Abstract:
A computer input method is disclosed which comprises obtaining a time interval elapsed from a time when a key of a keyboard is pressed to a time when the pressed key is released, comparing the time interval with a predetermined time period, and producing a code corresponding to the pressed key in case the time interval is equal to or shorter than the first predetermined time period.

Description:
BACKGROUND 
       [0001]    The present invention relates generally to human input devices for computing systems, and, more particularly, to a computer keyboard and mouse combo device. 
         [0002]    A most popular way to position a cursor on a computer display is to use a mouse, which functions by detecting two dimensional motions relative to its supporting surface. Physically, a mouse comprises an object held under one of a user&#39;s hands, with one or more buttons. Clicking or hovering (stopping movement while the cursor is within the bounds of an area) can select files, programs or actions from a list of names, or (in graphical interfaces) through small images called “icons” and other elements. For example, a text file might be represented by a picture of a paper notebook, and clicking while the cursor hovers over this icon might cause a text editing program to open the file in a window. 
         [0003]    When mice have more than one button, software may assign different functions to each button. Often, a primary (leftmost in a right-handed configuration) button on the mouse will select items (primary click), and a secondary (rightmost in a right-handed) button will bring up a menu of alternative actions applicable to that item (secondary click). 
         [0004]    A conventional keyboard can detect a pressing of any key thereof, but cannot detect mere touches on the keys. Here, the “touch” refers to a surface of the keyboard being contacted by an object regardless if the key is pressed or not. If the conventional keyboard is a tactile one, the key pressing results from the key being depressed. If the conventional keyboard is a surface one, such as Touch Cover for Microsoft Surface, the key pressing results from a force being applied on the key. As long as the key remains depressed in tactile keyboard or forced upon in surface keyboard, the key is pressed. 
         [0005]    While conventional mice can be highly accurate pointing devices for computers, being a separate device the conventional mice have some short-comings, such as every time when a computer user wants to move a cursor, he or she has to move his or her hand away from the keyboard and to the mouse, and move the mouse as a physical object. It is not only less efficient but also may cause injury to the hand over an extended period of time of use. 
         [0006]    As such, what is desired is a computer input device, particularly a pointing device that does not rely on moving any additional object other than the user&#39;s fingers. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0007]      FIG. 1  is a perspective view of a laptop computer with a keyboard. 
           [0008]      FIG. 2  illustrates an infrared-light touch sensing system positioned to detect touch on the keyboard surface according to an embodiment of the present invention. 
           [0009]      FIG. 3  is a layout diagram of keyboard keys according to the embodiment of the present invention. 
           [0010]      FIG. 4  is a block diagram of a computing system with a keyboard-mouse combo device according to the embodiment of present invention. 
           [0011]      FIG. 5  is a flow chart diagram illustrating steps of operations of the keyboard-mouse combo device according to an embodiment of the present invention. 
       
    
    
       [0012]    The drawings accompanying and forming part of this specification are included to depict certain aspects of the invention. A clearer conception of the invention, and of the components and operation of systems provided with the invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiments illustrated in the drawings, wherein like reference numbers (if they occur in more than one view) designate the same elements. The invention may be better understood by reference to one or more of these drawings in combination with the description presented herein. 
       DESCRIPTION 
       [0013]    The present invention relates to a computer input device utilizing a touch sensing device and a conventional keyboard to provide cursor input for the computer. A preferred embodiment of the present invention will be described hereinafter with reference to the attached drawings. 
         [0014]      FIG. 1  is a perspective view of a laptop computer  100  with a conventional keyboard  105  for entering text, etc. The laptop computer  100  has a base unit  102  containing the keyboard  105 , and a display panel  115  which is hinged to the base unit  102  by hinges  118 . A skilled computer user can generally type on the keyboard  105  with both hands  123  and  124 . 
         [0015]      FIG. 2  illustrates an infrared-light touch sensing system positioned to detect touches on the surface of the keyboard  105  according to an embodiment of the present invention. The infrared-light touch sensing system includes an infrared light emitter  202  and an infrared light receiver  208 . The infrared light travels across the surface of the keyboard  105 . A finger  124  or any other object touching the surface of the keyboard  105  blocks the infrared light from being received by the infrared light receiver  208 . As a result, the touch can be detected. 
         [0016]    Referring back to  FIG. 1 , the infrared light emitter  202  can be positioned along one edge of the keyboard  105  and the infrared light receiver  208  can be positioned along the opposite edge of the keyboard  105 . In order to obtain coordinates of a touch, two sets of the infrared light touch sensors will be needed with one set positioned on the horizontal edges and the other on the vertical edges. 
         [0017]    Although an infrared-light touch sensing system is described hereinbefore, other touch sensing systems, such as the one using a video camera or ultrasound can also be used. 
         [0018]      FIG. 3  is a layout diagram of keys of the keyboard  105  according to the embodiment of the present invention. A predetermined touch sensing area  310  is designated by a keyboard-mouse combo (KMC) software for detecting a touch and extracting coordinates of the touch. Only touches within the touch sensing area  310  can be detected as effective touches by the touch sensing system. The predetermined touch sensing area  310  can also be marked out on the surface of the keyboard  105 , so that a computer user can clearly identify a boundary of the touching sensing area. The predetermined touch sensing area  310  functions akin to Apple&#39;s Magic Trackpad surface area. Apparently, the touch sensing area  310  has to be entirely covered by infrared light. Even though a touch on areas outside of the predetermined touch sensing area  310  can be picked up by the infrared-light sensing system, the KMC software ignores such touch. 
         [0019]    Referring again to  FIG. 3 , there is a designated key  322  marked as “AUX” which stands for “auxiliary”, outside of the predetermined touch sensing area  310 . A main function of the “AUX” key  322  is for switching between a primary click and a secondary click. Operation details of the “AUX” key  322  are depicted in  FIG. 5  and associated paragraphs hereinafter. Although only one “AUX” key  322  on the left hand side of the keyboard  105  is illustrated in  FIG. 3 , a skilled in the art would realize that another “AUX” key can be designated on the right hand side of the keyboard  105  as well. 
         [0020]      FIG. 4  is a block diagram of a computing system  400  with a KMC device according to the embodiment of present invention. The computing system  400  includes an input device  410 , a display  420 , an input/output (I/O) processor  430 , a central processing unit (CPU)  440  and a memory and storage unit  450 . The input device  410  comprises a conventional keyboard  412  and a touch sensor  415  which overlays the conventional keyboard  410  as described in  FIGS. 1-3 . The conventional keyboard  412  and the touch sensor  415  form the KMC device. The I/O processor  430  is the hardware that executes the KMC software. The I/O processor  430  also includes a timer  432  for measuring a length of time when a key is pressed. 
         [0021]      FIG. 5  is a flow chart diagram illustrating steps of an operation of the KMC device according to an embodiment of the present invention. The keyboard-mouse operation starts with detecting, in step  510 , if the touch sensing area  310  is touched and if any key of the keyboard  105  is pressed. The I/O processor  430  distinguishes a single touch from no-touch or multiple touches in step  520 . Here the multiple touches refer to a situation when the touch sensing area  310  is simultaneously touched at multiple noncontiguous locations. If there is no single touch, i.e., the touch sensing area  310  is either not touched or simultaneously touched at multiple locations, the keyboard-mouse operation enters into a keyboard mode in step  560 , in which when a key is pressed, the I/O processor  430  outputs a code corresponding to the pressed key, and cursor on the display  420  does not move in spite of a touch relocation. 
         [0022]    If a single touch is detected in step  520 , the keyboard-mouse operation further detects if there is any key being pressed in step  530 . In case there is no key being pressed, the keyboard-mouse operation enters into a mouse mode in step  535 , in which relocations of the single touch will be interpreted as cursor movement on the display  420 . In case a key press is detected in step  530 , the keyboard-mouse operation further detects if the pressed key is released within a first predetermined time period (T 1 ) in step  540 . In order to execute step  540 , the timer  432  is started upon a key is pressed, and stopped when the key is released. Then a time recorded by of the timer  432  is compared with T 1 . In some embodiments, T 1  is set at 300 milliseconds and the value is stored in the I/O processor  430 . 
         [0023]    In case the pressed key is released within T 1  time period in step  540 , the keyboard-mouse operation enters into the keyboard mode in step  560  and treats the key press as a keyboard entry. In case the pressed key is released after the T 1  time period, the keyboard-mouse operation further detects, in step  550 , if the pressed key is released within a second predetermined time period (T 2 ) which is longer than T 1 . In some embodiments, T 2  is set at 2 seconds and the value is stored in the I/O processor  430 . 
         [0024]    Following step  550 , in case the pressed key is released within T 2  time period, the keyboard-mouse operation enters into the mouse mode and performs a left click operation in step  553 . In case the pressed key is released after the T 2  time period, the keyboard-mouse operation enters into the mouse mode and performs a right click operation in step  557 . 
         [0025]    Referring back to  FIG. 5 , after every mouse mode or keyboard mode operation (step  535 ,  553 ,  557  or  560 ), the keyboard-mouse operation returns to step  510  and run through the steps depicted in  FIG. 5  again. In effect, the touch sensing area  310  keeps detecting touches and the keyboard  105  keeps detecting key presses during an entire time the KMC device is turned on. 
         [0026]    Although much of the keyboard-mouse operation steps as described above is executed by the I/O processor  430 , in other embodiments, all or some of the same steps may be executed by the CPU  440  instead. 
         [0027]    The above illustration provides many different embodiments or embodiments for implementing different features of the invention. Specific embodiments of components and processes are described to help clarify the invention. These are, of course, merely embodiments and are not intended to limit the invention from that described in the claims. 
         [0028]    Although the invention is illustrated and described herein as embodied in one or more specific examples, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention, as set forth in the following claims.