Patent Application
20140001966
This application claims priority to and the benefit of Korean Patent Application No. 10-2012-0071792, filed in the Korean Intellectual Property Office on Jul. 2, 2012, the entire content of which is incorporated herein by reference.
(a) Field
Aspects of embodiments of the present invention relate to a static electricity preventing display panel, a manufacturing method of the static electricity preventing display panel, and a display device including the static electricity preventing display panel.
(b) Description of the Related Art
Flat panel displays such as organic light emitting diode (OLED) displays have an application range that has been rapidly increasing due to their low weight, thinness, low power consumption, good color representation, and high resolution. Currently, usage of the OLED displays is increasing in computers, laptops, phones, TVs, and audio/video devices. The OLED display controls a driving current amount transmitted to an organic light emitting element according to an image data signal or video signal applied to a plurality of pixels arranged in a matrix shape to display an image according to data signals.
Glass substrates may be used as substrates of the display panels. However, these glass substrates act as insulators such that static electricity generated in a panel manufacturing process is charged to the glass substrates. This results in dust, etc., being easily attached thereto, thereby generating process defects. Further, the static electricity may damage elements inside the panel.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the present invention and therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
Aspects of embodiments of the present invention are directed toward a static electricity preventing display panel, a manufacturing method of the static electricity preventing display panel, and a display device including the static electricity preventing display panel. Further aspects relate to a static electricity preventing display panel using a wire to test a mother glass of display panels, a manufacturing method of the static electricity preventing display panel, and a display device including the static electricity preventing display panel.
An exemplary embodiment of the present invention helps prevent erroneous operation of, and damage to, a display panel, and helps prevent a process deterioration of a corresponding display device (incorporating the display panel) due to static electricity by helping to prevent inflow and generation of static electricity in the display panel. In addition, an exemplary embodiment of the present invention provides for a display panel having excellent efficiency in eliminating static electricity in the corresponding display device (incorporating the display panel) by helping prevent static electricity from flowing in through an outermost wire of the display panel remaining after testing a mother glass of the display panels.
In an exemplary embodiment of the present invention, a display panel is provided. The display panel includes: a substrate; a display unit on the substrate and including a plurality of pixels for displaying an image according to a video signal; a power supply wire on the substrate, coupled to the plurality of pixels, and configured to transmit a driving voltage for driving the plurality of pixels; and a dummy wire on the substrate, separated from the display unit and the power supply wire, and coupled to a ground electrode or a power supply unit for supplying the driving voltage.
The dummy wire may be a wire for testing a mother glass including a plurality of display panels including the display panel.
The dummy wire may be coupled to a capacitor that is coupled to the ground electrode or the power supply unit. The capacitor may include one terminal coupled to the dummy wire and another terminal coupled to the ground electrode or the power supply unit.
The dummy wire may be extended to a flexible printed circuit (FPC) including the ground electrode or the power supply.
The substrate may be a flexible substrate. The dummy wire may be extended to the FPC after passing through a film on which is mounted a driver for driving the display unit.
The power supply wire may include a first power supply wire for transmitting a first power source voltage, and a second power supply wire for transmitting a second power source voltage that is lower than the first power source voltage.
The power supply unit may include a first power source voltage supply unit for supplying a first power source voltage of a high potential, and a second power source voltage supply unit for supplying a second power source voltage of a low potential that is lower than the first power source voltage. The dummy wire may be coupled to the second power source voltage supply unit of the power supply unit.
The dummy wire may be located at edges of the substrate.
The dummy wire may be configured to transmit and remove static electricity through the ground electrode or the power supply unit coupled to the dummy wire.
According to another exemplary embodiment of the present invention, a method of manufacturing a display panel is provided. The method includes: manufacturing a mother glass including the display panel and a dummy wire for testing the mother glass; testing the mother glass for defects using the dummy wire; cutting the mother glass into a plurality of display panels including the display panel; coupling a driving circuit for driving a plurality of pixels included in the display panel, the display panel being configured to display an image according to a video signal; grounding the dummy wire included in the display panel or coupling the dummy wire to a power source voltage supply unit for supplying a power source voltage of a low potential; and testing the display panel for defects after the grounding of the dummy wire or the coupling of the dummy wire to the power source voltage supply unit.
The dummy wire may be electrically floated after the cutting of the mother glass.
The power source voltage of the low potential may be a lower voltage than a voltage of static electricity flowing in to the dummy wire.
The dummy wire may be coupled to a capacitor that is coupled to a ground electrode or the power source voltage supply unit.
According to yet another exemplary embodiment of the present invention, a display device is provided. The display device includes: a substrate; a display unit on the substrate and including a plurality of pixels for displaying an image according to a video signal; a power supply wire on the substrate, coupled to the plurality of pixels, and configured to transmit a driving voltage for driving the plurality of pixels; a dummy wire on the substrate, separated from the display unit and the power supply wire, and coupled to a ground electrode or a power supply unit for supplying the driving voltage; and a flexible printed circuit (FPC) including the ground electrode or the power supply unit.
The substrate may be a flexible substrate. The display device may further include a film between the substrate and the FPC on which is mounted a driving circuit for controlling operation of the display unit.
The FPC may further include a bypass capacitor for storing static electricity flowing in to the dummy wire. The bypass capacitor may include one terminal coupled to the dummy wire and another terminal coupled to the ground electrode or the power supply unit.
The power supply wire may include a first power supply wire for transmitting a first power source voltage, and a second power supply wire for transmitting a second power source voltage that is lower than the first power source voltage. The dummy wire may be coupled to the second power supply wire.
The power supply unit may include a second power source voltage supply unit for supplying the second power source voltage to the second power supply wire. The dummy wire may be coupled to the second power source voltage supply unit.
The dummy wire may be a wire for testing a mother glass of a plurality of ones of the display unit, the power supply wire, and the dummy wire.
The dummy wire may be located at edges of the substrate.
According to the above and other embodiments of the present invention, inflow and generation of static electricity to a display panel may be prevented such that erroneous operation of, and damage to, the display panel, and a process defect of a corresponding display device (incorporating the display panel) due to static electricity may be prevented. In addition, static electricity flowing in due to an outermost wire of the display panel remaining after the mother glass test of the display panels may be prevented such that static electricity may be efficiency reduced or eliminated in the display device, and display panels having excellent quality may be provided.
The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Parts not related to the present invention may be omitted for clearer description. Further, like reference numerals designate like elements and similar constituent elements throughout the specification and drawings. Throughout this specification and the claims that follow, when it is described that an element is “coupled” to another element, the element may be “directly coupled” (e.g., connected) to the other element or “indirectly coupled” (e.g., electrically connected) to the other element through one or more third elements. In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.
According to comparative methods of manufacturing display panels, when a mother glass of the display panels is cut after testing the mother glass in the manufacturing process of the display panels, outermost wires for testing the display panels of the mother glass may remain on right and left edges of the panels. As such, outermost wires for testing the display panels of the mother glass may be floated (e.g., electrically floated) after the cutting such that an inflow path of static electricity may be formed close to a power supply wire or a signal wire, which can lead to process defects and damage to elements in the display panels. Accordingly, exemplary embodiments of the present invention provide for the manufacture of display panels that help to prevent erroneous operation and damage to the display panels of OLED displays due to static electricity and, more particularly, that help to help prevent static electricity from flowing in through outer wires used for testing a mother glass of such display panels.
The illustrated display devices of the display panel 1 of
Referring to
A second power supply wire 100 and a dummy wire 200 are formed on the glass substrate of the display panel 1. Integrated circuits (for example a gate driver, a data driver, etc.) for providing driving signals to the display panel 1 may be, for example, provided in the driver 20 or mounted on the FPC 2, thereby transmitting the driving signals to the display panel through the driver 20 or the FPC 2. The kind of FPC or PCB 2 of the present invention is not limited to the above. In other embodiments, it may be, for example, a rigid PCB or a flexible PCB.
Referring to the exemplary embodiment of
The second power supply wire 100 is formed on the glass substrate to enclose an edge portion of the display panel 1. Also, the second power supply wire 100 is coupled to a first common node N1, and a wire extended from the first common node N1 is coupled to the power supply unit 30 formed on the FPC 2. The power supply unit 30 supplies the second power source voltage (ELVSS) of a low level through the second power supply wire 100. The power supply unit 30 supplies the first power source voltage (ELVDD) of a high level through a first power supply wire (see, for example, first power supply wire 13 of
Meanwhile, the dummy wire 200 formed on the glass substrate in
This outermost dummy wire 200 that is provided for an external test (for example, while the display panel 1 is on a mother glass of display panels) may also form a main inflow path of static electricity to the display panel. As such, it is desirable to form a structural and circuit member for preventing generation of static electricity due to the dummy wire 200 in the manufacturing process of the display panel 1 of the display device. Accordingly, referring to
For the exemplary embodiment of
Meanwhile, the mother glass test dummy wire 200 that is formed at the right and left outermost edge portions of the display panel 1 is extended through the chip on film 3 to be coupled to the second common node N2, which is in turn coupled to the ground electrode 40 formed in the FPC 2. The display device of
The display device of
The dummy wire 200 is coupled to a member (for example, a wire or an electrode) for supplying the second power source voltage (ELVSS) of the low level from the power supply unit 30. Although the second power supply wire 100 and the dummy wire 200 are coupled, thereby receiving the second power source voltage of the low level, static electricity transmitted through the dummy wire 200 may be removed by the second power source voltage of the low potential.
For the display device of
That is, the dummy wire 200 of the display panel 1 is coupled to the second common node N2, which is in turn coupled to one terminal of the bypass capacitor 50 formed on the FPC 2. In addition, the other terminal of the bypass capacitor 50 is coupled to the ground electrode 40 formed in the same FPC 2. The bypass capacitor 50 bypasses static electricity that may flow in through the dummy wire 200 from the outside to be temporary stored. Further, in the exemplary embodiment of
For better understanding and ease of description, constituent elements of the display panel 1 may be partially omitted (for example, fewer rows and columns may be depicted in
Referring to
As described in the above exemplary embodiment, the second power supply wire 100 is positioned in the edge portion of the display panel 1 while the display unit including a plurality of pixels is positioned in the center portion of the display panel 1. In addition, the dummy wire 200 is positioned along the right and left edge portions of the display panel 1. The dummy wire 200 used in the mother glass test remains in a floating state after the cell cutting process (which takes place after the mother glass test), as shown in
The first power supply wire 13 is a wire for receiving and transmitting the first power source voltage (ELVDD) of the high potential from the power supply unit 30, and may be formed with a lattice shape in the region of the display unit. The first power supply wire 13 in
The display unit includes subpixels for displaying one of three colors (for example, red, green, and blue) as shown in
After forming the display unit in
Referring to
The plurality of pixels is formed at the crossing regions of the vertical wires and the horizontal wires of the first power supply wire 13 arranged with the lattice shape. For example, the plurality of pixels is arranged as subpixels of the different colors, such as one of the first color subpixels 15-1 (arranged in a row (or column) direction) for displaying a first color, one of the second color subpixels 15-2 (arranged in a row (or column) direction) for displaying a second color, and one of the third color subpixels 15-3 (arranged in a row (or column) direction) for displaying a third color, which are sequentially and repeatedly arranged. Here, the first color may be red, the second color may be green, and the third color may be blue. The pixel arrangement of the colors is not limited thereto, and may differ in other embodiments.
After forming the subpixels, a second power source voltage layer 17 for supplying the second power source voltage is formed on a region corresponding to the display unit and coupled to the second power supply wire 100. The first power source voltage and the second power source voltage for driving the display unit is supplied from the power supply unit (for example, power supply unit 30 in
The first power supply wire 13 transmits the first power source voltage (ELVDD) of the high potential to the pixels, while the second power source wire 100, which is coupled to the second power source voltage supply layer 17, transmits the second power source voltage (ELVSS) of the low potential or the ground potential to the pixels. The display panel 1 includes contact holes 19 to couple each of the plurality of subpixels 15-1, 15-2, and 15-3 of the display unit to the first power supply wire 13. In addition, the display panel 1 includes a connection coupling each of the plurality of subpixels 15-1, 15-2, and 15-3 to the second power source voltage supply layer 17.
Finally, an opposing substrate 16 is formed at an uppermost portion of the display unit region. The opposing substrate 16 may be a glass substrate or other substrate made of a transparent material. In the display panel of
The display panel 1 according to embodiments of the present invention has a structure that removes static electricity by using a dummy wire. In
Next, a process of testing the mother glass for defects is performed (S2). In the mother glass test, the mother glass is coupled through the dummy wire to test the quality and/or performance of the mother glass. If the mother glass is defective, it is repaired through a repairing process if possible, or the mother glass is disposed of as a faulty product if the repairing is impossible. The tested mother glass that is repaired (if needed) and that is determined to be a good product then undergoes a display panel (cell) process (S3). The panel (cell) process includes a process of finishing OLEDs (such as completely forming or further forming the OLEDs), and a cell cutting process of cutting the mother glass into units in which the dummy wire is floated. In the display panel process, the panel test process may be performed as a cell unit.
Next, a module process (S4) is performed. The module process is a process of coupling the driving circuit for driving the display panel that is determined to be a good product (after the panel test) or is repaired (when possible). For example, the power supply unit formed in the flexible printed circuit (FPC), other films, and/or the driver mounted on the substrate are coupled to the display panel.
The connection of the dummy wire that is floated in the cell cutting process (of the cell process S3) is then coupled to the ground electrode on the FPC or to the power source voltage supply unit for supplying the second power source voltage of the low potential (S5). The low potential power source voltage should be a lower voltage than the static electricity voltage applied through the floated dummy wire. Thus, static electricity that may flow in from the outside through the floated dummy wire may be removed through the ground electrode or the power source voltage supply unit for supplying the second power source voltage of the low potential.
If the process of the circuit connection for preventing static electricity is finished, a final test of the display panel is performed (S6). In the final test, if the display panel is determined to be a good product, the manufacturing of the display panel is completed (S7).
The drawings and detailed description described above represent exemplary embodiments of the present invention and are provided to better explain aspects and principles of the present invention. However, the scope of the present invention described above is not limited thereto. It will be appreciated by those skilled in the art that various modifications may be made and that other equivalent embodiments are available, all within the spirit and scope of the present invention. In addition, some of the components described in the specification may be omitted without deterioration of performance, or added in order to improve the performance, as would be apparent to those skilled in the art. Moreover, the sequence of steps of the methods described in the specification may be changed depending on a process environment or equipment as would be apparent to those skilled in the art. Accordingly, the spirit and scope of the present invention should be not limited by the above-mentioned exemplary embodiments, but by the appended claims and equivalents thereto.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2012-0071792 | Jul 2012 | KR | national |
