This application claims the priority benefit of Taiwan application serial no. 104122093, filed on Jul. 8, 2015. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
Field of the Invention
The invention is directed to a detecting method and an apparatus related thereto and more particularly, to a method of detecting a touch position and a touch apparatus thereof.
Description of Related Art
Electronic devices or display screens having a touch function have gradually become a development trend of today's technology, and by means of the touch function, users can control the electronic apparatuses and the display screens or perform an input operation on the electronic apparatuses and the display screens. Based on the different design principles, the touch function is implemented by means of an optical touch module, a capacitive type touch module or a resistive type touch module.
Generally, a typical optical touch module is composed of two lenses. The lenses observe a touch object from different positions and then, calculate touched points based on obtained touch information, and thereby, a touch position of the touch object is obtained. In a case where a single touch object is detected, the two lenses of the optical touch module respectively outputs the obtained touch information, and touched points may be correctly obtained through cross-comparing the touch information. However, in a case where a plurality of touch objects is detected, substantially inexistent touched points (i.e., so-called ghost points) may be generated during the cross-comparing process merely according to the touch information obtained by the two lenses of the single optical touch module.
In order to prevent the ghost points from affecting the operation of the touch function, a solution is to detect the touch positions of the touch objects by using a plurality of optical touch modules, such that the optical touch modules in different directions may be capable of detecting the matched touched points for the touch positions where the touch objects are located. In other words, actually existent touched points and the ghost points can be distinguished by comparing the touched points obtained by different optical touch modules. However, in actual operation, due to difference in resolutions and disposition positions of the lenses, positional deviations may occur in the touched points, even though corresponding to the touch positions of the touch objects, obtained by the optical touch module in different directions. In this case, the touch positions of the touch objects cannot correctly determined by means of comparing.
The invention provides a method of detecting a touch position and a touch apparatus thereof capable of effectively determining substantially existent touched points and filtering out ghost points, so as to correctly detect a touch position where a touch object is located.
According to an embodiment of the invention, a method of detecting a touch position applicable to a touch apparatus having a touch surface and configured to detect a touch position of a touch object on the touch surface is provided. The method includes the following steps. At least three intervally distributed light sensing devices are provided to obtain a plurality of touch information. Each of the touch information comprises at least one peak value corresponding to each touch object. Based on the peak values of the touch information, a total number of the touched points on the touch surface is determined. If the total number of the touched points is determined as being greater than 1, the plurality of touched points on the touch surface is calculated based on the peak values of the touch information. A plurality of to-be-examined touched points corresponding to one of the peak values of first touch information is obtained from the touched points. The first touch information has the greatest number of peak values among the plurality of touch info nation. According to a plurality of distance values among the to-be-examined touched points, a first to-be-examined touched point and a second to-be-examined touched point are selected. Whether the first to-be-examined touched point and the second to-be-examined touched point are simultaneously corresponding to any one of the peak values of all the touch information is examined. If the first to-be-examined touched point and the second to-be-examined touched point are respectively and simultaneously corresponding to any one of the peak values of all the touch information, the touch position is determined according to the first to-be-examined touched point and the second to-be-examined touched point.
According to another embodiment of the invention, a touch apparatus including at least three light sensing devices, a capture module, a determination module, a calculation module, a selection module, an examine module and an output module is provided. The light sensing devices are intervally distributed around a touch surface of the touch apparatus, and configured to respectively detect a touch object on the touch surface to generate a plurality of touch information to determine a touch position of the touch object. The capture module is coupled to the light sensing devices, and controls the light sensing devices to obtain the touch information. Each of the touch information includes at least one peak value corresponding to each touch object. The determination module is coupled to the capture module, and determines a total number of the touched points on the touch surface according to the peak values of the plurality of touch information. The calculation module is coupled to the determination module, and if the total number of the touched points is determined as being greater than 1, the calculation module calculates the plurality of touched points on the touch surface based on the peak values of the touch information. The selection module is coupled to the calculation module and obtains a plurality of to-be-examined touched points corresponding to one of the peak values of first touch information from the touched points. The selection module selects a first to-be-examined touched point and a second to-be-examined touched point according to a plurality of distance values among the to-be-examined touched points. The first touch information has the greatest number of peak values among the plurality of touch information. The examine module is coupled to the selection module, and examines whether the first to-be-examined touched point and the second to-be-examined touched point are simultaneously corresponding to any one of the peak values of all the touch information. The output module is coupled to the examine module, and if the first to-be-examined touched point and the second to-be-examined touched point are respectively and simultaneously corresponding to any one of the peak values of all the touch information, the output module determines the touch position according to the first to-be-examined touched point and the second to-be-examined touched point.
To sum up, in the touch position detecting method and the touch apparatus thereof provided by the embodiments of the invention, a plurality of touch information is obtained by the at least three light sensing devices, and the total number of the touched points on the touch surface can be deduced. When the total number of the touched points is greater than 1, the touch information having the greatest number of peak values is selected from the touch information to serve as the first touch information, and the touch position corresponding to a single peak value is analyzed. To be more detailed, in the method of detecting the touch position, the first to-be-examined touched point and the second to-be-examined touched point having the greatest possibility of being the actual touched points are selected from the to-be-examined touched points corresponding to the single peak value of the first touch information and being examined. Once the first to-be-examined touched point and the second to-be-examined touched point pass the examination, a more accurate touch position can be calculated according to the first to-be-examined touched point and the second to-be-examined touched point. For all the peak values of the first touch information, the steps of the touch position detecting method can be further performed one by one to obtain the touch position corresponding to all the peak values. Thereby, actual touched points can be obtained, and the ghost points can be correctly filtered by the method of detecting the touch position and the touch apparatus thereof.
In order to make the aforementioned and other features and advantages of the invention more comprehensible, several embodiments accompanied with figures are described in detail below.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
In an optical touch apparatus, ghost points have to be filtered out if touch positions of a plurality of touch objects are desired to be deduced and obtained. Specially, the ghost points are generated usually due to operations of the optical touch apparatus.
Nevertheless, referring to
Ghost points would cause malfunction in touch operations, and thus, it is important to filter out the ghost points. A common method is to detect the touched points by using multiple optical touch modules for filtering out the ghost points. Referring to
However, in actual use, the arrangement of the lenses may be affected by resolution and assembly offsets, such that the touched points measured by different optical touch modules would essentially lead to deviations. Referring to
The touch apparatus 100 includes a plurality of light sensing devices. In the present embodiment, four light sensing devices Ca, Cb, Cc and Cd are, for example, optical lenses including photosensitive elements, such as charge coupled devices (CCD) or other complementary metal oxide semiconductors (CMOS). Referring to
To be specific, the touch information generally include brightness information detected by the light sensing devices Ca, Cb, Cc and Cd within detection ranges thereof, and a detection range of each of light sensing devices Ca, Cb, Cc and Cd may be, for example, an angle range of 0 degrees. Taking the embodiment illustrated in
The touch apparatus 100 further includes a capture module 130, a determination module 140, a calculation module 150, a selection module 160, an examine module 170 and an output module 180 which are configured to receive the touch information captured by the light sensing devices Ca, Cb, Cc and Cd and perform relative procedures to obtain a touch position of the touch object Ob. In the present embodiment, the capture module 130, the determination module 140, the calculation module 150, the selection module 160, the examine module 170 and the output module 180 are, for example, a plurality of software procedures performed by a processing unit 120. The processing unit 120 may be, for example, a programmable microprocessor, a digital signal processor (DSP), a programmable controller, application specific integrated circuits (ASIC), a programmable logic device (PLD) or the like. However, in other embodiments, the capture module 130, the determination module 140, the calculation module 150, the selection module 160, the examine module 170 and the output module 180 may also be implemented by a plurality of circuits.
Then, in step S320, the determination module 140 determines total a number of the touched points on the touch surface 110 based on a plurality of peak values of the touch information. To be detailed, the determination module 140 performs cross-comparing based on a total number of the peak values of each touch information, so as to calculate the total number of the touched points on the touch surface 110. If the determination module 140 determines that the total number of the touched point on the touch surface 110 is equal to 1, as illustrated in
In contrast, if the determination module 140 determines that the total number of the touched points is more than 1, as illustrated in
Referring to
After the first touch information is selected, the selection module 160 further selects a plurality of to-be-examined touched points ca-1, ca-2, cb-1, cd-1 and cd-2 corresponding to one of the peak values of the first touch information from the touched points. As illustrated in
Generally, the touched points corresponding to the same touch object, but obtained by combinations of different light sensing devices may have deviations among one another, but will not be different too far. Therefore, in the touch position detecting method of the present embodiment, when the first to-be-examined touched point and the second to-be-examined touched point are selected, two of the to-be-examined touched points having the smallest distance from each other are selected as the first to-be-examined touched point and the second to-be-examined touched point, but the invention is not limited thereto, and the first to-be-examined touched point and the second to-be-examined touched point may also be selected from the plurality of to-be-examined touched points according to other standards. Then, referring to
That is to say, to each of the touch information, it is determined that whether any one of the peak values is corresponding to the first to-be-examined touched point, and whether any one of the peak values is corresponding to the second to-be-examined touched point. In other words, taking
Afterwards, in step S362, whether the first to-be-examined touched point is also simultaneously located in a peak value range of any one of the peak values of other touch information that does not belong to the first portion of the touch information is examined. Referring to
Being similar to steps S361 and S362, in step S363, a second portion of the touch information for obtaining the second to-be-examined touched point is determined. In the present embodiment, the second to-be-examined touched point cd-1 is an intersection point of the solid line Cc1 and the solid line Cd1. In other words, the second to-be-examined touched point cd-1 is obtained through cross-comparing the peak values of the touch information of the light sensing device Cc and the peak values of the touch information of the light sensing device Cd. Thus, the second portion of the touch information includes the touch information of the light sensing devices Cc and Cd. Afterwards, in step S364, whether the second to-be-examined touched point is located in the peak value range of any one of the peak values of other touch information that does not belong to the second portion of the touch information is also examined. Namely, as for the preceding embodiment, whether the second to-be-examined touched point cd-1 is also located in ranges of the peak values of the touch information of the light sensing devices Ca and Cb is also examined. According to the embodiment illustrated in
In step S365, if the first to-be-examined touched point is simultaneously located in the peak value range of any one of the peak values of other touch information that does not belong to the first portion of the touch information, and the second to-be-examined touched point is simultaneously located in the peak value range of any one of the peak values of other touch information that does not belong to the second portion of the touch information, it is determined that the first to-be-examined touched point and the second to-be-examined touched point are simultaneously corresponding to any one of the peak values of all the touch information. With reference to the embodiment illustrated in
Referring to
Referring to
In the embodiments above, after determining a touch position corresponding to a peak value (e.g., the solid line Cc1) of the first touch information (e.g., the touch information of the light sensing device Cc), the touch apparatus 100 further determines a touch position corresponding to another peak value of the first touch information. In this case, as for the touch position detecting method illustrated in
To summarize, in the touch position detecting method and the touch apparatus thereof provided by the embodiments of the invention, a plurality of touch information is obtained by the at least three light sensing devices, and the total number of the touched points and all possible touched points on the touch surface can be deduced. Then, for each touch object, the most possible multiple touched points are correspondingly selected and examined for mathematical calculation to recognize the touch positions of the touch objects. Accordingly, the touch position detecting method and the touch apparatus thereof can filter out the ghost points on the touch surface and accurately determine the touch positions of the touch objects, so as to achieve better touch detection.
Although the invention has been described with reference to the above embodiments, it will be apparent to one of the ordinary skill in the art that modifications to the described embodiment may be made without departing from the spirit of the invention. Accordingly, the scope of the invention will be defined by the attached claims not by the above detailed descriptions.
Number | Date | Country | Kind |
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104122093 | Jul 2015 | TW | national |