Patent Publication Number: US-2009237360-A1

Title: Virtual key input method

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority of Taiwanese application no. 097109863, filed on Mar. 20, 2008, which is incorporated herein by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a virtual key input method, more particularly to a virtual key input method that emulates a physical keyboard. 
     2. Description of the Related Art 
     A virtual keyboard, which emulates a physical keyboard, is commonly used in a mobile device equipped with a touch screen, such as a personal digital assistant (PDA) or a mobile phone. The touch screen may be of the capacitive type, the resistive type, or the wave type. However, since the conventional virtual keyboard has a reduced size compared to its counterpart physical keyboard, typing on the conventional virtual keyboard is error prone. 
     Two virtual keyboards have been proposed heretofore to address the aforementioned problem. In the first virtual keyboard  1 , as illustrated in  FIG. 1 , when a touch is detected on a key  11  thereof, the character  12  marked on the key  11  is displayed above the virtual keyboard  1  to indicate that a finger  10  is currently on the key  11 . In the second virtual keyboard  1 ′, as illustrated in  FIG. 2 , when a touch is detected on a key  11 ′ thereof, a window  12 ′, which shows the key  11 ′ and some other keys that surround the key  11 ′, is displayed above the virtual keyboard  1 ′. This, likewise, indicates that a finger is currently on the key  11 ′. 
     The two aforementioned conventional virtual keyboards  1 ,  1 ′ are disadvantageous in that, since the keys  11 ,  11 ′ thereof are too small and too close together, typing thereon is still error prone. 
     SUMMARY OF THE INVENTION 
     Therefore, an object of the present invention is to provide a virtual key input method that can overcome the aforesaid drawback of the prior art. 
     Another object of the present invention is to provide an electronic device that can overcome the aforesaid drawback of the prior art. 
     According to an aspect of the present invention, a virtual key input method comprises: 
     A) displaying a small virtual key that is marked with at least a first symbol; and 
     B) when a touch is detected on the small virtual key, displaying a large virtual key that is marked with a plurality of second symbols, that replaces the small virtual key, and that has a size larger than the small virtual key. 
     According to another aspect of the present invention, a virtual key input method comprises: 
     A) displaying a virtual key that is marked with a plurality of symbols; 
     B) detecting selection of one of the symbols on the virtual key; and 
     C) displaying the selected one of the symbols on the virtual key in a prominent manner. 
     According to yet another aspect of the present invention, an electronic device comprises a touch screen. The touch screen is operable so as to display a small virtual key that is marked with at least a first symbol, so as to detect a touch on the small virtual key, and so as to display a large virtual key that is marked with a plurality of second symbols, that replaces the small virtual key, and that has a size larger than the small virtual key. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, of which: 
         FIG. 1  is a schematic diagram illustrating a conventional virtual keyboard; 
         FIG. 2  is a schematic diagram illustrating another conventional virtual keyboard; 
         FIG. 3  is a block diagram of an embodiment of an electronic device equipped with a touch screen; 
         FIG. 4  is a flow chart of a embodiment of a virtual key input method to be implemented using the electronic device shown in  FIG. 3 ; 
         FIGS. 5 to 7  are schematic diagrams illustrating selection of a character on a virtual key in the embodiment shown in  FIG. 4 ; 
         FIG. 8  is a flow chart of another embodiment of a virtual key input method to be implemented using the electronic device shown in  FIG. 3 ; and 
         FIGS. 9 to 11  are schematic diagrams illustrating selection of a character on a virtual key in the embodiment shown in  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION 
     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. 
     An embodiment of an electronic device  2  is shown to include a processing unit  21 , a storage unit  22 , and a touch screen  23 . 
     The electronic device  2  may be a personal digital assistant (PDA), a smart phone, or a computer, such as a point of sale (POS) terminal. 
     The processing unit  21 , such as a central processing unit (CPU), is operable so as to run an operating system and so as to execute program instructions stored in the electronic device  2 . 
     The storage unit  22  is connected to the processing unit  21 . In this embodiment, the storage unit  22  is a memory device installed in the electronic device  2 . In other embodiments, the storage unit  22  may be a memory card, such as a Secure Digital (SD) memory card. 
     The touch screen  23 , such as a liquid crystal display (LCD) panel, includes a display module  232  and an input module  231 , each of which is connected to the processing unit  21 . 
     An embodiment of a virtual key input method to be implemented using the aforementioned electronic device  2  will now be described with further reference to  FIG. 4 . 
     In step  41 , with further reference to  FIG. 5 , the display module  232  of the touch screen  23  displays a plurality of small virtual keys  4 , each of which is marked with a plurality of first symbols  42 . 
     Since the small virtual keys  4  are identical in construction and operation, only one of the small virtual keys  4 , i.e., the key  41 , will be described herein. 
     In this embodiment, each of the first symbols  42  on the small virtual key  41  defines a first distance with an adjacent one of the first symbols  42  on the small virtual key  41 . Moreover, in this embodiment, each of the first symbols  42  on the small virtual key  41  is a character. 
     In step  42 , when the input module  231  of the touch screen  23  detects a touch, i.e., a finger  5  (see  FIG. 6 ), on the small virtual key  41 , the flow proceeds to step  43 . Otherwise, the flow goes back to step  41 . 
     In step  43 , with further reference to  FIG. 6 , the display module  232  of the touch screen  23  displays a large virtual key  41 ′ that is marked with a plurality of second symbols  42 ′, that replaces the small virtual key  41 , and that has a size larger than the small virtual key  41 . 
     In this embodiment, the large virtual key  41 ′ extends in a crosswise direction. Moreover, in this embodiment, the second symbols  42 ′ on the large virtual key  41 ′ are spacedly disposed along a lengthwise direction of the large virtual key  41 ′. Further, each of the second symbols  42 ′ on the large virtual key  41 ′ is identical to a respective one of the first symbols  42  on the small virtual key  41 . 
     Furthermore, in this embodiment, each of the second symbols  42 ′ on the large virtual key  41 ′ defines a second distance greater than the first distance with an adjacent one of the second symbols  42 ′ on the large virtual key  41 ′. The arrangement as such permits easier, faster, and accurate selection of each of the second symbols  42 ′ on the large virtual key  41 ′. 
     In another embodiment, the large virtual key  41 ′ extends in a lengthwise direction. 
     In step  44 , the input module  231  of the touch screen  23  detects selection of one of the second symbols  42 ′ on the large virtual key  41 ′. 
     As illustrated in  FIG. 7 , in this step, the selection of the second symbols  42 ′, e.g., the character “c”, on the large virtual key  41 ′ is detected when the input module  231  detects a touch on the second symbol  42 ′ on the large virtual key  41 ′ for a duration that exceeds a predetermined duration of, e.g., 0.5 seconds. 
     In some embodiments, in this step, the selection of the second symbols  42 ′ on the large virtual key  41 ′ is detected when the input module  231  detects a pressure exerted on the second symbol  42 ′ on the large virtual key  41 ′ exceeds a predetermined pressure. 
     In step  45 , when the input module  231  of the touch screen  23  detects the selection of one of the second symbols  42 ′ in step  44 , the flow proceeds to step  46 . Otherwise, the flow goes back to step  43 . 
     In step  46 , the display module  232  of the touch screen  23  displays the selected one of the second symbols  42 ′ on the large virtual key  41 ′ in a prominent manner. 
     This step may be performed by displaying in boldface, flashing, highlighting, or enclosing within a frame the selected one of the second symbols  42 ′ on the large virtual key  41 ′. 
     In step  47 , the display module  232  of the touch screen  23  executes a predefined action that corresponds to the selected one of the second symbols  42 ′ on the large virtual key  41 ′. That is, in some embodiments, since the selected one of the second symbols  42 ′ on the large virtual key  41 ′ is the character “c”, the display module  232  of the touch screen  23  displays the character “c”. 
     It is noted that the storage unit  22  stores first program instructions therein which when executed cause the electronic device  2  to perform the aforementioned virtual key input method. 
     Another embodiment of a virtual key input method to be implemented using the aforementioned electronic device  2  will now be described with further reference to  FIG. 8 . 
     In step  81 , with further reference to  FIG. 9 , the display module  232  of the touch screen  23  displays a plurality of small virtual keys  4 , each of which is marked with a first symbol  42 . 
     Since the small virtual keys  4  are identical in construction and operation, only one of the small virtual keys  4 , i.e., the key  41 , will be described herein. 
     In this embodiment, the first symbol  42  on the small virtual key  41  is a character. 
     In step  82 , when the input module  231  of the touch screen  23  detects a touch, i.e., a finger  5  (see  FIG. 10 ), on the small virtual key  41 , the flow proceeds to step  83 . Otherwise, the flow goes back to step  81 . 
     In step  83 , with further reference to  FIG. 10 , the display module  232  of the touch screen  23  displays a large virtual key  41 ′ that is marked with a plurality of second symbols  42 ′, that replaces the small virtual key  41 , and that has a size larger than the small virtual key  41 . 
     In this embodiment, the large virtual key  41 ′ extends in a crosswise direction. Moreover, in this embodiment, the second symbols  42 ′ on the large virtual key  41 ′ are spacedly disposed along a lengthwise direction of the large virtual key  41 ′. Further, one of the second symbols  42 ′, i.e., “K”, on the large virtual key  41 ′ is identical to the first symbol  42  on the small virtual key  41 . 
     Furthermore, in this embodiment, each of the second symbols  42 ′ on the large virtual key  41 ′ defines the second distance with an adjacent one of the second symbols  42 ′ on the large virtual key  41 ′. The arrangement as such permits easier, faster, and accurate selection of each of the second symbols  42 ′ on the large virtual key  41 ′. 
     In some embodiments, the large virtual key  41 ′ extends in a lengthwise direction. 
     In step  84 , the input module  231  of the touch screen  23  detects selection of one of the second symbols  42 ′ on the large virtual key  41 ′ 
     As illustrated in  FIG. 11 , in this step, the selection of the second symbol  42 ′, e.g., the character “M”, on the on the large virtual key  41 ′ is detected when the input module  231  detects a touch on the second symbol  42 ′ on the large virtual key  41 ′ for a duration that exceeds a predetermined duration, e.g., 0.5 seconds. 
     In some embodiments, in this step, the selection of the second symbols  42 ′ on the large virtual key  41 ′ is detected when the input module  231  detects a pressure exerted on the second symbol  42 ′ on the large virtual key  41 ′ exceeds a predetermined pressure. 
     In step  85 , when the input module  231  of the touch screen  23  detects the selection of one of the second symbols  42 ′ in step  84 , the flow proceeds to step  86 . Otherwise, the flow goes back to step  83 . 
     In step  86 , the display module  232  of the touch screen  23  displays the selected one of the second symbols  42 ′ on the large virtual key  41 ′ in a prominent manner. 
     This step is performed by displaying in boldface, flashing, highlighting, and enclosing within a frame the selected one of the second symbols  42 ′ on the large virtual key  41 ′. 
     In step  87 , the display module  232  of the touch screen  23  executes a predefined action that corresponds to the selected one of the second symbols  42 ′ on the large virtual key  41 ′. That is, in some embodiments, since the selected one of the second symbols  42 ′ on the large virtual key  41 ′ is the character “M”, the display module  232  of the touch screen  23  displays a name in a contact list that starts with the character “M”, e.g., “Mary”. 
     It is noted that the storage unit  22 , likewise, stores, second program instructions therein which when executed cause the electronic device to perform the aforementioned virtual key input method. 
     While the present invention has been described in connection with what are considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments 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.