Patent Application
20100231549
The present invention relates to a liquid crystal display integrated with a touch device. More specifically, it relates to a liquid crystal display integrated with a capacitive touch device.
Liquid crystal displays (LCD) with various designs are commonly used by people. Please refer to
The liquid crystal display module 10 includes a lower polarizing plate 12, a lower substrate 101, a lower conductive layer 102, a liquid crystal layer 103, an upper conductive layer 104, a color filter 13, an upper substrate 105 and an upper polarizing plate 14.
The industry has developed certain technologies for the integration of liquid crystal display panel and touch device, which can make the operation easier. In early stage, the touch device comprises resistance films. When an object touches the surface of the touch device, a stress generated by the object brings the two resistance films into physical contact, so that a switch is turned on and a touch signal is sent to a controller for processing to determine the touched position. However, after long-term usage, the resistance films are prone to damages caused by frequent pressing and it becomes hard to precisely determine the touched position.
In order to overcome the above mentioned defects of the designs that utilized resistance films, a capacitive touch device has developed. A capacitive touch device comprises two touch sensing layers and a medium layer arranged between the two touch sensing layers. In conventional manufacturing processes, the liquid crystal display panel and the capacitive touch device are produced separately, and then subsequently stacked and attached together. A user can use a conductive object such as a finger or stylus to select the icons shown on the surface of the touch device to operate or to input data.
However, it is required to separately attach a protective layer to the surface of the touch device and that of the liquid crystal display panels. The protective layers are primarily made of glass. As a result, the use of two protective layers requires the consumption of a large amount of materials for manufacturing. In addition, as described above, touch devices and liquid crystal displays are separately manufactured, and then subsequently stacked and adhered together. Such an assembly process is complicated and time consuming, and also tends to produce defective products. Moreover, the products manufactured in this way will inherently have a greater thickness, which makes it difficult to further slim down the whole device.
It is an object of the present invention to provide a liquid crystal display with an integrated capacitive touch device that does not require additional substrates. In this way, further reduction in device thickness can be achieved.
The liquid crystal display of the present invention, in one embodiment, comprises a liquid crystal display panel, a first electrode layer and a second electrode layer. The liquid crystal display panel comprises a liquid crystal display module comprising an upper polarizing plate and a lower polarizing plate. The first electrode layer comprises an electrode pattern (e.g., a predetermined electrode pattern) formed on a surface, such as the top surface, of the upper polarizing plate. The second electrode layer comprises an electrode pattern formed on the bottom of the upper polarizing plate.
In another embodiment, a liquid crystal display and a capacitive touch sensing layer that is capable of sensing touch movement in a first and a second direction, such as X-axis movement and Y-axis movement, are included. The capacitive touch sensing layer is formed immediately on a surface, such as the top or bottom surface, of the upper polarizing plate.
By means of the present invention, a liquid crystal display as described can be integrated with a capacitive touch device without using extra substrates. The present invention enables an integrated capacitive touch device be made slimmer and lighter. More particularly, the liquid crystal display is directly integrated with capacitive touch device in a simpler manufacturing process instead of being assembled together after separate manufacturing processes. It has many advantages such as a simpler manufacturing process, a higher yield rate, and a lower manufacture cost. In addition, because the electrode layer is attached, e.g., to the top of the upper polarizing plate of the liquid crystal display and is closer to the finger or other touch object, the electrode layer's touch-sensing ability is improved.
Please refer to
The liquid crystal display panel 1 comprises a lower polarizing plate 12, a lower substrate 101, a lower conductive layer 102, a liquid crystal layer 103, an upper conductive layer 104, a color filter 13, an upper substrate 105, an upper polarizing plate 14 and a protective layer 11. The color filter 13 includes a black matrix and a color resist.
The first electrode layer 2 is formed immediately on top of the upper polarizing plate 14; and the second electrode layer 3 is formed immediately on the bottom of the upper polarizing plate 14.
According to the first embodiment, the electrode strips 21 of the first electrode layer 2 are arranged in a direction substantially perpendicular to that of the electrode strips 31 of the second electrode layer 3. The electrode strips 21 of the first electrode layer 2 is configured to sense a touch movement in a first direction, such as axis Y, and the electrode strips 31 of the second electrode layer 3 is configured to sense a touch movement in a second direction, such as axis X. It is apparent that the electrode strips 21 of the first electrode layer 2 can be configured to sense a touch movement in axis X, and the electrode strips 31 of the second electrode layer 3 is configured to sense a touch movement in axis Y.
The electrode strips 21 and 31 can have different shapes. For example, the electrode strips can have shapes of diamond, square, or hexagon. As shown in
The first electrode layer 2 and the second electrode layer 3 of the liquid crystal display are electrically coupled with the controller (not shown in figure). When a user touches the liquid crystal display (e.g., direct contact with a finger or indirect contact via a conductive object), the object is separately and capacitively coupled to the first electrode layer 2 and the second electrode layer 3, so that, e.g., a touch signal corresponding to the X-axis coordinate and Y-axis coordinate of the touched position is generated and the signal is sent to the controller for further processing to determine the touched position.
Please refer to
The capacitive touch sensing layer 4 comprises an electrode pattern 40, which comprises a plurality of first electrode strips 41 and second electrode strips 42. The first electrode strips 41 are arranged in a direction substantially perpendicular to that of the second electrode strips 42. The second electrode strips 42 overlap on the first electrode strips 41, but the first and second electrode strips are not in direct physical contact. An insulating layer 43 is formed on the first electrode strips 41 at where the second electrode strips 42 overlap the first electrode strips 41 (as shown in
When a user touches a capacitive touch device as described in the present invention with an object (e.g., a finger or a conductive object), the object is separately and capacitively coupled to the first electrode 41 and the second electrode 42, so that a touch signal according to the touched area size and corresponding to the X-axis and Y-axis coordinate of touched position is generated and sent to the controller for further signal processing to determine the touched position (not shown in diagram).
Although the present invention has been described with reference to the embodiments thereof and the best modes for carrying out the present invention, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention, which is intended to be defined by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 098108169 | Mar 2009 | TW | national |
