This application claims priority of Taiwanese Application No. 099201763, filed on Jan. 28, 2010.
1. Field of the Invention
The invention relates to a touch module, and more particularly to a capacitive touch module.
2. Description of the Related Art
Referring to
It is noted that the ribbon cable 18 has a thickness of about 100 μm, whereas the insulating layer 17 has a thickness less than 25 μm. When inserting the ribbon cable 18 between the first and second substrates 11, 12, the second substrate 12 buckles at the edge thereof, and the first conductive traces 16 may be broken as a result of edge buckling of the second substrate 12 such that production yield is adversely affected. In addition, each terminal 181 of the ribbon cable 18 should be exactly aligned with the corresponding one of the first and second conductive traces 15, 16 when inserting the ribbon cable 18 between the first and second substrates 11, 12, thereby resulting in relatively complicated assembly.
Furthermore, when the conventional capacitive touch module is applied to a handheld electronic device with a small size, the ribbon cable 18 is usually disposed adjacent to internal circuits of the electronic device. As a result, analog signals transmitted by the ribbon cable 18 are easily interfered, thereby resulting in misoperation of the control circuit 19.
Therefore, an object of the present invention is to provide a touch module that can overcome the aforesaid disadvantages of the prior art.
According to the present invention, a touch module comprises:
a first substrate having a first surface;
a second substrate opposite to the first substrate and having a second surface that faces the first surface of the first substrate;
a trace unit formed on the first surface of the first substrate, and including a plurality of first conductive traces and a plurality of second conductive traces, each of the first and second conductive traces having an end portion covered by the second substrate;
a sensing unit disposed between the first surface of the first substrate and the second surface of the second substrate, and connected electrically to the end portions of the first and second conductive traces of the trace unit, the sensing unit being operable to generate a sensing output in response to touching on or approaching the first substrate by a conductive object; and
a control circuit unit disposed on the first surface of the first substrate, exposed from the second substrate, and coupled to the first and second conductive traces of the trace unit such that the control circuit unit receives the sensing output generated by the sensing unit through the first and second conductive traces of the trace unit, the control circuit unit being operable to generate a control output based on the sensing output received thereby.
Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, of which:
Before the present invention is described in greater detail, it should be noted that like elements are denoted by the same reference numerals throughout the disclosure.
Referring to
The first substrate 2 has a first surface 21. The second substrate 3 is opposite to the first substrate 2, and has a second surface 31 that faces the first surface 21 of the first substrate 2. In this embodiment, each of the first and second substrates 2, 3 is made from a transparent material. When the touch module 100 is applied to an electronic device (not shown), one of the first and second substrates 2, 3 can serve as a housing part of the electronic device.
The trace unit 5 is formed on the first surface 21 of the first substrate 2, and includes a plurality of first conductive traces 51 and a plurality of second conductive traces 52. Each of the first and second conductive traces 51, 52 has an end portion 511, 521 covered by the second substrate 3. In this embodiment, each of the first and second conductive traces 51, 52 is made from a transparent conductive material, such as indium tin oxide (ITO) or zinc oxide (ZnO).
The sensing unit 4 is disposed between the first surface 21 of the first substrate 2 and the second surface 31 of the second substrate 3, and is connected electrically to the end portions 511, 521 of the first and second conductive traces 51, 52 of the trace unit 5. The sensing unit 4 is of capacitive sensing, and is operable to generate a sensing output, such as an analog signal, in response to touch on or approaching the first substrate 2 by a conductive object, such as a user's finger. In this embodiment, the sensing unit 4 includes first and second electrode layers 41, 42, an insulating layer 43, and a plurality of conducting sections 44.
The first electrode layer 41 is formed on the first surface 21 of the first substrate 2, and is formed with a plurality of first electrode patterns 411 extending in a longitudinal direction (Y), spaced apart from each other in a transverse direction (X) that is transverse to the longitudinal direction (Y), and coupled respectively to the end portions 511 of the first conductive traces 51 of the trace unit 5, as shown in
The insulating layer 43 is formed between the first and second electrode layers 41, 42 for spacing the first electrode layer 41 apart from the second electrode layer 42. In this embodiment, the insulating layer 43 is made from a transparent insulating material, such as transparent plastic, a transparent adhesive or glass.
The conducting sections 44 are disposed between the first and second electrode layers 41, 42. Each conducting section 44 interconnects electrically a corresponding second electrode pattern 421 and the end portion 521 of a corresponding second conductive trace 52 of the trace unit 5, as shown in
The control circuit unit 6 is disposed on the first surface 21 of the first substrate 2, is exposed from the second substrate 3, and is coupled to the first and second conductive traces 51, 52 of the trace unit 5 such that the control circuit unit 6 receives the sensing output generated by the sensing unit 4 through the first and second conductive traces 51, 52 of the trace unit 5. The control circuit unit 6 is operable to generate a control output, such as a digital signal, based on the sensing output received thereby. In this embodiment, the control circuit unit 6 is in the form of a single control chip, and is mounted on the first surface 21 of the first substrate 2 by one of chip-on-glass (COG) process and chip-on-film (COF) process so as to connect electrically the first and second conductive traces 51, 52 of the trace unit 5.
The electrode layer 41′ is formed on the first surface 21 of the first substrate 2, and is formed with a plurality of spaced apart first electrode patterns 411, and a plurality of spaced apart electrode units. The first electrode patterns 411 are identical to those of the first preferred embodiment. The electrode units are arranged in the longitudinal direction (Y). Each electrode unit is spaced apart from the first electrode patterns 411, and includes a plurality of spaced apart second electrode patterns 412 arranged in the transverse direction (X).
The insulating layer 43′ is formed on the electrode layer 41′ for covering entirely the first electrode patterns 411. The insulating layer 43′ is formed with a plurality of through holes 431 corresponding respectively to the second electrode patterns 412 of the electrode units such that said second electrode patterns 412 are exposed from the insulating layer 43′ through the through holes 431. In this embodiment, the insulating layer 43′ is made from a transparent insulating material, such as transparent plastic, a transparent adhesive or glass.
The bridging members 45 are formed between the insulating layer 43′ and the second surface 31 of the second substrate 3, and are coupled respectively to the end portions 521 of the second conductive traces 52 of the trace unit 5. Each bridging member 45 extends in the transverse direction (X) across the first electrode patterns 411, and is spaced apart from the first electrode patterns 411 by the insulating layer 43′. Each bridging member 45 further extends into corresponding through holes 431 in the insulating layer 43′ so as to contact electrically the second electrode patterns 412 of the corresponding one of the electrode units, as shown in
In sum, since the control circuit unit 6 is mounted on the first surface 21 of the first substrate, the control circuit unit 6 is connected electrically to the sensing unit 4, 4′, 4″ through the first and second conductive traces 51, 52 of the trace unit 5 without the ribbon cable 18 of the aforesaid conventional capacitive touch module. Thus, edge buckling encountered in the aforesaid conventional capacitive touch module can be avoided, thereby reducing interference during transmission. As a result, the touch module 100, (100a), (100b), (100c) of the present invention can be easily assembled and can be fabricated with enhanced production yield. On the other hand, the first and second substrates 2, 3 and the control circuit unit 6, 6′ can be configured so that the touch module 100, (100a), (100b), (100c) of the present invention can be applied to various electronic devices with different size specifications with minimized interference.
While the present invention has been described in connection with what are considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
Number | Date | Country | Kind |
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099201763 | Jan 2010 | TW | national |