Abstract:
A method of controlling a touch screen of an electronic device includes the following steps: switching the touch screen from a normal state into a shrunk state; and confining a touch interactive region of the touch screen to a sub-region of the touch screen and positioning a non-interactive region of the touch screen away from an edge of the touch screen to be partially covered by a finger performing an operation when the touch screen is in the shrunk state. The touch interactive region is a region within which the touch screen displays an interactive frame, and when the touch screen is in the normal state, the touch interactive region extends beyond the sub-region.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This continuation application claims the benefit of U.S. patent application Ser. No. 13/424,369, filed on Mar. 19, 2012, the contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates generally to a touch screen, and more particularly, to a method, device, and computer-readable medium for changing the size of a touch permissible region of a touch screen. 
         [0004]    2. Description of the Prior Art 
         [0005]    A touch screen is an electronic component that can display a frame of image and in the meantime detect the presence and location of a touch made by a living body. Because touch screens facilitate user-machine interaction that is not only convenient but also intuitive, they are widely applied in various kinds of electronic devices. 
         [0006]    Under some circumstances, a user may find the use of a touch screen less convenient. For example, the user of a large-screen smart phone maybe unable to reach some portion of the phone&#39;s touch screen if the user is holding the phone with only the right/left hand and manipulating the touch screen with only the right/left thumb. As another example, the user of a large-screen touch TV may find it difficult to reach some portion of the touch screen without taking one or a few steps. As still another example, a touch screen may have some dead points and as a result some interactions involving these dead points will become unavailable. 
       SUMMARY OF THE INVENTION 
       [0007]    It is therefore one objective of the present invention to provide a method, device and computer-readable medium for changing the size of a touch permissible region of a touch screen to solve the above problems. 
         [0008]    According to an embodiment of the present invention, an exemplary method of controlling a touch screen of an electronic device is disclosed. The exemplary method comprises the following steps: switching the touch screen from a normal state into a shrunk state; and confining a touch interactive region of the touch screen to a sub-region of the touch screen and positioning a non-interactive region of the touch screen away from an edge of the touch screen to be partially covered by a finger performing an operation when the touch screen is in the shrunk state. The touch interactive region is a region within which the touch screen displays an interactive frame, and when the touch screen is in the normal state, the touch interactive region extends beyond the sub-region. 
         [0009]    According to an embodiment of the present invention, an exemplary electronic device is disclosed. The exemplary electronic device comprises an input unit, a display unit and a processor. The processor is coupled to the input unit and the display unit, and arranged for switching the display unit from a normal state into a shrunk state. When the display unit is in the shrunk state, the processor confines an interactive region of the display unit to a sub-region of the display unit and positions a non-interactive region of the display unit away from a specific side of the display unit. The specific side of the display unit is determined in response to an input signal received by the input unit during or after the switching of the display unit. The interactive region is a region within which the display unit displays an interactive frame. When the display unit is in the normal state, the interactive region extends beyond the sub-region 
         [0010]    According to an embodiment of the present invention, an exemplary non-transitory computer-readable medium storing a computer program is disclosed. When executed by an electronic device comprising a touch screen, the exemplary non-transitory computer-readable medium causes the electronic device to perform the following operations: switching the touch screen from a normal state into a shrunk state; and confining a touch interactive region of the touch screen to a sub-region of the touch screen and positioning a non-interactive region of the touch screen away from an edge of the touch screen to be partially covered by a finger performing an operation when the touch screen is in the shrunk state. The touch interactive region is a region within which the touch screen displays an interactive frame, and when the touch screen is in the normal state, the touch interactive region extends beyond the sub-region. 
         [0011]    These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  shows a simplified block diagram of an electronic device according to an embodiment of the invention. 
           [0013]      FIG. 2  shows a schematic diagram of an exemplary setting of a sub-region of the touch screen of  FIG. 1 . 
           [0014]      FIG. 3  shows two schematic diagrams comparing how an interactive frame is displayed on the touch screen of  FIG. 1  in a normal and a shrunk state. 
           [0015]      FIG. 4  shows two schematic diagrams of the operating system (OS) program of the electronic device of  FIG. 1  when the touch screen of  FIG. 1  is in the normal and the shrunk states. 
           [0016]      FIG. 5  shows a flowchart of an exemplary method of controlling the touch screen of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0017]      FIG. 1  shows a simplified block diagram of an electronic device  100  according to an embodiment of the invention. As some examples, the electronic device  100  can be a smart phone, a tablet computer, a computer monitor, a personal digital assistant (PDA), a satellite navigation device, a handhold gaming device, or a television (TV). The electronic device  100  of this embodiment includes at least a processor  110 , a memory  120 , and a touch screen  130 . The touch screen  130  can be an integrated component or an external component of the electronic device  100 . 
         [0018]    The memory  120  stores codes of an operating system (OS) program and some application programs, and some other data. The processor  110  executes the OS program and the application programs to control the operations of the electronic device  100 . The touch screen  130  is an input/output (I/O) interface through which the electronic device  100  displays image frames to the user and receives touch instructions from the user. In addition to the three depicted components, the electronic device  100  can further include some other components, such as other components that interconnect or assist the interactions between the three depicted components, other I/O interfaces that allow the electronic device  100  to communicate with the outside world, and other components of other functions. These other components are omitted from  FIG. 1  to avoid distraction. 
         [0019]    The touch screen  130  has a touch permissible region, i.e. a region within which the touch screen  130  displays an interactive frame. The interactive frame is a frame of image that can contain one or more touchable portions at which the electronic device  100  is defined to be able to response to a touch operation made by a user of the electronic device  100 . In other words, when the user touches a touchable portion of the frame of image, the electronic device  100 , in response to the touch operation, is controlled to react to the user&#39;s input/touch. For example, a touchable portion can be a user-interface object such as an icon, a virtual button, or a virtual knob. As another example, a touchable portion can be a virtual writing/drawing pad on which the user can write/draw. An interactive frame needs not be entirely touchable. For example, an interactive frame can have a background image and at least one user-interface object overlaid thereon, wherein the background image can be a wall paper or a blank background. The portions of the interactive frame that are not occupied by the user-interface objects can be untouchable portions. For example, when the electronic device  100  is locked, an interactive frame displayed thereon may include an icon or an unlock image that occupies only a limited portion of the touch screen  130 . The rest of the interactive frame can be an untouchable portion and be either blank or occupied by a part of a background image. 
         [0020]    The touch screen  130  of this embodiment has a normal state and a shrunk state. For example, the shrunk state can be a special state of the touch screen  130 , under which the electronic device  100  confines the touch permissible region to a sub-region of the touch screen  130 . In addition, the normal state can be a default state of the touch screen  130 , under which the electronic device  100  allows the touch permissible region to extend beyond the sub-region. For example, when the touch screen  130  is in the normal state, the touch permissible region can coincide with a full-region of the touch screen  130 . 
         [0021]    When the touch screen  130  is in the shrunk state, the area outside the sub-region can be a blank area or be occupied by a part of a background image. If a background image exists in the area outside of the sub-region, the interactive frame displayed within the sub-region can be overlaid on the background image, like an on screen display (OSD). If a user touches the un-overlaid portion of the background image, the electronic device  100  does not respond to the user&#39;s touch. To put it differently, if the interactive frame is originally of the full size of the touch screen  130 , i.e. the size of the full-region, the electronic device  100  first shrinks the interactive frame into the size of the sub-region, then overlays the shrunk interactive frame on the background image to create the displayed image frame with a size of the full region of the touch screen  130 . The displayed image frame is displayed on the touch screen  130  so that the interactive frame, which has been shrunk already, is confined within the sub-region. 
         [0022]    If a frame to be displayed is not interactive in nature, e.g. the frame is a read-only image that contains no user-interface objects, no embedded hyperlinks, and no editable areas, the electronic device  100  can have the touch screen  130  display the frame in the full-region regardless of whether the touch screen  130  is in the normal or the shrunk state. For example, such a frame can be a video frame or, an image frame provided by a screensaver, a page of a plain electronic book, or a photo image. Alternatively, the electronic device  100  can have the touch screen  130  display the non-interactive frame in the full-region if the touch screen  130  is in the normal state and in the sub-region if the touch screen  130  is in the shrunk state. 
         [0023]    The user of the electronic device  100  can set whether the touch screen  130  can be switched between the normal state and the shrunk state. Furthermore, the electronic device  100  can be configured to allow the user to pre-set the orientation, location, and size of the sub-region and the conditions of switching.  FIG. 2  shows a schematic diagram of an exemplary setting of the sub-region of the touch screen  130  of  FIG. 1 . This example is based on the assumptions that the electronic device  100  is a handhold device, the user is right-handed, and the user sometimes holds the electronic device  100  with the right hand and manipulates the touch screen  130  with only the right thumb. In  FIG. 2 , the large rectangle represents the full-region of the touch screen  130 . When the user is holding the electronic device  100  with the right hand, the user&#39;s right thumb is able to reach the region on right side of the touch screen  130  defined by a broken curve, but is unable to reach the region on the left side of the touch screen  130  defined by the broken curve. The user&#39;s left hand may be unavailable in the meantime, e.g. because it is holding/grabbing another thing such as an umbrella, a handbag, or a handrail. To facilitate one hand manipulation of the touch screen  130 , the user can pre-set the sub-region so that it&#39;s on the lower right corner of the full-region, and to the extent the upper left corner of the sub-region is on the broken curve or on the right side of the broken curve. The electronic device  100  may require the user to pre-set the sub-region only once or set the sub-region every time the user wants to switch the touch screen  130  from the normal state to the shrunk state. 
         [0024]      FIG. 3  shows two schematic diagrams comparing how an interactive frame is displayed on the touch screen  130  of  FIG. 1  in the normal and shrunk states. Regardless of how the shrunk state is realized, in the shrunk state the perception of the user may be that an interactive frame has been shrunk from the size of the full-region into the size of the sub-region and placed within the sub-region. If the user is holding the electronic device  100  with the right hand and manipulating the touch screen  130  with only the right thumb, the user can reach all the virtual buttons displayed on the touch screen  130  when it&#39;s in the shrunk state. In contrast, if the touch screen  130  is in the normal state, the user&#39;s right thumb won&#39;t be able to reach the virtual button of number 1. As a result, confining the interactive frame within the sub-region can facilitate the user&#39;s one hand manipulation of the touch screen  130 . 
         [0025]    As shown in  FIG. 3 , a point displayed on coordinates (x, y) when the touch screen  130  is in the normal state will instead be displayed on coordinates (x′, y′) when the touch screen  130  in the shrunk state. The coordinates (x, y) lies within a normal coordinate system defined by four corner points (x1, y1), (x2, y1), (x1, y2), and (x2, y2). The normal coordinate system corresponds to the full-region of the touch screen  130 ; (x2−x1) and (y2−y1) are equal to the width W and height H of the full-region, respectively. The coordinates (x′, y′) lies within a shrunk coordinate system defined by four corner points. (x1′, y1′), (x2′, y1′), (x1′, y2′), and (x2′, y2′) The shrunk coordinate system corresponds to the sub-region of the touch screen  130 ; (x2′−x1′) and (y2′−y1′) are equal to the width W′ and height H′ of the sub-region, respectively. For example, in  FIG. 3 , the corner points (x2, y2) and (x2′, y2′) are on the same location of the touch screen  130 . In other words, x2 equals to x2′, and y2 equals to y2′. 
         [0026]    If the OS program of the electronic device  100  is designed to support touch screens with different sizes, in the shrunk state the electronic device  100  can disable the pixels outside the sub-region, treat the touch screen  130  as if the sub-region constitutes a full-region, and drive the touch screen  130  accordingly. For example, if the size of the touch screen is 4.2 inches and the size of the sub-region is 3.2 inches and the OS program supports both 4.2-inch and 3.2-inch touch screens, in the shrunk state the electronic device  100  can confine an interactive frame within the sub-region by driving the touch screen  130  as if it&#39;s a 3.2-inch touch screen. 
         [0027]    As an alternative, in the shrunk state the OS program can performs coordinate transformation in order to transform a pair of coordinates (x, y) on the normal coordinate system into a pair of corresponding coordinates (x′, y′) on the shrunk coordinate system, and vice versa.  FIG. 4  shows two schematic diagrams of the OS program of the electronic device  100  when the touch screen  130  is in the normal and shrunk states. The OS program has an OS kernel  410  that is responsible for, among other duties, providing core system services and interacting with a touch sensor input module  420 , a screen output module  430 , and a remaining part  440  of the OS program. The touch sensor input module  420  can be a driver that drives the touch screen  130  to detect touches; the screen output module  430  can be a driver that drives the touch screen  130  to display frames of images successively. 
         [0028]    When the touch screen  130  is in the normal state, the OS kernel  410 , the touch sensor input module  420 , and the screen output module  430  all uses the normal coordinate system and there may be no need for coordinate transformation. When the touch screen  130  is in the shrunk state, the OS kernel  410  can keep using the normal coordinate system but in effect the touch sensor input module  420  and the screen output module  430  use the shrunk coordinate system instead. As a result, when the touch screen  130  is in the shrunk state, the OS program can further include a mapping module  450  for transforming each point (x, y) on the normal coordinate system into a corresponding point (x′, y′) on the shrunk coordinate system, and vice versa. 
         [0029]    Specifically, the mapping module  450  transforms display coordinates from the normal coordinate system to the shrunk coordinate system. For example, when the OS kernel  410  wants a pixel to be displayed on point (x, y) of the normal coordinate system, the mapping module  450  will transform the location into (x′, y′) on the shrunk coordinate system so that the screen output module  430  can drive the touch screen  130  to display that pixel on point (x′, y′). In effect, the mapping module  430  shrinks an interactive frame from the size of the full-region into the size of the sub-region and confines the shrunk interactive frame to the sub-region. Using  FIG. 3  as an example, the coordinate transformation can be performed based on the following equations: 
         [0000]        x′ =( x−x 1)·( W′/W )+ x 1′
 
         [0000]        y′ =( y−y 1)·( H′/H )+ y 1′
 
         [0030]    Furthermore, the mapping module  450  transforms touch sensor coordinates from the shrunk coordinate system to the normal coordinate system. For example, when the touch screen  130  informs the touch sensor input module  420  that a touch has been detected on point (x′, y′), the mapping module  450  will transform the location into (x, y) on the normal coordinate system and inform the OS kernel  410  a touch has been detected on point (x, y). Using  FIG. 3  as an example, the coordinate transformation can be performed based on the following equations: 
         [0000]        x =( x′−x 1′)·( W/W ′)+ x 1
 
         [0000]        y =( y′−y 1′)·( H/H′ )+ y 1
 
         [0031]      FIG. 5  shows a flowchart of an exemplary method of controlling the touch screen  130 . At step  510 , the electronic device  100  first determines whether a set of condition(s) for switching the touch screen  130  from the normal state to the shrunk state is satisfied. If the set of condition(s) is not satisfied, the electronic device  100  enters step  520 ; otherwise, the electronic device  100  enters step  530 . 
         [0032]    For example, the set of condition(s) may include: (1) the user has activated the screen-shrink function (so that the touch screen  130  is allowed to be switched from the normal state to the shrunk state) ; and (2) the electronic device  100  has detected a trigger event. If the electronic device  100  is a handhold device, the detection of the trigger event may indicate that the user is holding and manipulating the electronic device  100  with only one hand. For example, the trigger event may be that the user unlocks the electronic device  100  with a first gesture. In such an example, whenever the electronic device  100  is locked, the electronic device  100  may allow the user to use either the first or a second unlock gesture to unlock the electronic device  100 . The first unlock gesture allows the user to unlock the electronic device  100  and switch the touch screen  130  to the shrunk state. The second unlock gesture allows the user to unlock the electronic device  100  and maintain the touch screen  130  at the normal state. 
         [0033]    As another example, the trigger event may be that the orientation of the electronic device  100  lies within a specific range when the user turns on the electronic device  100  or unlocks electronic device  100 . In such an example, the electronic device  100  needs to have an electronic gyroscope, e.g. MEMS gyroscope, or 3D accelerometers in order to determine the orientation. Furthermore, the user may need to pre-set the specific range. One of the rationales behind this example is that the detected orientation may indicate whether the user is holding the electronic device  100  with only one hand or with both hands. In still another example, the trigger event is that the user specifically instructs the electronic device  100  to switch the touch screen  130  to the shrunk state. 
         [0034]    At step  520 , the electronic device  100  controls the touch screen  130  at the normal state and allows the full-region of the touch screen  130  to serve as the touch permissible region. Specifically, the electronic device  100  maintains the touch screen  130  in the normal state if it&#39;s already in the normal state or switches the touch screen  130  to the normal state if it&#39;s in the shrunk state. Since the normal state can be a default state of the touch screen  130 , when the touch screen  130  is in this state, the electronic device  100  may drive it normally without performing other additional/special operations. For example, when the touch screen  130  is in the normal state, the electronic device  100  may display an interactive frame on the full-region of the touch screen  130  without first shrinking the interactive frame. 
         [0035]    At step  530 , the electronic device  100  controls the touch screen  130  at the shrunk state and confines the touch permissible region to the sub-region. Specifically, the electronic device  100  switches the touch screen  130  to the shrunk state if it&#39;s in the normal state or maintains the touch screen  130  in the shrunk state if it&#39;s already in the shrunk state. Since the shrunk state can be a special state of the touch screen  130 , when the touch screen  130  is in this state, the electronic device  100  may need to perform some additional/special operations. For example, as mentioned above, the electronic device  100  can treat the sub-region as a full-region of the touch screen  130 , and drive the touch screen  130  accordingly. As another example, the electronic device  100  can perform coordinate transformation in order to confine a displayed interactive frame within the sub-region. 
         [0036]    At step  540 , the electronic device  100  determines whether another set of condition(s) for switching the touch screen  130  from the shrunk state to the normal state is satisfied. If the set of condition(s) is not satisfied, the electronic device  100  returns to step  530 ; otherwise, the electronic device  100  enters step  520 . 
         [0037]    The set of condition(s) may include the detection of a trigger event. For example, the trigger event may be that the electronic device  100  has been locked, whether automatically or manually. As another example, the trigger event may be that the user unlocks the electronic device  100  using the second one of the aforementioned two unlock gestures. In a third example, the trigger event may be that the orientation of the electronic device  100  does not lie within the aforementioned specific range when the user turns on the electronic device  100  or unlocks the electronic device  100 . In a fourth example, the trigger event is that the user specifically instructs the electronic device  100  to switch the touch screen  130  to the normal state, e.g. by manipulating (such as touching) a screen-expansion image displayed on the touch screen  130  when it&#39;s in the shrunk state. To facilitate the fourth example, the electronic device  100  can control the touch screen  130  to additionally display the screen-expansion image whenever the touch screen  130  is in the shrunk state. 
         [0038]    The aforementioned shrunk state can facilitate the user&#39;s use the touch screen  130 . For example, the shrunk state can make the use more convenient if the electronic device  100  is a large-screen smart phone that the user is holding with only the right/left hand and manipulating with only the right/left thumb. As another example, the shrunk state can make the use more convenient if the electronic device  100  is a large-screen touch TV and the user wants to stand still in using the touch screen  130 . As still another example, the shrunk state can make the use more convenient if the touch screen  130  has some dead points and it happens that the user needs to use some of the dead points to interact with the electronic device  100 . Specifically, the shrunk state allows a user-interface object of interest to the user to be relocated from a dead point to a normal point of the touch screen  130 . 
         [0039]    Any of the aforementioned control methods, or any combination thereof, can be codified into a computer program. The computer program can be stored in a computer readable medium, such as the memory  120  shown in  FIG. 1 . When being executed by the processor  110 , the computer program can cause the electronic device  100  to perform the codified method (s). 
         [0040]    Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.