Abstract:
An apparatus for character input is disclosed. The apparatus includes a keypad and a processing unit. The keypad comprises a plurality of combo keys. Each combo key includes a main contact and at least one sub-contact adjacent to the main contact, the main contact and the sub-contact respectively have at least one icon representing a character. The processing unit receives a press operation on the keypad and inputting a corresponding character. The keypad of the apparatus is compact in size while character input on the keypad is conveniently.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to an apparatus and a method for character input.  
         [0003]     2. Description of Related Art  
         [0004]     Hand-held devices with text input capabilities have become more and more popular. These devices, for example, mobile phones and personal digit assistants, usually adopt a keypad for character input function. The keypad typically has fewer keys than a QWERTY keyboard. Several characters are arranged on a single key of the keypad. For example, a single key represents a number and two or three characters at the same time. Inputting characters on the keypad is time consuming. A user usually needs to operate keys a plurality of times to input one character.  
         [0005]     Therefore, what is needed is an apparatus for rapid character input using a new kind of keypad.  
       SUMMARY OF THE INVENTION  
       [0006]     An apparatus for character input is disclosed. The apparatus includes a keypad and a processing unit. The keypad comprises a plurality of combo keys. Each combo key includes a main contact and at least one sub-contact adjacent to the main contact. The main contact and the sub-contact respectively have at least one icon representing a character. The processing unit receives a press operation on the keypad and inputting a corresponding character.  
         [0007]     A method for character input which is used in an electronic device is disclosed. The method comprising the steps of: a) Providing a key board. The keypad includes a plurality of combo keys. Each combo key includes a main contact and at least one sub-contact adjacent to the main contact. The main contact and the sub-contact respectively have at least one icon representing a character. b) Depressing a combo key. c) Inputting a corresponding character.  
         [0008]     Further features and advantages will be provided or will become apparent in the course of the following detailed description. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]      FIG. 1  is a schematic, front view of an electronic device with a keypad according to a first preferred embodiment of the present invention;  
         [0010]      FIG. 2  is a schematic diagram of a hardware infrastructure of the electronic device of  FIG. 1 ;  
         [0011]      FIG. 3  is a schematic, front view of the keypad of  FIG. 1 ;  
         [0012]      FIG. 4  is a schematic, isometric view of a combo key of  FIG. 3 ;  
         [0013]      FIG. 5  is a cross section view of  FIG. 4 ;  
         [0014]      FIG. 6  is a flowchart of a preferred method of character input used in the electronic device of  FIG. 1 ; and  
         [0015]      FIG. 7  is a schematic, front view of a keypad according to a second preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0016]     Referring to  FIGS. 1 and 2 , an electronic device  30  with a keypad  10  according to a first preferred embodiment of the present invention is disclosed. The electronic device  30  includes the keypad  10 , a display  31 , a processing unit  32 , and a power supply  33 . The keypad  10  is for inputting characters. The processing unit  32  receives an input from the keypad  10  and displays a corresponding character on the display  31 .  
         [0017]     Referring to  FIGS. 3, 4 , and  5 , the keypad  10  and combo keys  15  thereof are disclosed. The keypad  10  includes four key rows  11 ,  12 ,  13 ,  14 . Each key row includes three combo keys  15 . Each combo key  15  includes a main contact  110 , and two sub-contacts  111 ,  112 . The two sub-contacts  111 ,  112  are on opposite sides of the main contact  110 .  
         [0018]     Each main contact  110  of the key rows  11 ,  12 ,  13 ,  14  has a relatively large primary icon indicating a unique member of a first subset of a character set. The character set is the set of characters found on a typical keyboard. In the first preferred embodiment the first subset of a character set includes the number set, a predetermined symbol, and the space symbol, such as that shown in  FIG. 2 . Each main contact  110  of the key rows  11 , 12 ,  13  and each sub-contact  111  or  112  of the key rows  11 ,  12 ,  13 ,  14  also has a secondary icon indicating a unique member of a second subset of the character set. In the first preferred embodiment, the second subset includes the English alphabet and punctuation symbol, such as that shown in  FIG. 2 .  
         [0019]     A main contact  16  and a sub-contact  17  of key row  14  are respectively designated as a function key for switching between a first input mode and a second input mode. In this embodiment, the first input mode is the number input mode, and the second input mode is the letter input mode. In the number input mode, the main contact  110  of the key rows  11 ,  12 ,  13 ,  14  are employed to input the primary icon (i.e., the number) indicated. In the second input mode, the main contact  110  of the key rows  11 ,  12 ,  13  are employed to input the secondary icon indicated.  
         [0020]     Each combo key  15  of the keypad is further connected to a rubber pin  113 . The rubber pin  113  includes touch points  130 ,  131 ,  132 , corresponding to the main contact  110 , the sub-contact  111 , and the sub-contact  112  respectively. A depression of the main contact  110 , the sub-contact  111 , or the sub-contact  112  triggers the touch point  130 ,  131 ,  132  to electrically connect with an inner circuit (not shown) of the electronic device  30  correspondingly.  
         [0021]     The main contact  110  and the sub-contacts  111 ,  112  can be depressed together or independently. When the main contact  110  is depressed, the processing unit  32  is programmed to accept the input from the main contact  110 , and displays the character on the display  31  as depicted by the symbol on the main contact  110 . When sub-contact  111  or when a combination of sub-contact  111  and the main contact  110  is/are depressed, the processing unit  32  is programmed to accept the input from the sub-contact  111  and displays the character on the display  31  as depicted by the symbol on the sub-contact  111 . Similarly, when sub-contact  112  or when a combination of sub-contact  112  and the main contact  110  is/are depressed, the processing unit  32  is programmed to accept the input from the sub-contact  112  and displays the character on the display  31  as depicted by the symbol on the sub-contact  112 .  
         [0022]     Referring to  FIG. 6 , a method of character inputs in the electronic device  30  is disclosed. When the character input procedure is started, in step S 40 , the electronic device  30  defaults to the first input mode then goes to step S 41 . In step S 41 , the electronic device  30  receives input signal from a combo key  15 , then goes to step S 42 . In step S 42 , the electronic device  30  detects whether the function key  16 ,  17  is depressed. If the function key  16  or the function key  17  is depressed, goes to step S 45 ; else, goes to step S 43 . In step S 43 , the electronic device  30  detects whether the main contact  110  of the combo key  15  is depressed. If the main contact  110  is depressed, goes to step S 44 , else, goes to step S 41 . In step S 44 , the electronic device  30  displays the primary icon (i.e., the number) indicated by the main contact  110  on the display  31 , then goes to step S 41 . In step S 45 , the electronic device  30  shifts to the second input mode, then goes to step S 46 . In step S 46 , the electronic device  30  receives input signal from a combo key  15 , then goes to step S 47 . In step S 47 , the electronic device  30  detects whether the function key  16 ,  17  is depressed. If the function key  16  or the function key  17  is depressed, goes to step S 40 ; else, goes to step S 48 . In step S 48 , the electronic device  30  detects whether the sub-contact  111  or the sub-contact  12  is depressed. If the sub-contact  111  or the sub-contact  12  is depressed, goes to step S 50 ; else goes to step S 49 . In step S 49 , the electronic device  30  displays the secondary icon (i.e., the alphabet letter) indicated by the main contact  110  on the display  31 , then goes to step S 46 . In step S 50 , the electronic device  30  displays the secondary icon (i.e., the alphabet letter) indicated by the sub-contact  111  or the sub-contact  112  on the display  31 , then goes to step S 46 .  
         [0023]     Referring to  FIG. 7 , another embodiment of a keypad used in the electronic device  30  is disclosed. The keypad  20  includes four key rows  21 ,  22 ,  23 ,  24 . Each key row includes three combo keys  25 . Each combo key  25  includes a main contact  210  and two sub-contacts  211 ,  212 . The two sub-contacts  211 ,  212  are connected to each other and further enclose a main contact of the combo key. Other features of the keypad  20  are similar to keypad  10  mentioned above. Description to them is omitted here.  
         [0024]     Moreover, it is to be understood that the invention may be embodied in other forms without departing from the spirit thereof. Thus, the present examples and embodiments are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.