Abstract:
A touch input control method comprising steps is provided: displaying an interface comprising at least one object; gathering signals as to actual touches for calibration purposes. In use, calculating coordinates of the touch; determining whether the coordinates of the actual touch match the predetermined touch coordinates of the object; creating an adjustment signal if the coordinates of the touch is not the same as the predetermined touch coordinates of any object; determining which finger used for touch input, and retrieving a touch offset direction and a touch offset distance of the determined finger of the user from a calibration database; and applying compensation to the coordinates of the touch, so as to determine the touched object. An electronic device using the touch input control method is also provided.

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to an electronic device and a touch input control method thereof. 
     2. Description of Related Art 
     Electronic devices with touch screens, mobile phones, digital photo frames, electronic readers (e-reader), for example, are popular. The user inputs information by touching objects such as icons and virtual keyboard displayed on the touch screen. Usually, each of the objects displayed on the touch screen associates with a predefined touch coordinates. When the user touches the touch screen, the electronic device detects the coordinates of the touched portion, compares and analyzes the coordinates touched with the predefined coordinates of the object, so determining the object that the user has touched. However, due to the different touch habits, such as individual parallax, different fingers used for touching, different manners and different orientations for gripping the devices, when the user touches an object displayed on the touch screen, more or less deviation occurs between the coordinates touched and the predetermined coordinates of the object, which results in wrong determinations and input errors. 
     Therefore, what is needed is an electronic device and a touch input control method thereof to alleviate the limitations described above. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding sections throughout the several views. 
         FIG. 1  is a block diagram of an electronic device in accordance with an exemplary embodiment. 
         FIG. 2  is a schematic diagram showing the portions touched by a user, displayed on the electronic device of  FIG. 1 . 
         FIGS. 3(   a ) and  3 ( b ) are schematic diagrams showing the portions touched by a user, displayed on the electronic device of  FIG. 1 . 
         FIG. 4  is a flowchart of a touch input control method for electronic devices, such as the one of  FIG. 1 , in accordance with the exemplary embodiments. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is an exemplary embodiment of a block diagram of an electronic device  100 . The electronic device  100  can calibrate the touch position for the user, for the user to be deemed to have accurately touched the objects displayed on the touch screen. The electronic device  100  is a mobile terminal with a touch screen, such as a mobile phone. In alternative embodiments, the electronic device  100  can be other electronic devices with touch screens, such as an electronic reader, a tablet, or a digital phone frame, for example. 
     The electronic device  100  includes a storage unit  10 , a touch screen  20 , and a processor  30 . The touch screen  20  generates signals in response to user touches. The user can activate the touch calibration function, do a touch calibration test, and touch the objects displayed on the touch screen  20 . 
     The storage unit  10  stores a calibration database  12  recording touch calibration data for the fingers of a number of users. The touch calibration data of each finger includes the size of the touched area, shape of the touched area, the touch offset direction, and the touch offset distance, when a finger is attempting to touch a single object. The touch offset direction is the offset direction of the touched point relative to the point having the predefined coordinates of the object which the user intends to touch. The touch offset distance is the offset distance between the touched point and the point having the predefined coordinates of the object which the user intends to touch. 
     When the user activates the touch calibration function of the electronic device  100 , a navigation interface is displayed on the touch screen  20  for prompting the user to do a touch calibration test for the finger or fingers of that user. The electronic device  100  also stores the touch calibration data of the user generated during the touch calibration process, in the calibration database  12 . A user may be in the habit of using a particular finger or several particular fingers for inputting information via the touch screen  20 . And, moreover, when a particular user using a same finger touches each object displayed on the touch screen  20 , the size of the touched area, shape of the touched area, the touch offset direction, and the touch offset distance are expected to be substantially the same. Thus, before the touch calibration test, the electronic device  100  prompts the user to do the test using his/her commonly used finger(s) for touch input. If deviation exists when the user using a same finger touches different objects during the test, the electronic device  100  calculates the average value of each type of the calibration data respectively, and stores the calculated value of each type of the calibration data in the calibration database  12 . 
     The processor  30  includes a figure identification module  31 , a calculation module  32 , a determination module  33 , a touch control module  34 , and a display control module  35 . 
     The display control module  35  controls the touch screen  20  to display an interface including a number of objects. Each object is associated with predetermined touch coordinates. If the coordinates actually touched are the same as the predetermined coordinates associated with an object, then the function or process corresponding to the object is activated. In the embodiment, the object can be a virtual key, or a touch icon or the like. 
     The calculation module  32  calculates the coordinates of the actual touch according to the signals transmitted from the touch screen  20 . 
     The determination module  33  determines whether the coordinates of the actual touch is the same as the predetermined touch coordinates of one of the objects displayed on the touch screen  20 . If the coordinates of the actual touch is the same as the predetermined touch coordinates of one of the objects, the determination module  33  allows a normal signal. If the coordinates of the actual touch does not match any of the predetermined touch coordinates of the objects, the determination module  33  creates an adjustment signal and transmits the adjustment signal to the touch control module  34 , the figure identification module  31 , and to the calculation module  32 . 
     When the adjustment signal transmitted from the determination module  33  is received, the figure identification module  31  identifies the shape of the portion of the finger which actually makes contact with the touch screen  20  (shape of the touched area) according to the signals transmitted from the touch screen  20 , and the calculation module  32  further calculates the size of the touched area. In the embodiment, the calculation module  32  calculates the size of the touched area according to the resolution of the touch screen  20 , and the size of the touch screen  20 . The size of the touch screen  20  is pre-stored in the storage unit  10 . The determination module  33  further determines which finger is used by the user in touching the touch screen  20  according to the size of the touched area, shape of the touched area, and the touch calibration data of the user&#39;s commonly used finger, as recorded in the calibration database  12 . The determination module  33  also retrieves the touch offset direction and the touch offset distance of the finger of the user so determined from the calibration database  12 , and transmits the retrieved data to the touch control module  34 . 
     The touch control module  34  processes the coordinates of the touch of the user according to the normal touch signal and the adjustment signal transmitted from the determination module  33 , so as to determine the object which the user intended to touch. In this embodiment, if a normal signal is received, the touch control module  34  determines that the object associated with the coordinates of the touch is the touched object. If the adjustment signal is received, the touch control module  34  executes the touch coordinates compensation (as hereinafter explained) for the actual touch, and determines the touched object accordingly. 
     In this embodiment, the touch control module  34  executes the touch coordinates compensation for the touch according to the touch offset direction and the touch offset distance of the determined finger, retrieved by the determination module  33 . For example, assuming the coordinates of the touch is (x0, y0), and the touch offset direction retrieved by the determination module  33  is precisely southwest of the predetermined touch coordinates (where the touch screen is upright and due north is vertically upwards) and the touch offset distance retrieved by the determination module  33  is one unit length leftward in the horizontal direction and one unit length downward in the vertical direction relative to the predetermined touch coordinates, the touch control module  34  applies compensation equal to the total displacement, that is, the touch coordinates compensation is (x0−1, y0−1). For another example, assuming the coordinates of the actual touch are (x+1, y+1), the touch offset direction retrieved by the determination module  33  is precisely northeast relative to the predetermined touch coordinates, and the touch offset distance retrieved by the determination module  33  is one unit length rightward in the horizontal direction and one unit length upward in the vertical direction relative to the predetermined touch coordinates, the touch control module  34  applies compensation equal to coordinates is (x0−1, y1). 
       FIG. 2  shows an image  21  of the shape of the touched area of the thumb of a user, and an image  22  of the shape of the touched area of the forefinger of a user. In the embodiment, the image of the shape of the touched area of the finger is the image on the touch screen  20  of  FIG. 2  which reflects the actual touched portion of the touch screen  20 , by the finger of the user. 
       FIG. 3(   a ) shows an image of the shape of the touched areas of the right forefinger of a user when the key A, the key S, and the key Z are touched by the right forefinger of the user. The coordinates of the portions actually touched match the predetermined touch coordinates of the key A, the key S, and the key Z individually. In other words, the coordinates of the touch are exactly the predetermined touch coordinates; there is no offset in the touch.  FIG. 3(   b ) shows a different situation, when a user attempts to touch the key A, the key S, and the key Z. The touched coordinates do not match the predetermined touch coordinates of the key A, the key S, and the key Z respectively, and compensation has been applied, the actual touches have touch offset direction and touch offset distance relative to the predetermined touch coordinates. Under this condition, the touch control module  34  will compensate the touched coordinates of the touch with the touched coordinates as shown in  FIG. 3(   a ) according to the touch offset direction and touch offset distance of the finger of the user, as recorded in the calibration database  12 . 
     In the embodiment, the storage unit  10  further stores a calibration interface including a number of objects, such as virtual keys, touch icons and the like. When the touch calibration function of the electronic device  100  is activated by the user, the display control module  35  controls the touch screen  20  to display a dialog box to invite the user to do the touch calibration test. If the user selects to do the test, the display control module  35  further controls the touch screen  20  to display the calibration interface stored in the storage unit  10 , and controls a pop up dialog box to prompt the user to do the test in respect of the highlighted object. If the user confirms the test, eg. by selecting the icon “OK” displayed on the dialog box, the display control module  35  controls the objects displayed on the calibration interface to be highlighted in sequence according to a predetermined order. When the user touches the highlighted objects in sequence, the touch screen  20  generates signals in response to the touches on the object accordingly. The figure determination module  31  identifies and stores the image of the shape of the touched area of the finger of a user in the calibration database  12 . The calculation module  32  calculates the size of the touched area of the finger, and calculates the coordinates of the touch according to predefined arithmetic and the signals caused by the touch. The calculation module  32  further compares the coordinates of the actual touch and the predefined touch coordinates of the object, so as to determine the touch offset direction and the touch offset distance of the finger. The calculation module  32  further stores the calculated size of the shape of the touched area, the touch offset direction, the touch offset distance of the finger, in the calibration database  12 . The display control module  35  highlights the next object for guiding the user to progress through the test, until the user completes the test for all the objects displayed on the calibration interface. All of the calibration data of the user is stored in the calibration database  12 . 
       FIG. 4  shows a flowchart of a touch input control method of the electronic device  100  of  FIG. 1 . The electronic device  100  includes a touch screen and a storage unit. The touch screen generates signals in response to the user touches. The storage unit stores a calibration database  12  recording touch calibration data for fingers of a number of users. The touch calibration data of each finger includes the shape of the screen area in contact with a finger, the size of the touched area, the touch offset direction, and the touch offset distance, when the finger touches a single object. The touch offset direction is the offset direction of the touched point relative to the point having the predefined coordinates of the object which the user intends to touch. The touch offset distance is the offset distance between the touched point and the point having the predefined coordinates of the object which the user intends to touch. The method includes the following steps, each of which is related to the various components contained in the electronic device  100 : 
     In step S 41 , the display control module  35  controls the touch screen  20  to display an interface including a number of objects according to the command of a user. Each object is associated with predetermined touch coordinates. The object is a virtual key, or a touch icon or the like. 
     In step S 42 , the touch screen  20  generates signals in response to a touch on the touch screen  20  which is an attempt to touch an object. 
     In step S 43 , the calculation module  32  calculates coordinates of the actual touched portion on the touch screen  20  according to the generated signals. 
     In step S 44 , the determination module  33  determines whether the coordinates of the touch match the predetermined touch coordinates of one of the objects displayed on the touch screen  20 . If yes, the process ends, otherwise, the process goes to step S 45 . 
     In step S 45 , the determination module  33  creates an adjustment signal (touch compensation signal) and transmits the touch compensation signal to the touch control module  34 , the figure identification module  31 , and the calculation module  32 . 
     In step S 46 , the figure identification module  31  identifies the shape of the touched area on the touch screen  20  by the finger, and the calculation module  32  calculates the size of the touched area according to the signals from the touch screen  20 . In the embodiment, the calculation module  32  calculates the size of the touched area according to the resolution of the touch screen  20 , and the size of the touch screen  20 . 
     In step S 47 , the determination module  33  determines which finger it is which does the actual touching according to the shape of the touched area, the size of the touched area, and the touch calibration data of the user&#39;s commonly used finger, recorded in the calibration database  12 , and retrieves the touch offset direction and the touch offset distance of the determined finger of the user from the calibration database  12 . 
     In step S 48 , the touch control module  34  processes the coordinates of the touch of the user according to the retrieved touch offset direction and the retrieved touch offset distance of the determined finger, so as to determine the object which the user intended to touch. 
     With such a configuration, after the interface is displayed on the touch screen  20  in response to the operation of the user, if the coordinates of the touch by the user do not match with a predetermined touch coordinates of one of the objects displayed on the touch screen  20 , an adjustment signal is created, and the finger of the user touching the touch screen  20  is determined according to the shape of the touched area of the finger, the size of the touched area, and the touch calibration data of the user&#39;s commonly used finger recorded in the calibration database  12 . The touch offset direction and the touch offset distance of the determined finger of the user are also retrieved form the calibration database  12 , so as to apply compensation to the coordinates of the touch and to determine the touched object accordingly. Thus, the reliability and accuracy of the touch input is greatly improved. 
     Although the present disclosure has been specifically described on the basis of the embodiments thereof, the disclosure is not to be construed as being limited thereto. Various changes or modifications may be made to the embodiments without departing from the scope and spirit of the disclosure.