a. Field of the Invention
The invention relates to a touch-sensing electrode structure and a touch-sensitive device.
b. Description of the Related Art
Nowadays, a touch-sensing electrode structure of a capacitive touch-sensitive device is often fabricated using double-sided ITO or single-sided ITO fabrication processes. On forming conventional double-sided ITO patterns, coating, etching, and photolithography processes are performed on each of a top side and a bottom side of a glass substrate to form X-axis and Y-axis sensing electrodes on the two sides. However, except for being complicated, such fabrication processes may cause low production yields because of the step of flipping over the glass substrate to achieve double-sided patterning. In comparison, on forming conventional single-sided ITO patterns, since X-axis and Y-axis sensing electrodes are formed on the same side of a glass substrate, a bridge wiring structure needs to be formed in a touch screen area. In that case, unstable material characteristics of an organic insulation layer or other factors may cause short-circuit or open-circuit of the X-axis and Y-axis sensing electrodes. Therefore, a single-layer electrode structure is proposed to resolve above problems, where X-axis and Y-axis sensing electrodes are formed in the same layer to simplify fabrication process, increase production yields and reduce fabrication costs. However, in a single-layer electrode structure, an improved electrode layout is needed to achieve better characteristics of touch-sensing controls, such as sufficient coupling-capacitance variations and fine linearity of electric fields. Further, the amount of channels needed for a single-layer electrode structure is very large, and this may result in excessively large bonding areas formed by X-axis and Y-axis sensing electrodes on a flexible printed circuit board and cause high line impedance.
The invention provides a touch-sensing electrode structure and a touch-sensitive device having low line impedance and improved sensitivity and linearity for touch-sensing controls.
According to one embodiment of the invention, a touch-sensing electrode structure includes multiple first electrodes and multiple second electrodes. Each first electrode includes a longitudinal part extending in a first direction and multiple branch parts connected to the longitudinal part. The second electrodes are disposed on at least one side of each longitudinal part, and each of the second electrodes at least spreads over a region between two adjacent branch parts of each of the first electrodes.
In one embodiment, the branch parts of one of the first electrodes have different widths measured in a second direction different to the first direction. The widths of the branch parts of the first electrode may decrease progressively in a direction away from the longitudinal part of the first electrode.
In one embodiment, the branch parts of one of the first electrodes make different angles with the longitudinal part of the first electrode.
In one embodiment, at least two of the second electrodes are disposed symmetrically on two sides of the longitudinal part. Each of the second electrodes includes a plurality of branch parts, and the branch parts of the second electrode are adjacent to the longitudinal part or the branch parts of the first electrode. The branch parts of one of the second electrodes have different widths measured in a second direction different to the first direction. The widths of the branch parts of the second electrode may decrease progressively in a direction away from the longitudinal part of the first electrode.
In one embodiment, each of the first electrodes is a signal-transmitting electrode, and each of the second electrodes is a signal-sensing electrode.
In one embodiment, each of the branch parts of the first electrode is in the form of a first block, each of the second electrodes is in the form of a second block, the touch-sensing electrode structure has multiple first blocks and multiple second blocks, and the first blocks and the second blocks are alternately arranged on each of two opposed sides of the longitudinal part. The first blocks and the second blocks may form a delta topological electrode layout.
In one embodiment, each of the first blocks is partitioned by the second electrode to form a plurality of first regions, and the first regions of the same first block have mutually different widths measured in a second direction substantially perpendicular to the first direction.
In one embodiment, each of the second blocks is partitioned by the first electrode to form a plurality of second regions, and the second regions of the same second block have mutually different widths measured in a second direction substantially perpendicular to the first direction.
According to another embodiment of the invention, a touch-sensitive device includes a substrate, a touch-sensing electrode structure, a plurality of conductive wires, and a flexible printed circuit board. The touch-sensing electrode structure is disposed on the substrate and has a plurality of first electrodes and second electrodes. The touch-sensing electrode structure is partitioned to form a plurality of blocks adjacent to each other, and each of the blocks has at least one first electrode and a plurality of second electrodes. Each of the conductive wires is connected to one of the first electrodes or one of the second electrodes. The flexible printed circuit board is electrically connected to the touch-sensing electrode structure. The first electrode and the plurality of second electrodes in the same block are connected to the flexible printed circuit board through the conductive wires to form a bonding area on the flexible printed circuit board, the flexible printed circuit board is provided with a plurality of bonding areas, and two adjacent bonding areas on the flexible printed circuit board are situated at different distances from the substrate.
In one embodiment, the touch-sensitive device further includes a plurality of grounding wires, and each of the grounding wires is disposed on a boundary between the two adjacent bonding areas.
In one embodiment, a plurality of bonding pads are disposed in each of the bonding areas.
In one embodiment, a plurality of bus lines are disposed on the flexible printed circuit board. The second electrodes are divided into multiple electrode groups, each electrode group is formed by the second electrodes collected from each of the blocks, and the conductive wires connected to the second electrodes in the same electrode group are all connected to the same bus line. The bus lines may be made of metal.
In one embodiment, a decorative layer is disposed on a periphery of the substrate, and the decorative layer may include at least one of ceramic, diamond-like carbon, colored ink, photo resist and resin.
In one embodiment, a passivation layer is disposed on the substrate and covering the touch-sensing electrode structure. The passivation layer may be a refractive-index matching layer.
According to another embodiments of the invention, a touch-sensing electrode structure includes a plurality of first electrodes and a plurality of second electrodes. Each of the electrodes has a major part extending in a first direction and a plurality of branch parts connected to the major part. The second electrodes are disposed on at least one side of each major part, and each of the second electrodes at least spreads over a region between two adjacent branch parts of each of the first electrodes. The branch parts of one of the first electrodes have different widths measured in a second direction different to the first direction.
According to the above embodiments, since multiple sides of the second electrode are adjacent to a longitudinal part or branch parts of the first electrode, the intensity of an electric field formed between the first electrode and the second electrode is increased to increase the amount of coupling capacitance and the sensitivity of touch-sensing controls for a touch-sensing electrode structure. Further, different regions of the first electrode or the second electrode may have mutually different widths to increase the linearity of touch-sensing controls. Besides, two adjacent bonding areas on a flexible printed circuit board may be situated at different distances from a substrate to decrease an entire occupied space of the bonding areas, and the conductive wires connected to the same electrode group are all connected to the same bus line to reduce the amount of channels and line impedance for a single-layer touch-sensing structure.
Other objectives, features and advantages of the invention will be further understood from the further technological features disclosed by the embodiments of the invention wherein there are shown and described preferred embodiments of this invention, simply by way of illustration of modes best suited to carry out the invention.
In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which are shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” etc., is used with reference to the orientation of the Figure(s) being described. The components of the invention can be positioned in a number of different orientations. As such, the directional terminology is used for purposes of illustration and is in no way limiting. On the other hand, the drawings are only schematic and the sizes of components may be exaggerated for clarity. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. Similarly, the terms “facing,” “faces” and variations thereof herein are used broadly and encompass direct and indirect facing, and “adjacent to” and variations thereof herein are used broadly and encompass directly and indirectly “adjacent to”. Therefore, the description of “A” component facing “B” component herein may contain the situations that “A” component directly faces “B” component or one or more additional components are between “A” component and “B” component. Also, the description of “A” component “adjacent to” “B” component herein may contain the situations that “A” component is directly “adjacent to” “B” component or one or more additional components are between “A” component and “B” component. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.
According to an embodiment of the invention, the touch-sensing electrode structure 20 is a single-layer electrode structure.
According to the above embodiments of the invention, included angles formed between the branch parts 222 and the longitudinal part 221 of the first electrode 22 are not limited and may include different values. For example, as shown in
As shown in
It should be noted that the relative positions of aforementioned longitudinal parts and branch parts exemplified in the drawings are not to be construed as limiting the scope of the invention. Any electrode pattern that can be identified to have a major part and at least one branch part subordinate to the major part is within the scope of the present invention.
In an alternate embodiment, multiple second electrodes 24 may be divided into multiple electrode groups, and each electrode group is formed by the second electrodes collected from each of the blocks A1-A3. For example, as shown in
According to the above embodiments, since multiple sides of the second electrode are adjacent to a longitudinal part or branch parts of the first electrode, the intensity of an electric field formed between the first electrode and the second electrode is increased to increase the amount of coupling capacitance and the sensitivity of touch-sensing controls for a touch-sensing electrode structure. Further, different regions of the first electrode or the second electrode may have mutually different widths to increase the linearity of touch-sensing controls. Besides, two adjacent bonding areas on a flexible printed circuit board may be situated at different distances from a substrate to decrease an entire occupied space of the bonding areas, and the conductive wires connected to the same electrode group are all connected to the same bus line to reduce the amount of channels and line impedance for a single-layer touch-sensing structure.
The foregoing description of the preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form or to exemplary embodiments disclosed. Accordingly, the foregoing description should be regarded as illustrative rather than restrictive. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. The embodiments are chosen and described in order to best explain the principles of the invention and its best mode practical application, thereby to enable persons skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use or implementation contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Therefore, the term “the invention”, “the present invention” or the like does not necessarily limit the claim scope to a specific embodiment, and the reference to particularly preferred exemplary embodiments of the invention does not imply a limitation on the invention, and no such limitation is to be inferred. The invention is limited only by the spirit and scope of the appended claims. The abstract of the disclosure is provided to comply with the rules requiring an abstract, which will allow a searcher to quickly ascertain the subject matter of the technical disclosure of any patent issued from this disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Any advantages and benefits described may not apply to all embodiments of the invention. It should be appreciated that variations may be made in the embodiments described by persons skilled in the art without departing from the scope of the invention as defined by the following claims. Moreover, no element and component in the present disclosure is intended to be dedicated to the public regardless of whether the element or component is explicitly recited in the following claims. Each of the terms “first” and “second” is only a nomenclature used to modify its corresponding element. These terms are not used to set up the upper limit or lower limit of the number of elements.
Number | Date | Country | Kind |
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101130198 | Aug 2012 | TW | national |