Patent Publication Number: US-2016239144-A1

Title: Touchscreen device and its touch trajectory sensing method

Description:
This application claims the priority benefit of Taiwan patent application number 104105595, filed on Feb. 17, 2015. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to touch control technology and more particularly, to a touchscreen device and its touch trajectory sensing method, wherein when multiple objects are moved into contact with the touch sensing panel of the touchscreen device and stayed at the respective touch points or moved, the touch trajectory sensing method determines the moving trajectory of each object on the touch sensing panel of the touchscreen device and the trajectory sensing area around each touch point according to the movement speed of the respective touch point, preventing from making a wrong moving trajectory determination and eliminating the touch sensing panel from performing an unexpected touch control operation. 
     2. Description of the Related Art 
     In order to mate with human intuition, touchscreen device has been widely used in a variety of modern electronic devices, allowing the user to operate the electronic device by touching the touch sensing panel of the touchscreen device of the electronic device using one finger or a conductive stylus. 
       FIGS. 13-15  illustrate different application examples of a touch trajectory sensing method according to the prior art. As illustrated, when an object (such as finger or conductive stylus) is moved on a touch sensing panel of a touchscreen device to create a moving trajectory K 1 , a control unit of the touchscreen device acquires a first touch point M 11  from the touch sensing panel, and then defines a first trajectory sensing area A 11  around the first touch point M 11 . When a next sensing time is up, the control unit detects a second touch point M 12  in the first trajectory sensing area A 11  within the touch sensing panel, and then defines a second trajectory sensing area A 12  around the second touch point M 12  for determining a moving trajectory from the second touch point M 12  to the third touch point M 13  using the second trajectory sensing area A 12 . 
     When two objects are moved on the touch sensing panel to create two moving trajectories K 1 ,K 2 , the control unit sequentially detects first touch points M 11 ,M 21 , second touch points M 12 ,M 22  and third touch points M 13 ,M 23 . However, when these two objects are moved from the respective second touch points M 12 ,M 22  to the respective third touch point M 13 ,M 23 , the third touch point M 23  is disposed near the second touch point M 12  and falls within the second trajectory sensing area A 12  of the second touch point M 12 , and the control unit can erroneously determine the second touch point M 12  and the third touch points M 13 ,M 23  to be of one same moving trajectory, causing the touch sensing panel to perform an unexpected touch control operation. 
     Therefore, how to prevent a control unit of a touchscreen device from making a wrong moving trajectory determination when multiple objects are forced into contact with a touch sensing panel of the touchscreen device and moved on the touch sensing panel to perform a special sliding action such as change of direction is the goal manufacturers engaged in this industry are anxious to achieve. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide a touchscreen device and its touch trajectory sensing method, which defines a second trajectory sensing area using the movement speed of the touch point, preventing from making a wrong moving trajectory determination and eliminating the touch sensing panel from performing an unexpected touch control operation. 
     When multiple objects are moved into contact with the touch sensing panel of the touchscreen device and stayed at the respective touch points or moved, the touch trajectory sensing method determines the moving trajectory of each object on the touch sensing panel of the touchscreen device and the trajectory sensing area around each touch point according to the movement speed of the respective touch point, where the trajectory sensing area exhibits a positive correlation with the movement speed. Thus, when multiple objects are simultaneously moved into contact with the touch sensing panel and then stayed at the respective touch points, or steered on the touch sensing panel, each touch point has a relatively smaller trajectory sensing area at the turning point or retarded point on the touch sensing panel, preventing adjacent touch points at different moving trajectories from falling to the respective opponent second trajectory sensing areas to further eliminate the control unit from making a wrong moving trajectory determination on the adjacent touch points, and thus, the invention can provide the user with excellent touch operation experience. 
     Other advantages and features of the present invention will be fully understood by reference to the following specification in conjunction with the accompanying drawings, in which like reference signs denote like components of structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic circuit diagram of a touchscreen device in accordance with the present invention. 
         FIG. 2  is an operation flow chart of a touch trajectory sensing method in accordance with the present invention. 
         FIG. 3  is a schematic drawing illustrating two fingers touched the touch sensing panel of the touchscreen device in accordance with the present invention. 
         FIG. 4  is a schematic drawing illustrating a first application example of the touch trajectory sensing method in accordance with the present invention (I). 
         FIG. 5  is a schematic drawing illustrating a first application example of the touch trajectory sensing method in accordance with the present invention (II). 
         FIG. 6  is a schematic drawing illustrating a first application example of the touch trajectory sensing method in accordance with the present invention (III). 
         FIG. 7  is a schematic drawing illustrating a second application example of the touch trajectory sensing method in accordance with the present invention (I). 
         FIG. 8  is a schematic drawing illustrating a second application example of the touch trajectory sensing method in accordance with the present invention (II). 
         FIG. 9  is a schematic drawing illustrating a second application example of the touch trajectory sensing method in accordance with the present invention (III). 
         FIG. 10  is a schematic drawing illustrating a third application example of the touch trajectory sensing method in accordance with the present invention (I). 
         FIG. 11  is a schematic drawing illustrating a third application example of the touch trajectory sensing method in accordance with the present invention (II). 
         FIG. 12  is a schematic drawing illustrating a third application example of the touch trajectory sensing method in accordance with the present invention (III). 
         FIG. 13  is a schematic drawing illustrating an application example of a touch trajectory sensing method according to the prior art (I). 
         FIG. 14  is a schematic drawing illustrating an application example of a touch trajectory sensing method according to the prior art (II). 
         FIG. 15  is a schematic drawing illustrating an application example of a touch trajectory sensing method according to the prior art (III). 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , a touchscreen device  1  in accordance with the present invention is shown. As illustrated, the touchscreen device  1  comprises a touch sensing panel  11  and a control unit  12 . The touch sensing panel  11  comprises a plurality of driving lines  111  transversely arranged in parallel and electrically coupled to the control unit  12 , a plurality of sensing lines  112  longitudinally arranged in parallel and electrically coupled to the control unit  12  and respectively intersected with the driving lines  111  to form a Cartesian coordinate system, and a sensing point  113  located at each intersection between each driving line  111  and each sensing line  112  corresponding to one respective coordinate in the Cartesian coordinate system. 
     In this embodiment, the driving lines  111  and the sensing lines  112  are intersected to form a Cartesian coordinate system. However, this example is not a limitation. In actual application of the touch trajectory sensing method, the driving lines  111  can be arranged in the touch sensing panel  11  in a radial manner to extend from the center of the touch sensing panel  11  radially toward the border edge thereof, and the sensing lines  112  can be concentrically arranged in the touch sensing panel  11  and intersected with the radially extending driving line  111  to form a polar coordinate system so that a sensing point  13  is formed at each intersection between each driving line  111  and each sensing line  112  corresponding to one respective coordinate in the polar coordinate system. 
     Referring to  FIG. 2 , the implementation of the touch trajectory sensing method in the touchscreen device comprises the steps of: 
     ( 300 ) Control unit  12  acquires a first touch point M 11  from one sensing point  113  of the touch sensing panel  11 . 
     ( 301 ) Control unit  12  defines a first trajectory sensing area A 11  around the first touch point M 11 . 
     ( 302 ) Control unit  12  acquires a second touch point M 12  from a sensing point  113  of the touch sensing panel  11 . 
     ( 303 ) Control unit  12  determines whether the second touch point M 12  is within the first trajectory sensing area A 11  or not, and then proceeds to step ( 304 ) if negative, or step ( 305 ) if positive. 
     ( 304 ) Control unit  12  determines the first touch point M 11  and the second touch point M 12  are not the same moving trajectory. 
     ( 305 ) Control unit  12  determines the movement from the first touch point M 11  to the second touch point M 12  is in the same moving trajectory K 1 . 
     ( 306 ) Control unit  12  computes the movement speed V 12  of the second touch point M 12 . 
     ( 307 ) Control unit  12  defines a second trajectory sensing area A 12  around the second touch point M 12  according to the movement speed V 12 . 
     Referring to  FIGS. 3-6 , when two parallel objects (such as two fingers) simultaneously touch the touch sensing panel  11  and move on the touch sensing panel  11  in one same direction to create respective moving trajectories K 1 ,K 2 , the control unit  12  will be able to detect the location information of two first touch points M 11 ,M 21  from two sensing points  113  at the touch sensing panel  11 . After detection of the location information, the control unit  12  will draw a respective perfect circle with the center at each first touch point M 11 ,M 21  using a first sensing radius R 11 ,R 21 , and then define a respective first trajectory sensing area A 11 ,A 21  around the respective first touch point M 11 ,M 21 . 
     If the first touch points M 11 ,M 21  are the respective initial touch points of the respective moving trajectories K 1 ,K 2 , the control unit  12  defines the first sensing radius R 11 ,R 21  of the respective first trajectory sensing area A 11 ,A 21  according to a predetermined initial value; if the first touch points M 11 ,M 21  are not the respective initial touch points of the respective moving trajectories K 1 ,K 2 , it means that each first touch point M 11 ,M 21  has a respective movement speed V 11 ,V 21 , and thus, the control unit  12  defines the first sensing radius R 11 ,R 21  of the respective first trajectory sensing area A 11 ,A 21  according to the movement speed V 11 ,V 21 , where the first sensing radius R 11 ,R 21  exhibits a positive correlation with the movement speed V 11 ,V 21  of the respective first touch point M 11 ,M 21 . 
     Thereafter, the control unit  12  detects the location information of two second touch points M 12 ,M 22  from respective two sensing points  113  at the touch sensing panel  11 , where these two second touch points M 12 ,M 22  are respectively located within the respective first trajectory sensing areas A 11 ,A 21 , and therefore, the control unit  12  determines the first touch point M 11  and the second touch point M 12  are of one same moving trajectory K 1 , the first touch point M 21  and the second touch point M 22  are of another same moving trajectory K 2 . 
     Because the second touch point M 12  is not within the respective first trajectory sensing area A 21  and the second touch point M 22  is not within the respective first trajectory sensing area A 11 , the control unit  12  determines that the first touch point M 11  and the second touch point M 22  are not in one same moving trajectory; the first touch point M 21  and the second touch point M 12  are not in one same moving trajectory. 
     After the control unit  12  determined that the first touch points M 11 ,M 21  and the second touch points M 12 ,M 22  are respectively located within the respective moving trajectories K 1 ,K 2 , the control unit  12  immediately computes the movement speed V 12 ,V 12  of each second touch point M 12 ,M 22 , and then defines a second sensing radius R 12 ,R 22  for each second touch point M 12 ,M 22  according to the respective movement speed V 12 ,V 12 , and then draws a respective perfect circle with the center at each second touch point M 12 ,M 22  using the second sensing radius R 12 ,R 22  and then defines a respective second trajectory sensing area A 12 ,A 22  around the respective second touch point M 12 ,M 22  using the respective perfect circle thus obtained. 
     The length of each second sensing radius R 12 ,R 22  exhibits a positive correlation with the movement speed V 12 ,V 22 , and therefore, the second trajectory sensing area A 12 ,A 22  around the respective second touch point M 12 ,M 22  exhibits a positive correlation with the movement speed V 12 ,V 22 .When the moving direction of an object is changed, its movement speed is lowered, and therefore the second trajectory sensing area A 12 ,A 22  around the respective second touch point M 12 ,M 22  will be relatively reduced subject to reduction of the movement speed V 12 ,V 22 , shortening the second sensing radius R 12 ,R 22 . 
     Thereafter, the control unit  12  will detect the location information of third touch points M 13 ,M 23  adjacent to the respective second touch points M 12 ,M 22 . Because these third touch points M 13 ,M 23  are respectively located within the respective second trajectory sensing areas A 12 ,A 22 , the control unit  12  determines that the second touch point M 12  and the third touch point M 13  are in one same moving trajectory K 1 ; the second touch point M 22  and the third touch point M 23  are in another same moving trajectory K 2 . 
     Because the second sensing radius R 12  of the second trajectory sensing area A 12  exhibits a positive correlation with the movement speed V 12 , is relatively reduced second trajectory sensing area A 12  around the second touch point M 12  to provide a reduced second sensing radius R 12  subject to reduction of the movement speed V 12  at the turning point, and thus, the third touch point M 23  near the second touch point M 12  is not located within the second trajectory sensing area A 12 , preventing the control unit  12  from determining the second touch point M 12  and the third touch point M 23  to be within one same moving trajectory to further cause the touch sensing panel  11  to perform an unexpected touch control operation, and thus, the invention can provide the user with excellent touch operation experience. 
     The second sensing radiuses R 12 ,R 22  of the aforesaid second trajectory sensing areas A 12 ,A 22  are smaller than a predetermined upper limit value, preventing certain touch points near the second touch points M 12 ,M 22  from falling to the respective opponent second trajectory sensing areas A 12 ,A 22  due to an excessive high movement speed V 12 ,V 22  of the two objects so as to further eliminate the control unit  12  from making a wrong moving trajectory determination on the second touch points M 12 ,M 22  and the follow-up third touch points M 13 ,M 23 . 
     Referring to  FIGS. 7-9  and  FIG. 3  again, when two parallel objects simultaneously touch the touch sensing panel  11  and move on the touch sensing panel  11  inwardly in direction toward each other to create respective moving trajectories K 1 ,K 2 , because the second sensing radiuses R 12 ,R 22  of the second trajectory sensing areas A 12 ,A 22  respectively exhibit positive correlation with the respective movement speeds V 12 ,V 22 , the second trajectory sensing areas A 12 ,A 22  around the respective second touch points M 2 ,M 22  are relatively reduced subject reduction of the respective movement speeds V 12 ,V 22  at the respective turning points, thereby shortening the respective second sensing radiuses R 12 ,R 22 , and therefore, the two adjacent second touch points M 12 ,M 22  fall into the respective second trajectory sensing areas A 12 ,A 22 , preventing the control unit  12  from determining the second touch points M 12 ,M 22  to be within one same moving trajectory. 
     Referring to  FIGS. 10-12  and  FIG. 3  again, when an object simultaneously touches the touch sensing panel  11  and is then stayed at the touch point to create a moving trajectory K 1 , because the second sensing radius R 12  of the second trajectory sensing area A 12  exhibits a positive correlation with the movement speed V 12 , the movement speed V 12  of the second touch point M 12  is zero. At this time, the second trajectory sensing area A 12  around the second touch point M 12  is reduced subject to the zeroed movement speed V 12 , and thus, the follow-up touched first touch point M 21  near the second touch point M 12  will not fall within the second trajectory sensing area A 12 , preventing the control unit  12  from determining the second touch point M 12  and the first touch point M 21  to be within one same moving trajectory. 
     In the above-described first, second and third application examples, two objects are moved into contact with two adjacent locations at the touch sensing panel  11 , and then stayed immovable or simultaneously moved along the surface of the touch sensing panel  11 . However, these application examples are not intended to limit the scope of the present invention. In actual application of the touch trajectory sensing method, the method can determine the moving trajectory of one, two, three, four or even five objects at the touch sensing panel  11 , where the movement speed of the touch point of each object exhibits a positive correlation with the respective trajectory sensing area. 
     It is to be noted that the implementation that the touch trajectory sensing method determines the second trajectory sensing area A 12  of the second touch point M 12  according to the movement speed V 12  of the second touch point M 12  is simply an example but not intended for use to limit the scope of the present invention. When multiple objects are moved on the touch sensing panel  11  to generate multiple moving trajectories (such as moving trajectories K 1 ,K 2 ), the control unit  12  will acquire multiple touch points (such as first touch points M 11 ,M 21 , second touch points M 12 ,M 22 , third touch points M 13 ,M 23 , etc.) from the respective moving trajectories in a proper order, and then define the respective trajectory sensing areas (such as second trajectory sensing areas A 12 ,A 22 ) around the acquired touch points according to the respective movement speeds (such as movement speeds V 12 ,V 22 , etc.). Because the respective sensing radius (such as second sensing radius R 12 ,R 22 , etc.) of the respective trajectory sensing areas exhibit a positive correlation with the movement speeds of the respective touch points, when multiple objects, when multiple objects are operated to perform special sliding operations such as stayed at respective touch points on the touch sensing panel  11  or change of direction, each touch point has a relatively smaller trajectory sensing area at the turning point or retarded point on the touch sensing panel  11 , preventing adjacent touch points at different moving trajectories from falling to the respective opponent second trajectory sensing areas to further eliminate the control unit  12  from making a wrong moving trajectory determination on the adjacent touch points and causing the touch sensing panel  11  to perform an unexpected touch control operation, and thus, the invention can provide the user with excellent touch operation experience. 
     In conclusion, the invention provides a touchscreen device and a touch trajectory sensing method used in the touchscreen device and adapted for determining the moving trajectory of each object being moved into contact with the touch sensing panel  11  of the touchscreen device  1  and the trajectory sensing area around each touch point according to the movement speed of the respective touch point, where the trajectory sensing area exhibits a positive correlation with the movement speed so that when multiple objects are simultaneously moved into contact with the touch sensing panel  11  and then stayed at the respective touch points, or steered on the touch sensing panel  11 , each touch point has a relatively smaller trajectory sensing area at the turning point or retarded point on the touch sensing panel  11 , preventing adjacent touch points at different moving trajectories from falling to the respective opponent second trajectory sensing areas to further eliminate the control unit  12  from making a wrong moving trajectory determination on the adjacent touch points. 
     Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.