Patent Application
20120044182
This application claims the benefit of Korean Patent Application No. 10-2010-0080984, filed on Aug. 20, 2010, which is hereby incorporated by reference for all purposes in its entirety.
1. Field of the Invention
This specification relates to a touch panel and a flat panel display device having the same, and particularly, to a touch panel with high transmittance, capable of implementing a high-resolution screen upon driving a flat panel display device having the touch panel, and a flat panel display device having the same.
2. Background of the Invention
A display device is a visual information transfer medium, which visually displays data on a cathode ray tube (CRT) screen in form of characters or figures.
In general, a flat panel display (FPD) device is an image display device, which is thin in thickness and light in weight, and there are various types of FPD devices, such as a liquid crystal display (LCD) using liquid crystal, a plasma display panel (PDP) using gas discharging, an organic light emitting diode (OLED) display using a fluorescent organic compound which emits light when a current flows on the compound.
Meanwhile, a touch panel, which is aligned on the FPD device and can be pressed by a user with a finger or a pen to input a corresponding command, has been developed.
The touch panel is already being widely applied, starting from automated teller machines (ATM) of banks to portable information devices, such as portable digital assistants (PDA), notebook computers, tablet PCs and the like. In general, the LCD is most frequently used as the FPD device to be attached onto the touch panel.
The touch panels may be categorized according to a method for detecting a touch depending on a resistive type, a capacitive type, an electromagnetic type and the like.
Among the various types of touch panels, the capacitive type touch panel is configured such that when a finger or a conductor such as a pen is located in the vicinity of an upper glass substrate or touches the substrate, a voltage drop is generated and thus the touch position is detected by the change in the voltage.
The capacitive type touch panel has no air layer in the middle, unlike the resistive type touch panel, and is able to remarkably suppress reflectivity generated at an interface. Also, the capacitive type touch panel has a structure, in which interference non-uniformity (Newton ring) or glittering is rarely caused, resulting in high optical properties.
Referring to
An insulating layer 50 is formed on the lower electrodes 30. Here, the insulating layer 50 is interposed between the lower electrodes 30 and upper electrodes 70 for insulation therebetween.
First and second contact holes 53 and 55 are formed through the insulating layer 50 to partially expose the lower electrodes 30. The upper electrodes 70 are formed on the insulating layer 50. Here, the lower electrodes 30 and the upper electrodes 70 are electrically connected to each other via the first and second contact holes 53 and 55.
Here, the upper electrode 70 may be provided in plurality, and each includes a first upper electrode 72 and a second upper electrode 76. The first upper electrode 72 is formed in a lozenge-shaped pattern. The lozenge-shaped first upper electrodes 72 of the upper electrodes 70 are connected together by upper connecting portions 74, which are provided for connection among the lozenge-shaped first upper electrodes 72. On the other hand, the second upper electrodes 76 of the upper electrodes 70 are also formed in the same lozenge-shaped patterns as the first upper electrodes 72, but spaced apart from one another by preset intervals.
Here, the lower electrode 30 and the upper electrode 70 may be formed of a conductive polymer, such as indium tin oxide (ITO), which is transparent and conductive or a metal.
Referring to
As shown in
Therefore, to address such problems of a capacitive type touch panel described above, one aspect of the detailed description is to provide a touch panel, which is allowed to have high transmittance by forming lower electrodes, each having a preset inclination and capable of implementing a high-resolution screen upon driving a flat panel display device having the touch panel, and a flat panel display device having the same.
To achieve these and other advantages and in accordance with the purpose according to one aspect of the invention, as embodied and broadly described herein, a touch panel may include an insulating substrate, a plurality of lower electrodes formed on the substrate, each of the lower electrodes having a preset inclination, an insulating layer formed on the lower electrodes and having a plurality of contact holes for partially exposing the plurality of lower electrodes, a plurality of upper electrodes formed on the insulating layer and electrically connected to the plurality of lower electrodes via the plurality of contact holes, and a passivation layer formed on the upper electrodes.
In some embodiments, the lower electrodes may be spaced apart from one another with preset intervals.
In further embodiments, the upper electrodes may include first upper electrodes, each having a lozenge-shaped pattern and connected to one another by connecting portions, and second upper electrodes, each having a lozenge-shaped pattern and present between the connecting portions, where the second upper electrodes are spaced apart with preset intervals.
In yet further embodiments, the interval between the second upper electrodes may be in the range of 50 μm to 90 μm.
In additional embodiments, the interval between the connecting portion of the first upper electrode and the second upper electrode may be in the range of 8 μm to 12 μm. The width of the connecting portion may be in the range of 40 μm to 60 μm. The inclination of the lower electrode may be in the range of 5° to 40°. The length of the lower electrode may be in the range of 120 μm to 560 μm. The width of the lower electrode may be in the range of 3 μm to 5 μm.
In yet additional embodiments, the inclination of the lower electrode may differ depending on resolution of a flat panel display device. The number of lower electrodes may differ depending on the resolution of the flat panel display device and/or on the number of channels in the touch panel chip (IC) of Flexible Printed Circuit (FPC).
In accordance with one exemplary embodiment, a flat panel display device may include a touch panel described herein.
In accordance with another exemplary embodiment, a flat panel display device may include a touch panel including a plurality of lower electrodes formed on an insulating substrate, each of the lower electrodes having a preset inclination, an insulating layer formed on the lower electrodes and having a plurality of contact holes for partially exposing the plurality of lower electrodes, a plurality of upper electrodes formed on the insulating layer and electrically connected to the plurality of lower electrodes via the plurality of contact holes, and a passivation layer formed on the upper electrodes, an organic light emitting diode layer located below the touch panel, an array substrate located below the organic light emitting diode layer, and a polarizer for organic light emitting diode located on the touch panel.
In additional embodiments, the polarizer for organic light emitting diode may include a phase delay film. The pixels formed on the array substrate may be smaller than the lower electrodes.
As described above, in accordance with the touch panel and the flat panel display device, each of lower electrodes on the touch panel can have a preset inclination, thereby fabricating a touch panel having high transmittance, and also a high-resolution screen can be implemented upon driving the flat panel display device having the touch panel.
Further scope of applicability of the present application will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from the detailed description.
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 exemplary embodiments and together with the description serve to explain the principles of the invention. In the drawings:
Description will now be given in detail of a touch panel and a flat panel display (FPD) device having the same according to the exemplary embodiments, with reference to the accompanying drawings. For the sake of brief description with reference to the drawings, the same or equivalent components will be provided with the same reference numbers, and description thereof will not be repeated.
Referring to
Referring to
In some embodiments, the lower electrode 230 and the upper electrode 270 may be formed of a conductive polymer, such as indium tin oxide (ITO), which is transparent and conductive.
Referring to
In some embodiments, the inclination of the lower electrode 230 may be in any range or in the range of 5° to 40°. The inclination of the lower electrode 230 may differ depending on resolution of the FPD device. Also, a length L11 of the lower electrode 230 may be, for example, in the range of 120 μm to 600 μm, and a width W11 of the lower electrode 230 may be as narrow as possible as further described below.
When the lower electrodes 230 are formed in a horizontal direction, upon driving the FPD device having the touch panel, the lower electrodes 230 may overlap part of pixels to thereby make shadows, which are visible to the naked eyes, thereby lowering the transmittance of the touch panel. Hence, to address the problem, the lower electrodes 230 having the structure described herein is proposed.
On the other hand, in the case where the lower electrodes (Width W11 13 μm; Length L11 128 μm) were angled at 23°, the shadows were not visible with naked eyes. Also, in the case where the lower electrodes (Width W11 18 μm; Length L11 560 μm) were angled at 15°, the shadows again were not visible. Accordingly, the angled lower electrodes removed the shadows of the lower electrodes and thus improves the transmittance of the touch panel. Consequently, when an FPD device having such a touch panel with the angled lower electrodes is in operation, the quality of the screen is improved.
Referring to
In some embodiments, based on the width and length of contact holes to be formed later, the width W11 of the lower electrode 230 may be in the range of 12 μm to 18 μm, for example.
Referring to
In some embodiments, a width W12 of the upper connecting portion 274 of the first upper electrode 272 may be in the range of 40 μm to 60 μm, for example. An interval D11 between the upper connecting portion 274 of the first upper electrode 272 and the second upper electrode 276 may be in the range of 8 μm to 12 μm, for example. Also, an interval D12 between the second upper electrodes 276 may be in the range of 50 μm to 90 μm, for example. μm
As described herein, the previous embodiment has exemplarily illustrated that the two contact holes are formed through the insulating layer 250 for an electric connection between the lower electrode 230 and the corresponding upper electrode 270. Alternatively, two or more contact holes may be formed through the insulating layer 250 to improve a signal transfer capability according to the resolution of the FPD device.
One exemplary embodiment has illustrated above that the lower electrode 230 is first formed on the substrate 210 and then the upper electrode 270 is formed on the insulating layer 250. Alternatively, it is also possible that the upper electrode 270 is first formed on the substrate 210 and the lower electrode 230 is formed on the insulating layer 250.
In some embodiments, as shown in
In additional embodiments, the hole transport layer 420 and the electron transport layer 440 may have properties that electricity flows thereon when a high voltage is applied, and these layers may be made of a photosensitive material. The hole transport layer 420 may be made of a material including, for example, TPD, NPD, TPAC and the like. The electron transport layer 440 may be made of a material including, for example, BND, PBD, BCP and the like. In further embodiments, the light emitting layer 430 may render various colors according to luminous materials. The entire light emitting layer 430 may be made of a material having the same color. Alternatively, a part of the light emitting layer 430 may be made of a material with a different color.
In yet additional embodiments, the OLED layer 400 may have the structure of a passive matrix OLED (PMOLED).
Although not shown, an LCD (not shown) for displaying images may be disposed, for example, below the touch panel 200. In some embodiments, the LCD may include an liquid crystal (LC) panel provided with a thin film transistor (TFT) array substrate having switching devices, a color filter substrate having color filters, and an LC layer interposed between the TFT array substrate and the color filter substrate, and a backlight unit for emitting light to the LC panel.
In further embodiments, the backlight unit may include a reflection plate for guiding light emitted from a light source to a light-guiding plate and minimizing the loss of light emitted from the light source, a light-guiding plate for converting incident light from the light source into a surface light source and guiding the converted surface light source to the LC panel, optical sheets attached on the light-guiding plate, having one or more diffusion sheets and one or more prism sheets, and configured to allow incident light from a surface of the light-guiding plate to be diffused and uniformly radiated on the entire LC panel, and a light source for emitting light to the LC panel by receiving power from an external power source.
As such, in accordance with one exemplary embodiment, each lower electrode 230 is formed to have an inclination, as shown in
In addition, in one exemplary embodiment, as shown in
One exemplary embodiment has illustrated the lower electrodes formed in the horizontal direction. The present disclosure, however, is not limited thereto, and is also applicable to lower electrodes formed in the vertical direction.
The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.
As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2010-0080984 | Aug 2010 | KR | national |
