1. Field of the Invention
The present invention relates to a light transmission touch panel, and more particularly, to a touch panel having capacitance circuits.
2. Description of the Related Art
Touch panels have been widely applied in the fields of household appliances, communications, and electronic information devices. Common applications of the touch panel include input interfaces of personal digital assistants (PDA), electrical appliances, game machines, and other devices.
The current trend of integration of touch panel and display panel allows a user to use his or her finger or a stylus to indicate a control icon shown on the panel in order to execute a desired function on the device. The touch panel is also applied in public information inquiry systems to provide an is efficient operation system for the public.
A conventional touch panel comprises a transparent substrate having a surface on which sensing zones are distributed for sensing a signal associated with the touch of a user's finger or stylus to effect input and control. The sensing zones are made of transparent conductive membranes, such as indium tin oxide (ITO), and a user may touch the transparent conductive membrane corresponding to a specific location shown on the display to effect operation of the device.
In order to detect the location where a finger or a stylus touches the touch panel, a variety of capacitive touch panel techniques are developed. As shown in
The prior art first electrodes 141 and second electrodes 142 are square or diamond transparent electrodes. However, the transparent electrodes absorb some amount of light, which causes the touch panel 10 to absorb too is much light emitted from a lower display apparatus (not shown). Therefore, the touch screen appears darker.
Thus, there is a need to provide a touch panel that overcomes the above drawbacks of the conventional touch panels, and still has good electrical characteristics.
An aspect of the present invention is to provide a capacitive type touch panel with high transmittance. The pattern of the sensing electrode of the capacitive type touch panel is a wiring pattern rather than a conventional square or diamond pattern, and thus the light absorbed by the sensing electrode can be reduced while maintaining the same surrounding area or effective sensing area of the wiring pattern.
Another aspect of the present invention is to provide a capacitive type touch panel with lower resistance. A plurality of auxiliary metal lines are disposed on the connecting lines which connect electrode units, and on the wiring pattern of the sensing electrode. Since the auxiliary metal lines can support large currents, the connecting lines or wiring electrodes having higher resistance can be protected, and the overall impedance of the sensing conductive layer can be reduced.
In view of above, the present invention discloses a capacitive type touch panel which comprises a transparent substrate, a transparent conductive layer, an insulating layer, and a plurality of first leads. The transparent conductive layer is overlaid on a surface of the transparent substrate and comprises a plurality of first electrodes, a plurality of second electrodes and a plurality of connecting lines. The plurality of first electrodes and the plurality of second electrodes are arranged in a staggered manner, and the plurality of connecting lines respectively connect two adjacent second electrodes. The insulating layer comprises a plurality of insulating areas, wherein the plurality of insulating areas are respectively overlaid on the plurality of connecting lines. The plurality of first leads are is respectively disposed on the plurality of insulating areas and respectively connect two adjacent first electrodes. Each of the first electrodes and second electrodes has a pattern which is formed by transparent electrode leads.
The capacitive type touch panel further comprises a plurality of second leads respectively disposed on each of the transparent electrode leads.
The present invention further discloses a capacitive type touch panel which comprises a first transparent substrate, a first transparent conductive layer, a second transparent substrate, and a second transparent conductive layer. The first transparent conductive layer is overlaid on a surface of the first transparent substrate and comprises a plurality of first electrodes and a plurality of first connecting lines, wherein the plurality of first connecting lines respectively connect the adjacent first electrodes. The second transparent substrate is disposed on the first transparent conductive layer. The second transparent conductive layer is disposed on the second transparent substrate and comprises a plurality of second electrodes and a plurality of second connecting lines, wherein the plurality of second connecting lines respectively connect the adjacent second electrodes. Each of the first electrodes and second electrodes has a wiring pattern which is formed by transparent electrode leads.
The invention will be described according to the appended drawings in which:
Because the transparent connecting lines 243 and the transparent electrode leads 244 have higher resistances, a plurality of second leads 245 can be respectively disposed on the connecting lines 243 and the electrode leads 244. In this manner, the transparent connecting lines 243 and the transparent electrode leads 244 having higher resistances can be protected, and the overall impedance of the transparent conductive layer 24 can be reduced. The second leads 245 and the first leads 22 are preferably formed is by the same photolithography process, or by another photolithography process. To avoid oxidation or scratching on the second leads 245 and first leads 22, a passivation layer (not shown) can be overlaid on the second leads 245 and/or first leads 22.
The material of the transparent conductive layer 24 is an indium-tin oxide (ITO), aluminum-zinc oxide (AZO) or indium-zinc oxide (IZO). The photolithography processes include sputter, coating, exposure, soft baking, hard baking, development, baking and other processes. The material of the transparent substrate 21 is glass or a transparent polymer plate such as polycarbonate (PC) and polyvinyl chloride (PVC). The material of the insulating layer 23 is a transparent polymer such as a photoresist material. The material of the first leads 22 and second leads 245 is polymer conductive material, conductive oxide or metal.
The first transparent conductive layer 32 can be formed on the first transparent substrate 31 first. Also, the second transparent conductive layer 34 can be formed on the second transparent substrate 33 first, and then the first transparent substrate 31 having circuits can be combined, for example by adhesion, with the second transparent substrate 33 having circuits.
The first electrode 421 in
Referring to
The first electrodes 321, the first dummy electrodes 322, the second electrodes 341, and the second dummy electrodes 342 of the present invention have a pattern formed by transparent electrode leads. The pattern can be, but not limited to, a closed wiring, an open wiring, a meandering or zig-zag straight line, a meandering or zig-zag curved line, a mesh wiring, and a groove wiring.
The above descriptions of the present invention are intended to be illustrative only. Numerous alternative methods may be devised by persons skilled in the art without departing from the scope of the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 098124672 | Jul 2009 | TW | national |