Abstract:
A touch control module includes a touch control unit operable so as to generate a contact signal in response to contact with an object, a computing unit coupled electrically to the touch control unit so as to receive the contact signal therefrom, and a transmission interface including a set of transmission lines coupled electrically to the computing unit. The computing unit is configured to generate different control signals, each of which is generated in accordance with a contact position of the object with the touch control unit. Each of the transmission lines is used to transmit a respective one of the control signals to a host unit for scrolling control of a graphical user interface display of the host unit.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims priority of Chinese Appln. No. 200310121521.4, filed on Dec. 19, 2003.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The invention relates to a touch control module for electronic devices, more particularly to a touch control module that can simplify decoding of control signals generated thereby.  
         [0004]     2. Description of the Related Art  
         [0005]      FIG. 1  illustrates a conventional graphical user interface (GUI) display  9  of a computer. The GUI display  9  has a data display portion  91 , and vertical and horizontal scroll bars  92 ,  93  respectively disposed on vertical and horizontal edges of the data display portion  91  for scrolling control of an image shown on the latter. A pointing device (not shown) , such as a mouse or a track ball, is operated for moving a cursor  8  over a selected one of the scroll bars  92 ,  93  when it is desired to scroll the image shown on the data display portion  91  in the vertical or horizontal direction. However, because the sizes of the scroll bars  92 ,  93  are relatively small so as to maximize the size of the display area of the data display portion  91 , it is difficult and inconvenient for the user to perform image scrolling control through exact positioning of the cursor  8  on the selected scroll bar  92 ,  93 .  
         [0006]     In order to overcome the above drawback, U.S. Pat. No. 5,943,052 discloses an apparatus for touchpad-based scroll control that includes a data packet processor working in conjunction with a touchpad. The touchpad is defined with a scroll zone. When the touchpad is operated along the length of the scroll zone, corresponding data packets are generated and are processed by the data packet processor for subsequent control of scrolling of the contents of a data display portion of a GUI display of an electronic device.  
         [0007]     In the aforesaid U.S. patent, the data packet processor receives data packets through a transmission line. Hence, the data packet processor requires a relatively complicated decoding scheme for deciphering the operation intended by the user. The complexity of the decoding scheme is further increased when tap-and-drag, single-tap, and double-tap operations are to be considered as well.  
       SUMMARY OF THE INVENTION  
       [0008]     Therefore, the object of the present invention is to provide a touch control module for electronic devices that can simplify decoding of control signals generated thereby.  
         [0009]     Another object of the present invention is to provide an electronic device that includes the touch control module of this invention.  
         [0010]     According to one aspect of the invention, a touch control module comprises:  
         [0011]     a touch control unit operable so as to generate a contact signal in response to contact with an object;  
         [0012]     a computing unit coupled electrically to the touch control unit so as to receive the contact signal therefrom, the computing unit being configured to generate different control signals, each of which is generated in accordance with a contact position of the object with the touch control unit; and  
         [0013]     a transmission interface including a set of transmission lines coupled electrically to the computing unit, each of the transmission lines being used to transmit a respective one of the control signals.  
         [0014]     The transmission interface is adapted to provide the control signals to a host unit for scrolling control of a graphical user interface display of the host unit.  
         [0015]     According to another aspect of the invention, an electronic device comprises:  
         [0016]     a host unit including an operating system and a graphical user interface (GUI) display having a scroll bar feature and operably associated with the operating system;  
         [0017]     a touch control unit operable so as to generate a contact signal in response to contact with an object;  
         [0018]     a computing unit coupled electrically to the touch control unit so as to receive the contact signal therefrom, the computing unit being configured to generate different control signals, each of which is generated in accordance with a contact position of the object with the touch control unit; and  
         [0019]     a transmission interface including a set of transmission lines interconnecting electrically the computing unit and the host unit, each of the transmission lines being used to transmit a respective one of the control signals to the host unit.  
         [0020]     The operating system of the host unit is responsive to the control signal received from the transmission interface for scrolling control of the GUI display. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]     Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which:  
         [0022]      FIG. 1  illustrates a conventional graphical user interface (GUI) display with a scroll bar feature;  
         [0023]      FIG. 2  is a schematic circuit block diagram of an electronic device that incorporates the preferred embodiment of a touch control module according to the present invention;  
         [0024]      FIG. 3  is a schematic view to illustrate one example of a touch control unit for the touch control module of  FIG. 2 ;  
         [0025]      FIG. 4  is a schematic view to illustrate another example of a touch control unit for the touch control module of  FIG. 2 ;  
         [0026]      FIG. 5  illustrates how operation of the touch control unit of  FIG. 3  can result in scrolling of a GUI display of the electronic device;  
         [0027]     FIGS.  6 ( a ) and  6 ( b ) are sample control signals provided by the touch control module to an operating system in the electronic device of  FIG. 2 ;  
         [0028]      FIG. 7  is a schematic view to illustrate still another example of a touch control unit for the touch control module of  FIG. 2 ; and  
         [0029]      FIG. 8  is a schematic view to illustrate yet another example of a touch control unit for the touch control module of  FIG. 2 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0030]     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.  
         [0031]     Referring to  FIG. 2 , the preferred embodiment of a touch control module  4  according to the present invention is used in conjunction with a host unit  5  of an electronic device. The host unit  5  includes an operating system  51  and a graphical user interface (GUI) display  52  having a scroll bar feature and operably associated with the operating system  5  in a conventional manner.  
         [0032]     The touch control module  4  includes a touch control unit  41 , a computing unit  42  coupled electrically to the touch control unit  41 , and a transmission interface  43 . In this embodiment, the transmission interface  43  includes first, second, third and fourth transmission lines  431 ,  432 ,  433 ,  434 , each of which has a first end connected electrically to the computing unit  42 , and a second end connected electrically to the host unit  5 . Each of the first, second, third and fourth transmission lines  431 ,  432 ,  433 ,  434  is used to transmit a corresponding control signal from the computing unit  42  for reception by the host unit  5 .  
         [0033]     In use, when an object (not shown) contacts the touch control unit  41 , a contact signal  100  is generated by the touch control unit  41  and is provided to the computing unit  42 . Based on contact position of the object with the touch control unit  41 , the computing unit  42  generates a corresponding control signal  200 . In this embodiment, the different control signals  200  generated by the computing unit  42  include a first control signal  201 , a second control signal  202 , a third control signal  203 , and a fourth control signal  204 , which are transmitted to the host unit  5  via a respective one of the first, second, third and fourth transmission lines  431 ,  432 ,  433 ,  434  of the transmission interface  43 .  
         [0034]      FIG. 3  illustrates one example of the touch control unit  41  for the touch control module  4 . In the example of  FIG. 3 , the touch control unit  41 , which is in the form of any known resistive, capacitive or light-sensitive touch control device, is defined with a first contact region  411 , a second contact region  412 , a third contact region  413 , and a fourth contact region  414 . The first and second contact regions  411 ,  412  are in the form of strips that extend along parallel first and second axes (a, b), respectively. The third and fourth contact regions  413 ,  414  are in the form of strips that extend respectively along parallel third and fourth axes (c, d) transverse to the first and second axes (a, b) . In the touch control unit  41  of  FIG. 3 , the first, second, third and fourth contact regions  411 ,  412 ,  413 ,  414  cooperate to form a closed rectangular loop.  
         [0035]      FIG. 4  illustrates another example of the touch control unit  41  for the touch control module  4 . In the example of  FIG. 4 , the touch control unit  41 , which is in the form of any known resistive, capacitive or light-sensitive touch control device, is similarly defined with a first contact region  411 , a second contact region  412 , a third contact region  413 , and a fourth contact region  414 . The first and second contact regions  411 ,  412  are interconnected at one end and extend along a first axis (e). The third and fourth contact regions  413 ,  414  are interconnected at one end and extend along a second axis (f) transverse to the first axis (e). In the touch control unit  41  of  FIG. 4 , the third and fourth contact regions  413 ,  414  are connected to the interconnected ends of the first and second contact regions  411 ,  412  such that the first, second, third and fourth contact regions  411 ,  412 ,  413 ,  414  cooperate to form a cross-shaped configuration.  
         [0036]     It should be noted herein that the object can be used to perform tap-and-drag, single-tap and double-tap operations on the touch control unit  41 . Moreover, the specific arrangement of the first, second, third and fourth contact regions  411 ,  412 ,  4113 ,  413 ,  414  of the touch control unit  41  may be altered to suit the intended application.  
         [0037]     Referring to  FIGS. 2, 3  and  5 , each of the first, second, third and fourth contact regions  411 ,  412 ,  413 ,  414  is formed with parallel scan lines that are transverse to the axis (a, b, c, d) of the respective contact region  411 ,  412 ,  413 ,  414 . Hence, movement of the object along each of the first, second, third and fourth contact regions  411 ,  412 ,  413 ,  414  can be sensed to result in generation of the corresponding contact signal  100 .  
         [0038]     Referring again to  FIGS. 2 and 3 , when a contact signal  100  due to contact of the object with the first contact region  411  is received by the computing unit  42 , the computing unit  42  generates the first control signal  201  that is transmitted to the host unit  5  via the first transmission line  431 . When a contact signal  100  due to contact of the object with the second contact region  412  is received by the computing unit  42 , the computing unit  42  generates the second control signal  202  that is transmitted to the host unit  5  via the second transmission line  432 . When a contact signal  100  due to contact of the object with the third contact region  413  is received by the computing unit  42 , the computing unit  42  generates the third control signal  203  that is transmitted to the host unit  5  via the third transmission line  433 . When a contact signal  100  due to contact of the object with the fourth contact region  414  is received by the computing unit  42 , the computing unit  42  generates the fourth control signal  204  that is transmitted to the host unit  5  via the fourth transmission line  434 . It should be noted therein that the control signal  200  generated by the computing unit  42  is preferably a pulse signal, such as the square wave pulse signal of  FIG. 6 ( a ) or the impulse signal of  FIG. 6 ( b ), that contains displacement information of the object on the touch control unit  41 . Preferably, the control signal  200  contains a number of pulses that corresponds to the number of scan lines crossed by the object when the latter moves along the corresponding contact region  411 ,  412 ,  413 ,  414  of the touch control unit  41 .  
         [0039]     When the operating system  51  of the host unit  5  receives the control signal  200 , an intended scrolling distance (such as in units of line, block or page) for the GUI display  52  of the host unit  5  is determined by the operating system  51  based on the displacement information contained in the control signal  200 . In the preferred embodiment, the first control signal  201  corresponds to upward scrolling control for the GUI display  52 , the second control signal  202  corresponds to downward scrolling control for the GUI display  52 , the third control signal  203  corresponds to left-hand scrolling control for the GUI display  52 , and the fourth control signal  204  corresponds to right-hand scrolling control for the GUI display  52 . With reference to  FIGS. 2, 3  and  5 , when an object is used to perform a tap-and-drag operation on the fourth contact region  414 , the computing unit  42  receives the corresponding contact signal  100  from the touch control unit  41 , and generates the fourth control signal  204  that is transmitted to the host unit  5  via the fourth transmission line  434 . In response to the fourth control signal  204 , the operating system  51  calculates a moving distance (Δd) for a first scroll bar  521  of the GUI display  52  corresponding to the displacement (Δx) of the object on the fourth contact region  414  of the touch control unit  41 .  
         [0040]     A second scroll bar  522  of the GUI display  52  is controlled in a substantially similar manner. Particularly, when an object is used to perform a tap-and-drag operation on the first (or second) contact region  411  ( 412 ), the computing unit  42  receives the corresponding contact signal  100  from the touch control unit  41 , and generates the first (or second) control signal  201  ( 202 ) that is transmitted to the host unit  5  via the first (or second) transmission line  431  ( 432 ). In response to the first (or second) control signal  201  ( 202 ), the operating system  51  calculates a moving distance for the second scroll bar  522  of the GUI display  52  corresponding to the displacement of the object on the first (or second) contact region  411  ( 412 ) of the touch control unit  41 .  
         [0041]      FIG. 7  illustrates still another example of the touch control unit  41  for the touch control module  4 . In the example of  FIG. 7 , the touch control unit  41 , which is in the form of any known resistive, capacitive or light-sensitive touch control device, is defined with a first contact region  415  and a second contact region  416 . The first contact region  415  is in the form of a strip that extends along a first axis (g). The second contact region  416  is in the form of a strip that extends along a second axis (h) transverse to the first axis (g). One end of the first contact region  415  intersects an intermediate portion of the second contact region  416 . The first contact region  415  is formed with parallel scan lines that are transverse to the first axis (g). On the other hand, the second contact region  416  is formed with parallel scan lines that are transverse to the second axis (h).  
         [0042]     When a contact signal  100  due to movement of an object along the first contact region  415  in a first (upward) direction is received by the computing unit  42 , the computing unit  42  generates the first control signal  201  that is transmitted to the host unit  5  via the first transmission line  431 . When a contact signal  100  due to movement of the object along the first contact region  415  in a second (downward) direction is received by the computing unit  42 , the computing unit  42  generates the second control signal  202  that is transmitted to the host unit  5  via the second transmission line  432 . When a contact signal  100  due to movement of the object along the second contact region  416  in a third (left) direction is received by the computing unit  42 , the computing unit  42  generates the third control signal  203  that is transmitted to the host unit  5  via the third transmission line  433 . When a contact signal  100  due to movement of the object along the second contact region  416  in a fourth (right) direction is received by the computing unit  42 , the computing unit  42  generates the fourth control signal  204  that is transmitted to the host unit  5  via the fourth transmission line  434 .  
         [0043]      FIG. 8  illustrates yet another example of the touch control unit  41  for the touch control module  4 . In the example of  FIG. 8 , the touch control unit  41 , which is in the form of any known resistive, capacitive or light-sensitive touch control device, is defined with first and second contact regions  418 ,  419  (similar to the first and second contact regions  411 ,  412  of  FIG. 3 ), and a third contact region  417  (similar to the second contact region  416  of  FIG. 7 ).The third contact region  417  extends transverse to the first and second contact regions  418 ,  419 , and is connected to the first and second contact regions  418 ,  419  at opposite ends thereof. In the example of  FIG. 8 , the first, second and third contact regions  418 ,  419 ,  417  cooperate to form a U-shaped configuration.  
         [0044]     In the touch control module  4  of this invention, the different control signals  201 ,  202 ,  203 ,  204  are transmitted to the host unit  5  via the different transmission lines  431 ,  432 ,  433 ,  434  of the transmission interface  43 , respectively. In addition, because the control signals  201 ,  202 ,  203 ,  204  are in the form of pulse signals, the operating system  51  of the host unit  5  can easily decode the same so as to achieve the intended scrolling operation for the GUI display  52  without the need to perform complex packet transmission and decoding operations.  
         [0045]     While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment 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.