embodiment of the present invention during the inspection phase. 
         FIG. 3  is a diagram illustrating the gate lines being short-circuited during the inspection phase. 
         FIG. 4  is a diagram illustrating the data lines being short-circuited during the inspection phase. 
         FIG. 5  is a diagram illustrating the LCD according to the second embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Certain terms are used throughout the description and following claims to refer to particular components. As one skilled in the art will appreciate, electronic equipment manufacturers may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms “include” and “comprise” are used in an open-ended fashion, and thus should be interpreted to mean “include, but not limited to . . . .” Also, the term “electrically connect” is intended to mean either an indirect or direct electrical connection. Accordingly, if one device is coupled to another device, that connection may be through a direct electrical connection, or through an indirect electrical connection via other devices and connections. 
     Please refer to  FIG. 2 .  FIG. 2  is a diagram illustrating an LCD  200  (2G3D), during the inspection phase, according to the first embodiment of the present invention. The LCD  200  comprises an inspection circuit  240 , and a pixel area (display area)  210 . 
     The pixel area  210  comprises N gate lines (signal wires) GL 1 ˜GL N , M data lines (signal wires) DL 1 ˜DL M  and a plurality of pixels interwoven by the gate lines and the data lines. The gate lines GL 1 ˜GL N  are divided into two groups: an odd gate line group (for example, GL 1 , GL 3 , GL 5  and so on) and an even gate line group (for example, GL 2 , GL 4 , GL 6  and so on). The data lines DL 1 ˜DL M  are divided into three groups: a red data line group (for example, DL 1 , DL 4 , DL 7  and so on), a green data line group (for example, DL 2 , DL 5 , DL 8  and so on), and a blue data line group (for example, DL 3 , DL 6 , DL 9  and so on). Each gate line comprises a first end  1  and a second end  2 . For instance, the gate line GL 1  comprises a first end  1  and a second end  2 . Each data line comprises a first end  1  and a second end  2 . For instance, the data line DL 1  comprises a first end  1  and a second end  2 . Each pixel in the pixel area  210  comprises three sub-pixels (a red sub-pixel, a green sub-pixel, and a blue sub-pixel). As shown in  FIG. 2 , a red sub-pixel PX 11  is electrically connected through a pixel switch SW P11  to the corresponding gate line and the corresponding red data line so as to receive the corresponding gate driving signal and the corresponding data driving signal for driving the red sub-pixel PX 11  (it means displaying red color). More particularly, a first end  1  of the pixel switch SW P11  is electrically connected to the red data line DL 1 , a second end  2  of the pixel switch SW P11  is electrically connected to the red sub pixel PX 11 , and a control end C of the pixel switch SW P11  is electrically connected to the gate line GL 1 . 
     The inspection circuit  240  comprises two gate line shorting bars GSL A  and GSL B , three data line shorting bars DSL C , DSL D  and DSL E , five conducting pads GA, GB, C, D and E, N gate line shorting switches (signal wire shorting switches) SW G1 ˜SW GN  and M data line shorting switches (signal wire shorting switches) SW D1 ˜SW DM . As shown in  FIG. 2 , the gate line shorting bars GSL A  and GSL B  are disposed on the left side of the pixel area  210  and the data line shorting bars DSL C , DSL D  and DSL E  are disposed on the bottom side of the pixel area  210 . The conducting pads GA, GB, C, D and E are respectively electrically connected to the gate line shorting bar GSL A , the gate line shorting bar GSL B , the data line shorting bar DSL C , the data line shorting bar DSL D  and the data line shorting bar DSL E . 
     In addition, the conducting pads P G1 ˜P GN  are disposed on the left side of the pixel area  210  for electrically connecting the gate driving circuit (signal driving circuit)  220  to the gate lines GL 1 ˜GL N  after the inspection phase. More precisely, after the inspection phase, the gate driving circuit  220  is electrically connected to the corresponding conducting pads P G1 ˜P GN  so as to electrically connect the output ends of the gate driving circuit  220  through the conducting pads P G1 ˜P GN  to the first ends  1  of the gate lines GL 1 ˜GL N . The conducting pads P D1 ˜P DM  are disposed on the bottom side of the pixel area  210  for electrically connecting the data driving circuit (signal driving circuit)  220  to the data lines DL 1 ˜DL M  after the inspection phase. More precisely, after the inspection phase, the data driving circuit  230  is electrically connected to the corresponding conducting pads P D1 ˜P DM  so as to electrically connect the output ends of the data driving circuit  230  through the conducting pads to the first ends  1  of the data lines DL 1 ˜GL M . 
     All the gate line shorting switches SW G1 ˜SW GN  and the data line shorting switches SW D1 ˜SW DM  have the same structure. For instance, the gate line shorting switch SW G1  comprises a first end  1 , a second end  2 , and a control end C. The gate line shorting switch SW G1  controls the first end  1  of the gate line shorting switch SW G1  electrically connecting to the second end  2  of the gate line shorting switch SW G1  according to the control signal S CG1  received on the control end C of the gate line shorting switch SW G1 . For instance, when the control signal S CG1  turns on the gate line shorting switch SW G1 , the first end  1  of the gate line shorting switch SW G1  is electrically connected to the second end  2  of the gate line shorting switch SW G1 . On the contrary, when the control signal S CG1  turns off the gate line shorting switch SW G1 , the electrical connection between the first end  1  of the gate line shorting switch SW G1  and the second end  2  of the gate line shorting switch SW G1  is broken (open-circuited). The data line shorting switch SW D1  comprises a first end  1 , a second end  2 , and a control end C. The data line shorting switch SW D1  controls the first end  1  of the data line shorting switch SW D1  electrically connecting to the second end  2  of the data line shorting switch SW D1  according to the control signal S CD1  received on the control end C of the data line shorting switch S WD1 . For instance, when the control signal S CD1  turns on the data line shorting switch SW D1 , the first end  1  of the data line shorting switch SW D1  is electrically connected to the second end  2  of the data line shorting switch SW D1 . On the contrary, when the control signal S CD1  turns off the data line shorting switch SW D1 , the electrical connection between the first end  1  of the data line shorting switch SW D1  and the second end  2  of the data line shorting switch SW D1  is broken (open-circuited). 
     The gate line shorting switches SW G1 ˜SW GN  are respectively disposed on the left side and the right side of the pixel area  210  for increasing available space between any two adjacent gate line shorting switches. That is, the gate line shorting switches SW G1 ˜SW GN  are respectively disposed on the left side and the right side of the pixel area  210  so that the distance between any two adjacent gate line shorting switches becomes longer so as to reduce the cross-talk and the coupling effect. 
     The data line shorting switches SW D1 ˜SW DM  are respectively disposed on the upper side and the bottom side of the pixel area  210  for increasing available space between any two adjacent data line shorting switches. That is, the data line shorting switches SW D1 ˜SW GM  are respectively disposed on the upper side and the bottom side of the pixel area  210  so that the distance between any two adjacent data line shorting switches becomes longer so as to reduce the cross-talk and the coupling effect. 
     The gate line shorting switches SW G1 ˜SW GN  of the inspection circuit  240  are divided into two groups: an odd gate shorting switch group (for example, SW G1 , SW G3 , SW G5  and so on), and an even gate shorting switch group (for example, SW G2 , SW G4 , SW G6  and so on). Any two adjacent gate lines in the same group are respectively named as the first gate line and the second gate line hereinafter. The gate line shorting switch corresponding to the first gate line and the gate line shorting switch corresponding to the second gate line are respectively disposed on the left side of the pixel area  210  and the right side of the pixel area  210 . More particularly, the first end  1  of the gate line shorting switch corresponding to the first gate line is electrically connected to the first end  1  of the first gate line; the second end  2  of the gate line shorting switch corresponding to the first gate line is electrically connected to the corresponding odd/even gate line shorting bar; the first end  1  of the gate line shorting switch corresponding to the second gate line is electrically connected to the second end  2  of the first gate line; the second end  2  of the gate line shorting switch corresponding to the second gate line is electrically connected to the second end  2  of the second gate line. For example, among the odd gate line shorting switch group, the gate line shorting switches corresponding to the two adjacent odd gate lines GL 1  and GL 3  are the gate line shorting switches SW G1  and SW G3 . The first end  1  of the gate line shorting switch SW G1  is electrically connected to the first end  1  of the gate line GL 1 ; the second end  2  of the gate line shorting switch SW G1  is electrically connected to the gate line shorting bar GSL A . The first end  1  of the gate line shorting switch SW G3  is electrically connected to the second end  2  of the gate line GL 1 ; the second end  2  of the gate line shorting switch SW G3  is electrically connected to the second end  2  of the gate line GL 3 . The rest gate line shorting switches of the odd gate line shorting switch group are disposed in the same way. The gate line short switches of the even gate line shorting switch group are disposed in the similar way as the gate line shorting switches of the odd gate line shorting switch group disposed and hereinafter will not be repeated again for brevity. 
     The data line shorting switches SW D1 ˜SW DM  of the inspection circuit  240  are divided into three groups: a red data shorting switch group (for example, SW D1 , SW D4 , SW D7  and so on), a green data shorting switch group (for example, SW D2 , SW D5 , SW D8  and so on), and a blue data shorting switch group (for example, SW D3 , SW D6 , SW D9  and so on). Any two adjacent data lines in the same group are respectively named as the first data line and the second data line in the following description. The data shorting switch corresponding to the first data line and the data line shorting switch corresponding to the second data line are respectively disposed on the upper side of the pixel area  210  and the bottom side of the pixel area  210 . More particularly, the first end  1  of the data line shorting switch corresponding to the first data line is electrically connected to the first end  1  of the first data line; the second end  2  of the data line shorting switch corresponding to the first data line is electrically connected to the corresponding data line shorting bar DSL C  or DSL D  or DSL E ; the first end  1  of the data line shorting switch corresponding to the second data line is electrically connected to the second end  2  of the first data line; the second end  2  of the data line shorting switch corresponding to the second data line is electrically connected to the second end  2  of the second data line. For example, among the red data line shorting switch group, the data line shorting switches corresponding to the two adjacent red data lines DL 1  and DL 4  are the data line shorting switches SW D1  and SW D4 . The first end  1  of the data line shorting switch SW D1  is electrically connected to the first end  1  of the data line DL 1 ; the second end  2  of the data line shorting switch SW D1  is electrically connected to the data line shorting bar DSL C . The first end  1  of the data line shorting switch SW D4  is electrically connected to the second end  2  of the data line DL 1 ; the second end  2  of the data line shorting switch SW D4  is electrically connected to the second end  2  of the data line DL 4 . The rest data line shorting switches of the red data line shorting switch group are disposed in the same way. The data line short switches of the green and the blue data line shorting switch groups are disposed in the similar way as the data line shorting switches of the red data line shorting switch group disposed and hereinafter will not be repeated again for brevity. 
     Please refer to  FIG. 3 .  FIG. 3  is a diagram illustrating the gate lines being short-circuited during the inspection phase. As shown in  FIG. 3 , during the inspection phase, by means of the inspection circuit  240 , all the gate line shorting switches SW G1 ˜SW GN  are turned on so that all the gate lines are short-circuited to the corresponding gate line shorting bars as shown in  FIG. 3 . In this way, the inspection signals can be transmitted to the conducting pads GA and GB through the corresponding gate line shorting bars for inspecting all the gate lines GL 1 ˜GL N . 
     Please refer to  FIG. 4 .  FIG. 4  is a diagram illustrating the data lines being short-circuited during the inspection phase. As shown in  FIG. 4 , during the inspection phase, by means of the inspection circuit  240 , all the data line shorting switches SW D1 ˜SW DM  are turned on so that all the data lines are short-circuited to the corresponding data line shorting bars as shown in  FIG. 4 . In this way, the inspection signals can be transmitted to the conducting pads C, D and E through the corresponding data line shorting bars for inspecting all the data lines DL 1 ˜DL M . 
     In addition, the control ends C of each of the shorting switches SW G1 ˜SW GN  and SW D1 ˜SW DN  can be totally electrically connected together or partially electrically connected together as desired. However, it is required that all the shorting switches SW G1 ˜SW GN  and SW D1 ˜SW DM  have to be turned on during the inspection phase, and after the inspection phase, all the shorting switches SW G1 ˜SW GN  and SW D1 ˜SW DM  have to be turned off for preventing the LCD  200  from abnormal operation since the gate driving circuit  220  and the data driving circuit  230  are respectively electrically connected to the conducting pads PG 1 ˜PG N  and PD 1 ˜PD M . 
     Please refer to  FIG. 5 .  FIG. 5  is a diagram illustrating the LCD  500  (2G2D) according to the second embodiment of the present invention. As shown in  FIG. 5 , the LCD  500  comprises an inspection circuit  540  and a pixel area (display area)  510 . The inspection circuit  540  and the pixel area  510  in the LCD  500  are similar to the inspection circuit  240  and the pixel area  210  in the LCD  200 . The only difference is that the inspection circuit  540  comprises two gate line shorting bars GSL A  and GSL B , two data line shorting bars DSL C  and DSL D , and four conducting pads GA, GB, C and D. Compared with the inspection circuit  240 , only two data line shorting bars are utilized in the inspection circuit  540  for shorting-circuited function. The pixel area  510  is divided into groups according to the design of the shorting bars of the inspection circuit  540 . The related operational principle is as described above and hereinafter will not be repeated again. 
     In conclusion, the inspection circuit provided by the present invention increases the space between any two adjacent shorting switches by disposing the shorting switches on the different sides of the pixel area. Meanwhile, the cross-talk and coupling effect between the shorting switches are reduced, causing a great convenience. 
     Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention.