Abstract:
A system and method for receiving character entries in mobile computer devices uses an improved keypad. The keypad uses a dual key press method in which each key of the keypad includes a unique key definition when it alone is pressed. Each of two adjacent keys of the keypad also include a unique key definition when the two adjacent keys are pressed at substantially the same time. A keypad controller receives inputs from the keys and decodes the single key entries and the dual key entries. The keypad occupies a relatively small keypad area while providing full size keys for the user. The keypad also has a mode key that enables a user to change the alphabet mode of the keypad to a numerical mode.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) AND CLAIM OF PRIORITY 
     The present application is related to U.S. Provisional Patent No. 61/203,976, filed Dec. 31, 2008, entitled “SYSTEM AND METHOD FOR PROVIDING AN IMPROVED KEYPAD”. Provisional Patent No. 61/203,976 is assigned to the assignee of the present application and is hereby incorporated by reference into the present application as if fully set forth herein. The present application hereby claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent No. 61/203,976. 
    
    
     TECHNICAL FIELD 
     This disclosure is generally directed to a keypad for computer devices. More particularly, this disclosure is directed to a keypad for small mobile computer devices. 
     BACKGROUND 
     For many mobile computer devices, the keypad is the primary user interface. As mobile computer devices become smaller, the area that is available on the devices for the keypad becomes critically limited. As the available keypad space on a device becomes more and more limited, the size of the keys on the keypad becomes smaller and smaller. The small key size makes it more difficult for a user to accurately press the keys. This is because the size of the end of the user&#39;s finger is large with respect to the small size of the keys. When the user is attempting to press one particular key, the user&#39;s finger may inadvertently press an adjacent key as well. This may result in an incorrect signal being sent from the keypad to the computer device. 
     SUMMARY 
     A system for entering characters into a computer device is provided. The system includes a keypad and a controller. The keypad includes a plurality of keys. The keypad is configured to send a first signal when a first key is depressed and a second signal when a second key is depressed. The controller is configured to receive the first and second signals. The controller further is configured to identify a first character when the first signal is received and a second character when the first and second signals are received at substantially the same time. 
     A method for entering characters into a computer device is provided. The method includes receiving a key stroke signal from a keypad. The keypad includes a plurality of keys. Each key is associated with at least one character. The key stroke signal is associated with a first character when a first key is depressed and a second character when the first key and a second key are depressed at substantially the same time. The method also includes determining a selected character associated with the key stroke signal. 
     A portable computer device is provided. The device includes a keypad and a controller. The keypad includes a plurality of keys. Each key is associated to at least one of a number of characters. The keypad is configured to send a key stroke signal corresponding to a selected character. The controller is configured to receive the key stroke signal and use the key stroke signal to identify a first character when a first key is depressed and a second character when the first key and a second key are depressed at substantially the same time. 
     It may be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The term “couple” and its derivatives refer to any direct or indirect communication between two or more elements, whether or not those elements are in physical contact with one another. The terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation. The term “or” is inclusive, meaning and/or. The phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like. The term “controller” means any device, system, or part thereof that controls at least one operation. A controller may be implemented in hardware, firmware, software, or some combination of at least two of the same. The functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of this disclosure, reference is now made to the following description, taken in conjunction with the accompanying drawing, in which: 
         FIG. 1  illustrates an exemplary structure of a keypad having a numeric centric layout according to one advantageous embodiment of the invention; 
         FIG. 2  illustrates an exemplary structure of a keypad having a QWERTY layout according to another advantageous embodiment of the invention; and 
         FIG. 3  is schematic diagram of a system of the invention that comprises a keypad controller for controlling a keypad of the invention according to an advantageous embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1 through 3 , discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged computer device. 
       FIG. 1  illustrates an exemplary structure of a keypad  100  having a numeric centric layout according to some embodiments of the present disclosure. The embodiment of the keypad  100  shown in  FIG. 1  is for illustration only and other embodiments could be used without departing from the scope of this disclosure. 
     As shown in  FIG. 1 , the keypad  100  includes twelve full size keys arranged in a three by four matrix. The term “full size” means that the size of the key is large enough to easily receive and accommodate a fingertip of a user. It is understood that while some embodiments may operate with full size keys, other embodiments may be used with keys of any size. 
     The twelve keys are designated with reference numerals  110  through  121 . Key  110  represents the letter ‘A’. When a user presses key  110 , a single key stroke signal is sent to a controller (not shown in  FIG. 1 ) that represents the unique key definition for the letter ‘A’. This feature is represented by the letter ‘A’ placed in the center of key  110 . 
     Key  111  represents the letter ‘C’. When the user presses key  111 , a single key stroke signal is sent to the controller (not shown in  FIG. 1 ) that represents the unique key definition of the letter ‘C’. This feature is represented by the letter ‘C’ placed in the center of key  111 . 
     Key  110  and key  111  taken together (i.e., pressed at substantially the same time) represent the letter ‘B’. When the user presses key  110  and key  111  at essentially the same time, a dual key stroke signal is sent to the controller (not shown in  FIG. 1 ) that represents the unique key definition of the letter B. The dual key stroke signal can be pair of signals including a first signal associated with the first key  110  and a second signal associated with the second key  111 ; the dual key stroke signal can be a single signal that is a combination of the first signal associated with the first key  110  and the second signal associated with the second key  111 , or the dual key stroke signal can be a single signal that represents the first signal associated with the first key  110  and the second signal associated with the second key  111 . This feature is represented by the letter ‘B’ placed between key  110  and key  111 . 
     When the user presses two keys at essentially the same time (i.e., pressed at substantially the same time), a first signal from one of the two keys may be sent from the keypad  100  before a second signal from the other key is sent from the keypad  100 . Although the user presses the two keys at essentially the same time, a small interval of time may exist between the two signals from the keypad  100 . A keypad controller  330  (shown in  FIG. 3 ) will consider the two signals to be simultaneously sent by the keypad  100  if the keypad controller  330  receives the two signals within a pre-specified period of time. 
     The arrangement and structure of keypad  100  allows the user to select the letter ‘A’, the letter ‘B’, or the letter ‘C’ using two full size keys (key  110  and key  111 ). This means that the keyboard  100  can provide full size keys for a full alphabet of letters in a relatively small area. 
     The keypad  100  also provides adjacent keys in a vertical direction. For example, key  114  represents the letter ‘K’. When a user presses key  114 , a single key stroke signal is sent to a controller (not shown in  FIG. 1 ) that represents the unique key definition for the letter ‘K’. This feature is represented by the letter ‘K’ placed in the center of key  114 . 
     Key  117  represents the letter ‘S’. When the user presses key  117 , a single key stroke signal is sent to the controller (not shown in  FIG. 1 ) that represents the unique key definition of the letter ‘S’. This feature is represented by the letter ‘S’ placed in the center of key  117 . 
     Key  114  and key  117  taken together (i.e., pressed at the substantially the same time) represent the letter ‘O’. When the user substantially simultaneously presses key  114  and key  117 , a dual key stroke signal is sent to the controller (not shown in  FIG. 1 ) that represents the unique key definition of the letter ‘O’. The dual key stroke signal can be a pair of single key stroke signals including a first signal associated with the first key  114  and a second signal associated with the second key  117 ; the dual key stroke signal can be a single signal that is a combination of the first signal associated with the first key  114  and the second signal associated with the second key  117 ; or the dual key stroke signal can be a single signal that represents the first signal associated with the first key  114  and the second signal associated with the second key  117 . This feature is represented by the letter ‘O’ placed between key  114  and key  117 . 
     The keypad  100  provides the entire alphabet from ‘A’ to ‘Z’ using twelve full size keys arranged in a three by four array as shown in  FIG. 1 . The letter ‘V’ is selected by substantially simultaneously pressing key  116  for the letter ‘Q’ and the Mode key  119 . The letter ‘X’ is selected by substantially simultaneously pressing key  118  for the letter ‘U’ and the blank key  121 . The letter ‘Y’ is selected by substantially simultaneously pressing the Mode key  119  and the blank key  120 . The letter ‘Z’ is selected by substantially simultaneously pressing the blank key  120  and the blank key  121 . 
     Numbers ‘0’ through ‘9’ may be associated with a number of respective keys of the keypad  100 . In one embodiment, the number ‘1’ is associated with the ‘A’ key  110 , the number ‘2’ is associated with the ‘C’ key  111 , the number ‘3’ is associated with the ‘E’ key  112 , and so forth. The number ‘0’ is associated with the blank key  120 . When the user, at substantially the same time, presses the Mode key  119  and one of the keys associated with a number the keypad  100 , the number is selected and an appropriate signal, or signals, is sent to the controller that represents the selected number. 
     For example, assume that the user substantially simultaneously presses the ‘Mode’ key  119  and the ‘K’ key  114 . Pressing this combination of keys ( 119  and  114 ) selects the number five (5) that is associated with the ‘K’ key  114 . The keypad  100  therefore provides the entire alphabet from ‘A’ to ‘Z’ and numbers ‘0’ through ‘9’ using twelve full size keys arranged in a three by four array as shown in  FIG. 1 . 
       FIG. 2  illustrates an exemplary structure of a keypad  200  having a QWERTY layout according to some embodiments of the present disclosure. The embodiment of the keypad  200  shown in  FIG. 2  is for illustration only and other embodiments could be used without departing from the scope of this disclosure. 
     The keypad  200  operates in a manner that is similar to the manner that has been previously described for keypad  100 . However, as shown in  FIG. 2 , keypad  200  includes eighteen full size keys arranged in an array of three keys by six keys. The first key is the key  210  for the letter ‘Q’. The second key is the key  211  for the letter ‘E’. In the manner that has been previously described, pressing the ‘Q’ key  210  and the ‘E’ key  211  at substantially the same time selects the letter ‘W’. The sequence of letters in keypad  200  is arranged in the QWERTY sequence of a typewriter. 
     Numbers ‘0’ through ‘9’ may be associated with a number of respective keys of the keypad  200 . In one embodiment, the number ‘1’ is associated with the ‘Q’ key  210 , the number ‘2’ is associated with the ‘E’ key  211 , the number ‘3’ is associated with the ‘T’ key  212 , and so forth. When the user presses, at substantially the same time, the ‘Mode’ key  222  and one of the keys associated with a number the keypad  200 , the number is selected and an appropriate signal, or signals, is sent to the controller that represents the selected number. 
       FIG. 3  is schematic diagram of a system  300  including a controller  330  for controlling the keypad  310  according to some embodiments of the present disclosure. The embodiment of the keypad  300  shown in  FIG. 3  is for illustration only and other embodiments could be used without departing from the scope of this disclosure. 
     The keypad  310  provides key stroke signals  320  to the keypad controller  330 . The keypad controller  330  includes a computer memory unit  340 . The computer memory unit  340  includes a dual key press decode unit  350  and an operating system  360 . The keypad controller  330  includes computer hardware and computer software instructions that cooperate and work together to carry out the operations of the keypad controller  330 . 
     The keypad controller  330  can receive both single key stroke signals and dual key stroke signals from the keypad  310 . The keypad controller  330  uses the dual key press decode unit  350  to decode the various key stroke signals. In this manner the keypad controller  330  determines which letter of the alphabet (and which numeral when the Mode key is pressed) is associated to the received key stroke signal. 
     A mobile computing device may include a system  300  that includes the keypad  310  and the keypad controller  330 . The a mobile computing device can be a portable device such as, but not limited to, a cellular telephone, a handheld computer, a personal digital assistant (PDA), a global positioning system (GPS), and any other similar type of device. 
     While this disclosure has described certain embodiments and generally associated methods, alterations and permutations of these embodiments and methods will be apparent to those skilled in the art. Accordingly, the above description of example embodiments does not define or constrain this disclosure. Other changes, substitutions, and alterations are also possible without departing from the spirit and scope of this disclosure, as defined by the following claims.