The entire contents of Taiwan Patent Application No. 097131865, filed on Aug. 21, 2008, from which this application claims priority, are incorporated herein by reference.
1. Field of the Invention
The present invention relates to touch panels, and more particularly to optical touch-control devices combining diode lasers and triangulation methods for detecting touch positions on touch panels.
2. Description of the Related Art
Input modes of conventional touch panels include a resistive mode, a capacitive mode, an optical mode, and others. The resistive mode and the capacitive mode are performed by touching the surface of the touch panel with a finger to effectuate a change of the voltage and current at the touch position of the touch panel thereby enabling detection of the touch position on the touch panel.
However, in a conventional touch panel employing the resistive or capacitive input mode, the touch-control structure consists of a number of thin-film layers, and the transparent capabilities (such as the transparency, the color distortion, the reflective property, the resolution, etc.) of the thin-film layers can affect the visual effect of the touch panel. Such conventional touch panels employing the resistive or capacitive touch-control input modes inevitably reduce rather than enhance the visual effect (e.g., appearance to a user) thereby causing a commensurate reduction in usability. Furthermore, the surface of the touch panel must be touched or even pressed by the finger of a user to ensure a proper input effect. This requirement commonly results in surface scratches and damage, resulting in the transparent capabilities of the touch panel being adversely impacted at the expense of usability of the device.
Conventional touch panels employing the optical input mode use light to detect the touch position on the surface of the touch panel, which is touched by the finger. Accordingly, this will not impact the transparency capabilities of the touch panel and will achieve a better visual effect than touch panels employing resistive or capacitive touch-control input modes. Implementations of the optical input mode include the triangulation method (for example, as disclosed in US Patent Publication No. 2001/0055006A1), the optical distance time difference measuring method (for example, as disclosed in U.S. Pat. No. 5,196,835 and China Patent Publication No. CN1568452A), the on-off directly reading method (for example, as disclosed in U.S. Pat. No. 7,133,031 and China Patent Application No. 200510097130.2), and the image interpretation method (for example, as disclosed in US Patent Publication No. 2005/0275618 and U.S. Pat. No. 7,242,388).
For the above triangulation method, the touch-control technology disclosed in the US Patent Publication No. 2001/0055006A1 mainly employs an actuator (motor and/or oscillator) to continuously rotate or oscillate a polygon mirror for reflecting the focused light emitted from a diode laser, such that several reflective materials about the periphery of the touch panel are scanned, and the light reflected by the reflective materials is indirectly received by a photo-detector, which is integrated with the diode laser in a module, to detect the touch position of the surface of the touch panel. However, a disadvantage of this structure is that electromagnetic waves generated by the motor and oscillator can greatly interfere with the communication quality of electrical products using the touch panel. Furthermore, the bulk and the power consumption of the motor and the oscillator are not small, thus disadvantageously reducing the capability for light-weight and energy-saving designs of the products. In addition, since the diode laser and the photo-detector are integrated in the same module, the photo-detector only can receive the light reflected by the reflective materials at particular angles. Thus, with the amount of received light being insufficient, the signal-to-noise ratio, too, is bad and should be improved.
A need has thus arisen to propose a novel optical diode laser touch-control device for overcoming the disadvantages mentioned above.
To solve the above problems plaguing the prior art, the present invention provides an optical diode laser touch-control device, particularly one that employs continuous interlaced light and ways of directly sensing the interlaced light to perform touch detection and determine touch position using the triangulation method, for facilitating light-weight and energy-saving designs of electrical products.
According to one embodiment, an optical diode laser touch-control device includes a touch panel, at least two light emitters, and a number of receivers. The touch panel has a touch-acting area, and the two light emitters are disposed on two adjacent corners of the touch panel respectively. Each light emitter includes a diode laser and a lens. The diode laser is integrated in the corresponding light emitter by a semiconductor packaging technology, and the lens is integrated in the corresponding light emitter by the semiconductor packaging technology and arranged between the diode laser and the touch-acting area. The light is emitted continuously from the diode laser and is refracted by the lens to continuously emit a diffused light to cover the touch-acting area for forming an interlaced touch screen. The receivers, which are capable of receiving the diffused light, are disposed on the touch panel around the touch-acting area to receive the diffused light.
Many aspects of the embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosures. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Reference will now be made to the drawings to describe exemplary embodiments of the present optical diode laser touch-control device, in detail. The following description is given by way of example, and not limitation.
In the embodiment, angles between the projection directions of the light emitted from the first light emitter 21 and the boundary of the touch-acting area 10 is about 10-80 degrees as shown in
The cross sections of the lenses 212, 222 of the first and second light emitters 21, 22 represent a cambered profile (as shown in
The diffused light 31, 32 may be invisible light, such as one or more of infrared light and ultraviolet light, etc. Furthermore, the receivers 4 are arranged around the touch-acting area 10 in a U shape (as shown in
The present embodiment may be performed by a combination of the above elements. Specifically, when the finger 5 of the user touches the touch-acting area 10 of the touch panel 1 (as shown in
According to the embodiment discussed above, the diode lasers 211, 221 and the lenses 212, 222 are packaged or integrated into the respective light emitters 21, 22, which are then used as the light sources for directly emitting the diffused light 31, 32 to cover the touch-acting area 10. Thus the present embodiment can omit the motor and the oscillator of the prior art to ensure or enhance communication quality of the products, and can reduce the volume of the diode lasers 211, 221 and the lenses 212, 222 to facilitate light-weight and energy-saving designs of the electrical products. Simultaneously, the present embodiment employs the receivers 4 to directly sense the change of the light 31, 32 to replace the reflective materials of the prior art, such that the input sense resolution of the touch panel may be improved.
Given the above disclosure, one skilled in the art could devise variations that are within the scope and spirit of the invention disclosed and referenced herein, including modifications to configurations, ways, materials, and/or designs. Further, the various features of the embodiments disclosed and referenced herein can be used alone, or in varying combinations and permutations with each other, to the extent not mutually exclusive, and are not intended to be limited to the specific combinations described herein. Thus, the scope of the claims is not to be limited by the illustrated embodiments.
| Number | Date | Country | Kind |
|---|---|---|---|
| 097131865 | Aug 2008 | TW | national |