Abstract:
A low profile pointing device for personal computers includes a thin elongate case for insertion in a PC Card slot and defining a cavity therein. A frame forms one surface of the case and defines an opening therethrough. A slidable plate is disposed within the cavity and is translatably supported in a plane parallel to the frame. A portion of the slidable plate is accessible through said frame opening. At least one motion sensor is mounted within the case and is coupled with the slidable plate for sensing movement of the plate and converting the sensed movements into electrical data signals. A communication interface transmits data signals between the motion sensor and the computer.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/919,205, filed Mar. 21, 2007. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to pointing devices for personal computers in general and more particularly to a low profile external pointing device. 
   2. Discussion of the Related Art 
   Personal computers have become an integral part to the business and personal activities of a large number of today&#39;s individuals. The personal computer has evolved from a desktop box with a CRT monitor largely limited in one fixed location to a state-of-the-art compact notebook with a flat panel display exhibiting processing power and display resolutions only dreamed of a few years ago. Today&#39;s notebook computers are small and continue to shrink even as their power continues to expand. These computers utilize operating systems that typically incorporate a graphical user interface (GUI). One of the primary aids for using a GUI is the incorporation of a pointing device to facilitate inputs into the computer. A pointing device permits the users to freely move a “pointer” or cursor around the display screen, to make selections and numerous other functions. 
   The most common pointing device is a mouse, which typically incorporates a captive ball that is rotated by translating the mouse across a flat surface. An electro-mechanical mechanism in the mouse translates the ball movement into electrical signals that are translated by the computer into movements of the onscreen pointer. The mouse will also incorporate one or more switches or buttons operated by the user&#39;s fingers to perform additional functions with respect to the onscreen display. Various configurations of pointing devices have been developed over the years in addition to the mouse such as trackballs, touchpads, joysticks, and touch screens to name a few. Each functions to move the onscreen pointer and has associated therewith one or more input function buttons. However, by far, the most common pointing device associated with a computer is a mouse. 
   The typical mouse is somewhat voluminous compared to the size of small notebook computers. Manufacturers of notebooks, seeking to retain the mouse&#39;s capacities while maintaining the small size of the computer, devised the touchpad, which is a thermal-sensor based device to move the computer&#39;s cursor. 
   While the touchpad does perform the same functions as a mouse, it does so in a way quite different to the manner in which mouse users are accustomed. Use of the touchpad requires repetitive finger movement, leading to a somewhat cumbersome manner of use. In addition, should the user&#39;s finger be slightly moist, the performance of the thermal sensors in the pad is degraded. The touchpad is normally located in the center front portion of the keyboard. While this placement accommodates both right- and left-handed users, this compromise position is not particularly comfortable for either to use, since most mouse users, be they right- or left-handed, are accustomed to having the mouse located on a particular side of the keyboard. 
   The result is that users of notebook computers, who find such pads inefficient, resort to the use of an external mouse even though its volume is cumbersome with relation to the size of the computer. The use of an external mouse somewhat defeats the purpose of the drive towards smaller size and requires the user to carry a separate piece of equipment in additions to the notebook computer. One attempt to alleviate this problem was the development of the mini-mouse. The mini-mouse is smaller than a normal mouse, but is still voluminous compared to the size of the laptop or notebook computer. Further, this external mouse must still be packed separately when traveling. Recently, a flat wireless mouse, the MoGo™, which is storable in the PC Card slot of a notebook computer has been introduced. This is also a touchpad device, but not fully functional. 
   The use of an external mouse requires the presence of a flat surface near the computer on which to operate the mouse. However, often notebook computers are used on the user&#39;s lap or other location where no such useable flat surface may be available. The user must then be content using the cumbersome touchpad. Current mouse designs take on many forms. Some designs attempt to be more ergonomic, since it has been shown that repetitive use of a mouse, which requires grasping it, may lead to physical discomfort, carpal tunnel syndrome, or other repetitive motion injuries. 
   Thus what is desired is a computer pointing device that is relatively small with respect to a notebook computer. 
   SUMMARY OF THE INVENTION 
   The present invention is a pointing device that utilizes a sliding plate to direct the onscreen motion of the screen pointer while performing all the mouse&#39;s functions. Like a touchpad on current notebook computers, the new pointing device uses the motion of the user&#39;s finger but with a sliding plate as the input device, thereby allowing the user&#39;s finger to perform all the mouse&#39;s functions with easier and more familiar movements. In addition, variants of two embodiments allow its use as a PC desktop mouse that is also highly ergonomic. Use of the pointing device should reduce the repetitive motion difficulties that many users experience in repeatedly grasping a mouse, since this pointing device requires no grasping and in use the hand is practically flat which is a more normal position for the hand. 
   In one aspect of the present invention the pointing device for personal computers includes a thin elongate case for insertion in a PC Card slot and defining a cavity therein. A frame forms one surface of the case and defines an opening therethrough. A slidable plate is disposed within the cavity and is translatably supported in a plane parallel to the frame. A portion of the slidable plate is accessible through said frame opening. At least one motion sensor is mounted within the case and is coupled with the slidable plate for sensing movement of the plate and converting the sensed movements into electrical data signals. A communication interface transmits data signals between the motion sensor and the computer. 
   Another aspect of the present invention is an ergonomic pointing device for use with personal computers and includes a multi-segmented case wherein a first midsection defines a cavity therein and a second midsection is substantially coplanar and slidable with respect to the first midsection. Each of the first and second midsections have distal ends that are hingedly affixed thereto such that the distal ends are selectively rotatable between a first stored position and a second extended position forming support legs for the multi-segmented case. A removable frame forms one surface of the first midsection and defines an opening therethrough. A slidable plate is disposed within the cavity and has a portion thereof exposed through the frame opening. The slidable plate is translatably supported in a plane substantially parallel to the frame. At least one motion sensor is mounted within said case and is coupled with the slidable plate for sensing movement of the slidable plate. A communication interface transmits data signals between said motion sensor and the computer. 
   These and other features, aspects, and advantages of the invention will be further understood and appreciated by those skilled in the art by reference to the following written specification, claims and appended drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a fuller understanding of the nature of the present invention, reference should be made to the accompanying drawings in which: 
       FIG. 1  is a perspective view of a notebook embodying the present invention, wherein a pointing device in insertable in either a left or right PC Card slot; 
       FIG. 2  is a plan view of the pointing device; 
       FIG. 3  is a cross-sectional front elevation view of the pointing device shown in  FIG. 2  and taken along the line  3 - 3 ,  FIG. 2 ; 
       FIG. 4  is an end elevation view of the pointing device illustrating the interface electrical connector configuration; 
       FIG. 5  is a cross-sectional end elevation view of the pointing device shown in  FIG. 3  and taken along the line  5 - 5 ,  FIG. 3 . 
       FIG. 6  is a front elevation view of a computer having a pointing device connected thereto with an electrical cable; 
       FIG. 7  is a plan view of an alternate embodiment pointing device for integral embedment in the chassis of a notebook computer; 
       FIG. 8  is a front perspective exploded view of a computer with a pointing device for direct attachment to electrical interface connectors; 
       FIG. 9  is a plan view of the pointing device of  FIG. 8 ; 
       FIG. 10  is a front elevation view of a computer having an alternate embodiment pointing device connected thereto with an electrical cable; 
       FIG. 11  is a top plan view of an alternate embodiment pointing device for use as standalone pointing device; 
       FIG. 12  is a top plan view of an ergonomically designed free standing pointing device; 
       FIG. 13  is a side elevation view of the pointing device of  FIG. 12 . 
   

   Like reference numerals refer to like parts throughout the several views of the drawings. 
   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   For purposes of description herein, the terms “upper”, “lower”, “left”, “rear”, “right”, “front”, “vertical”, “horizontal”, and derivatives thereof shall relate to the invention as oriented in  FIGS. 1 and 2 . However, one will understand that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. Therefore, the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. 
   Turning to the drawings,  FIG. 1  shows a computer-pointing device  50 , which is one of the preferred embodiments of the present invention and illustrates its various components. A notebook computer  20  comprises a typical design having a chassis  22  that includes a flat panel display screen  24 , a keyboard  26 , and various electronics (not shown) for processing data. Computer  20  also includes PC Card slots  30 ,  32  wherein slot  30  is positioned on a left side of chassis  22  and slot  32  is positioned on a right side of chassis  22 . A low profile pointing device  50  according to the present invention, conforming to the form factor of an industry standard PC Card, can be received in either PC Card slot  30  or  32  for use in either a left-handed configuration (when received in slot  30 ) or a right-handed configuration (when received in slot  32 ). 
   Referring now to  FIGS. 1-5 , a preferred embodiment of the pointing device  50  includes a thin elongate case  136  substantially conforming to the form factor of a notebook computer PC Card and having substantially identical removable frames  105 , each frame  105  defining a rectangular opening  124  therethrough. Within a cavity defined by case  118 , a set of upper motion sensing rollers  120  are in vertical registration with a set of lower motion sensing rollers  122 , and distributed around a periphery of openings  105 . In the most preferred embodiment, one each of sensor rollers  120 ,  122  are associated with one side of the rectangle defined by opening  105 . An electromechanical motor  123  can be incorporated within at least one of the sensor rollers  120 ,  122 . 
   A sliding plate  100  is movably supported between rollers  120 ,  122  within the cavity such that sliding plate  100  is horizontally movable in any direction. Sliding plate  100  includes surfaces  107  for placement of a user&#39;s finger to initiate translation of plate  100 . Surfaces  107  can be textured to increase the frictional force between the user&#39;s finger and plate  100  and between plate  100  and rollers  120 ,  122 . Surfaces  107  can also have a non-stick, non-adherent coating. Rollers  120 ,  122  are similar in function to a current art computer mouse that incorporates a rolling ball and positioned in the same manner at 90 degrees relative to each other, thus providing for movement of the cursor on the screen, in all axes. Rollers  120 ,  122  are spring mounted by spring arms  102  biasing sensor rollers  120 ,  122  one in opposition to the other to assure constant contact with plate  100 . Each sensor roller  120 ,  122  is mounted with a hinge  103  to permit sensor rollers to be folded away from plate  100  thereby allowing sliding plate  100  to be removed for cleaning. Further, each sensor roller  120 ,  122  in contact with the plate  100  is mounted on a small internal electro-mechanical motor controlled by computer  20 . Other methods of moving rollers  120 ,  122  are contemplated, but the motor-controlled rollers are most preferred. In such a configuration plate  100  may also be remotely slid in its lateral plane by rollers  120 ,  122  driven by the internal electro-mechanical motors. 
   In lieu of roller sensors  120 ,  122 , an optical sensing system may be incorporated wherein a movement of an optical pattern on surface  107  is optically sensed and transmitted to the operating software whereupon that movement is translated into a corresponding movement of the cursor on display  24 . Other sensing systems are also contemplated for incorporation into device  50 . 
   The dimensions of plate  100  are limited by the surface area of the card embodiments. Since pointing device  50  must fit into PC slot  30 ,  32  in notebook computer  20 , the card&#39;s maximum dimensions are therefore currently 0.21 inch/5 mm thick, and 2.125 inches/54 mm wide. However, device  50  is preferably slightly longer than the length (2.875 inches/74 mm) of slots  30 ,  32 , making device  50  protrude slightly from the case  22  of notebook  20 . This protrusion permits pointing device  50  to have a slightly greater dimension in length than width, similar to the dimensional proportions of the computer display. The slightly longer length of pointing device  50  permits for the placement of a groove  104  in the top and bottom surfaces at the protruding end  128  of device  50 . Groove  104  allows the device  50  to be gripped easily and pulled out manually from slots  30 ,  32 . It is understood the dimensions provided are based upon the current standard format and that the PC slot can be of any reasonable dimensions for slots having equivalent functions.” 
   As illustrated in  FIG. 2 , pointing device  50  further includes a plurality of function control switches  109 - 111  arrayed along one edge of device  50 . Function control switches  109 - 111  perform functions substantially identical to those found on prior art pointing devices. Switches  109 ,  110  function as right and left “click” buttons for interaction with the GUI implemented on computer  20 . Switches  109 ,  110  are each mounted on a hinge  116 . This is necessary so that switches  109 ,  110  may serve on both top and bottom of device  50  when it is used in a right- or left-handed position. Switch  111  functions as a “scroll” switch and is preferably located between “click” switches  109  and  110 . Switch  111  is spring-actuated and slides in a groove  131  so that it returns to its neutral position after use. Switches  109 - 111  are positioned such that they are equally accessible from either the top or bottom surfaces of device  50 . Other control buttons may also be located on the surface. 
   Referring to  FIGS. 2-4 , inserted end  113  of device  50  includes at each side thereof a female mini-USB jack  114  (or other suitable interface) that forms part of a communication interface between device  50  and computer  20 . Jacks  114  are oriented  180  degrees one from the other such that a  180  degree reorientation of device  50  will present an identical jack  114  configuration and its interface pins  115  are in the correct up/down position for engagement of a male mini-USB jack in slots  30 , 32 . 
   Removable frames  105  define holes  112  near each of the four corners thereof, into which are received footpads  126 . In general, for a majority of the embodiments, four foot pads  126  are placed into holes  112  in order to transform the PC Card slot pointing device  50  into a variant usable as desktop pointing device. 
   In use, device  50  is inserted into either PC slot  30 ,  32 , and is particularly useful with notebook  20  when a flat space normally required for an external mouse is not available. When inserted in slot  32 , device  50  functions as a right-handed pointing device. In this orientation switch  110  functions as the “left-click button” found on prior art devices and switch  109  functions as the “right-click button” found on prior art devices. However, device  50  can be inverted for insertion into PC slot  30  on the left side of notebook computer  20  whereupon it functions as a left-handed device. In this orientation switch  109  functions as the “left-click button” found on prior art devices and switch  110  functions as the “right-click button” found on prior art devices. In both orientations, switch  111  retains its “scroll” function. The operating software installed in notebook computer  20  driving device  50  recognizes the slot  30 ,  32  in which device  50  is engaged and automatically configures switches  109 ,  110  to the correct “handedness.” Further, the operating software automatically configures the electrical inputs from rollers  120 ,  122  to correlate a directional movement of plate  100  with a corresponding directional movement of the pointer on display  24 . 
   Pointing device  50  is usable with notebook computers having an integral touch pad for those users who desire an alternative pointing device but do not wish to use an external mouse. Future notebook computers can incorporate pointing device  50  as a primary pointing device in lieu of a touch pad. When fully inserted in slot  32 , device  50  is locked in place by a spring-actuated lock  134 . When fully seated in slot  32 , device  50  can be slightly ejected either by pushing inwards upon the exposed end  128  or by pushing a release button  106 . In either case, the spring-actuated lock  134  in the rear of slot  32  is released, thereby pushing device  50  slightly out of slot  32 . Grasping device  50  by groove  104 , device  50  can then be manually pulled outwards to its functioning position, at which point it locks into that position. In the event of a failure of the spring-loaded lock or ejection mechanism  134  or ejection button  106 , grasping device  50  by groove  104  permits device  50  to be manually pulled out of PC slot  32 . As the device  50  is pulled into its functioning position, the internal interfaced USB-jack  114  slides along a spring-loaded track  52 , allowing the interface to remain engaged when device  50  is in its operating position, and further facilitates retraction of the interface when device  50  is pushed back into slot  32  for storage. 
   Once device  50  is in its operating position, the user places a finger on surface  107  of plate  100  and translates plate  100  within its operational plane. The planar translations of plate  100  cause sensor rollers  120 ,  122  to rotate about their respective axes. The rotations of sensor rollers  120 ,  122  send proportional electrical signals to computer  22  which in turn are interpreted and translated into corresponding cursor movements on display  24 . For ease of use of plate  100 , it is preferable that the proportionality be such that a movement of plate  100  from its neutral position to any edge will accomplish the movement of the screen cursor to the edge of computer display  24  in that direction. It is also possible to program the operating software to movements of plate  100  where its movement is not very proportional to the movement of the display cursor. In this case plate  100 , when translated to a maximum lateral position such that the user&#39;s finger touches the removable frame  105 , the screen cursor would not move to the edge of the computer screen; rather, the screen cursor would continue movement in the direction of the plate&#39;s  100  previous direction, until the user removed the finger pressure on plate  100 . 
   The dimensions of plate  100  being necessarily smaller than case  118 , restrict the movement of plate  100  to an area less than the size of the device  50 . This limitation is similar to the functioning of the current-art touch pad of portable computers, and different from an external mouse, which can be moved over any flat surface for any theoretical distance. However, it is not necessary for plate  100  to move over significant distances in order to move the cursor over the entire screen. In current pointing devices movements of the device, and thus the cursor on the screen, are typically proportional; i.e., small movements of the mouse generate larger movements of the cursor. Since users of prior art pointing devices are accustomed to the proportionally greater movement of the cursor compared to input movements, no significant problem is anticipated for a user to become accustomed to the use of sliding plate  100 . 
   A user designates completion of a desired cursor function by relaxing finger pressure on plate  100  and subsequently depressing any key on the computer&#39;s keyboard or after a user-programmed predetermined time interval. Upon completion of such movements, plate  100  (and therefore the screen cursor) is either left in its last position or is automatically repositioned to its “neutral” position in the center of the frame by computer-controlled rotations of the rollers  120 ,  122  by commanding the electro-mechanical motors associated with each roller  120 ,  122 . If thus programmed, the automatic repositioning function allows for immediate resetting to the neutral position, and thus reuse of plate  100 , reducing the necessity for repetitive finger movement to position the cursor, as well as the most rapid average positioning of the cursor on display  24 . 
   Plate  100  may be depressed by the user&#39;s finger on its right or left side. Such a depression is sensed by the movement of springs  102  in hinge structure  103  of rollers  120 ,  122 . This depression is an alternate to the use of the right  109  or left  110  buttons, analogous to those on a computer mouse. Such deflection of springs  102  associated with each of sensor rollers  120 ,  122  is sensed when plate  100  is depressed greater than the finger pressure normally exerted to move the plate, and which pressure may be user defined. As in prior art pointer devices with right and left “click” buttons, when the display cursor is moved to a part of the display where a click function is enabled, depressing the left side of plate  100  once or twice can be programmed to be the equivalent of a corresponding one or two clicks on left button switch  110 . A corresponding once or twice depression of the right side of plate  100  can be programmed to be the equivalent of a corresponding one or two click on right button switch  109 . 
   Manipulation of plate  100  can also perform commonly used combination features such as “drag and drop,” and “cut, copy and paste” functions. These functions are analogous to those in prior art pointing devices; i.e., maintaining the left button  110  depressed to move an object, “cut”, “paste” “copy” in order to effect that function on text in a document. For example, to drag an object with sliding plate  100 , the cursor is moved by plate  100  to an object to be “dragged” whereupon the left side of plate  100  is depressed. While maintaining downward pressure on the sliding plate, the user then moves the cursor by again appropriately translating plate  100  to the onscreen position where the object is to be “dropped.” Thereupon the pressure on the left side of plate  100  is released, and the object is dropped. To drag text, the user depresses the left side of sliding plate  100  and, while maintaining that pressure, moving plate  100 , and thus the screen cursor, through the text to be “dragged.” Once the desired text has been selected, the pressure on plate  100  is released thereby highlighting the selected text. The user again depresses the left side of sliding plate  100  and, while maintaining such pressure, translates plate  100  until the cursor is placed where the text is to be “dropped”. Thereupon, the pressure on the plate is released, which “drops” the text at that point. The cutting, copying, and pasting functions are accomplished in a similar manner. These functions can be further customized through settings in the application software driving device  50 . In all the above operations, depressing the right  109  or left button  110  will have the same effect, since depressing and releasing plate  100  mimics the button operation of prior art pointing devices. Many users may find such functionality of sliding plate  100 , enabling these functions directly with the user&#39;s finger remaining on the plate, more convenient and advantageous than repeatedly moving a finger between buttons  109 - 110  and plate  100  to effect another operation. 
   When the screen cursor is positioned at a location on the screen where a computer-recognized scroll function is enabled, sliding button  111  in its guide slot or track  131  in either an up or down movement will perform the scroll function. Sliding button  111  towards either extremity will effect a “fast” scroll. Upon release of the button, the spring (not shown) will reposition button  111  to its “neutral” position in the center of the slide. Such a “fast scroll” functionality is a significant improvement over a prior art “scroll wheel.” Scroll wheels require repetitive movement of the wheel; however, with the fast scroll function, no repetitive movement is required. 
   Surface  107  of plate  100  is slightly lower than the top surface of device  50 , and is held in place by removable frame  105 , the surface of which is an outer surface of device  50 . Frame  105 , when removed, allows access for cleaning. To remove plate  100 , top rollers  120  are positioned upward on their respective hinges  103  so that plate  100  may be removed and cleaned. Removal of plate  100  gives access to the lower rollers  122  for cleaning. Periodic access for cleaning is necessary since dirt and dust may enter the unit through the small gap  108  between the surface  107  of plate  100  and plate frame  105 . 
   Plate  100  at the central area of each peripheral edge includes a protrusion  133  arcing upwards towards roller  120  and a protrusion  132  and arcing downwards towards roller  122 . Protrusions  132 ,  133  provide stops for the centering of plate  100  to the neutral position after cleaning. When hinge structures  103  signal that the four upper rollers  120  have been placed in an upward position allowing for removal of plate  100  for cleaning, computer  20  is placed in a “cleaning” mode. When plate  100  is replaced, computer  20  must recalculate and reposition plate  100  to its “neutral” position. This function is performed by commands from the application software that instruct the motorized rollers  120 ,  122  to slide plate  100  in a horizontal direction until rollers  120 ,  122  sense the contact of protrusions  132 ,  133  therewith and then repeating the movement in the vertical direction. Computer  20  thus can calculate the neutral position of plate  100  and command the motorized rollers  120 ,  122  to so position plate  100 . 
   Device  50  is powered by the mini-USB interface and may be completely pulled out of slot  32  pulling a cable interface (not shown) with it. Additionally, device may be fully disengaged from slot  32  other than its USB interface for use in a manner similar to a desktop mouse. During such an extraction, the cable is reeled out and remains connected to device  50 . In the event device  50  is disengaged from the cable for any reason, the male interface slides back to a position near the edge of the laptop, permitting the cable to be reengaged at will. 
   Another pointing device  60 , is shown in  FIG. 6  wherein device  60  is connected to computer  20  and utilized as a desktop pointing device. Device  60  incorporates the pointing device  50  in its PC Card configuration and further includes the addition of footpads  626  to the holes  112  of device  50  ( FIG. 2 ). Footpads  626  are removable, since device  60  cannot be reinserted into the PC slot  32  ( FIG. 1 ) with footpads  626  in place. Pointing device  60  is connected to computer  20  with a modified mini-USB cable  602 . One end of cable  602  is terminated with a male mini-USB jack  601  to connect to the female mini-USB port  614  of device  60  and the other end of cable  602  is terminated with a male USB jack  603  to connect to a standard USB port  604  on a side of the computer. Device  60  can also include a wireless capability to wirelessly communicate with computer  20 . Device  60  is illustrated herein as a right-handed pointing device, but can also be utilized as a left-handed device by connecting to a USB port on the left side of computer  20  and inverting pointing device  60  with foot pads  626  inserted into the holes  112  on the opposite side thereof. Computer  20  recognizes whether device  60  is connected to its right side or its left side and automatically configures device  60  accordingly in the same manner as discussed above with respect to the embodiment of pointing device  50 . 
   Referring now to  FIGS. 1 and 7 , an alternate embodiment pointing device  70  is illustrated and intended to be a replacement for prior art touch pads commonly found as standard in many notebook computers. Device  70  incorporates the same plate  100  and electro-mechanical rollers  120 ,  122  found in device  50  and functions in the same manner. Pointing device  70  is integrally incorporated into chassis  22  of notebook computer  20 . Since device  70  is intended for integral incorporation and notebook manufacturers may find it desirable to maintain a central location for a pointing device, it is positioned centrally between the left and right sides of chassis  22 , and therefore does not require the invertibility, as does device  50 . Right and left button switches  709 ,  710  are depressible in lieu of being on hinges as in device  50 , while scroll button  711  is identical to button  111  and slides in a track  731 . Device  70  includes a removable frame  605  for access to remove plate  700  for cleaning as described above. 
   Yet another embodiment is shown as pointing device  80  in  FIGS. 8-9 . Device  80  has a larger upper surface area and is thicker than preceding embodiments, since pointing device  80  is not intended to be received in a PC card slot. Device  80  uses a standard USB interface jack  92  on computer  20  and may be interfaced with computer  20  on either left or right side of computer  20 . The increased size of pointing device  80  enables a larger area sliding plate  800 , wherein the plate  100  has a larger movement area. Thus, the ratio of plate/cursor movement is preferably that of a standard prior art pointing device in current use. The larger size may provide more ease of use for some users. 
   Pointing device  80  has the same general surface appearance, controls, internal construction and software functions as pointing device  50  previously described with respect to  FIGS. 1-2 . 
   Pointing device  80  includes a male Type A USB plug  891  at an interface end  813  for electrical interface with computer  20 . USB plug  891  fits into Type A USB receptacle  92  on either side of the computer  20 . The USB interface connects pointing device  80  to the computer  20  for electrical communication and also supplies power to device  80 . Optionally, the interface may also be wireless. Since device  80  is not sized to fit into any computer slot, device  80  is carried separately from the computer  20 . Since standard USB Type A plugs and receptacles are orientationally keyed, the male USB plug  891  of device  80  can be rotated 180 degrees, in order for the device  80  to be used in either a right-handed or left-handed configuration.  FIG. 8  illustrates device  80  keyed for use as a left-handed pointing device. However by rotating USB plug  891  180 degrees, device  80  can be interfaced to the right side of computer  80 . 
   When interfaced with computer  20 , device  80  must be stabilized on the side of computer  20  in a more stable fashion than the single USB connection provides. In order to perform this stabilization function, a dummy stabilization plug  892  is utilized. Dummy stabilization plug  892  has no electrical connectivity between computer  20  and device  80  and fits into a standard USB Type A port  92  on a side of computer  20 . Since the spacing of USB ports  92  differ between models of notebook computers, the relative positions of the dummy stabilizer plug  892  and USB plug  891  should preferably be variable in separation. Device  80  facilitates this variability by mounting dummy stabilizer plug  892  in a rail  893  ( FIG. 8 ) on the insertion end  813  of device  80 . 
   In use, dummy stabilizer plug is positioned along rail  893  to correspond to the placement of USB jacks on the desired side of computer  20 . Device is then interfaced with computer  20  by inserting both active USB plug  891  and dummy stabilizer plug  892  in the respective USB ports  92  whereby dummy stabilizer plug  892  provides physical support for the body of device  80 . 
     FIGS. 10-11  illustrate a pointing device  90  configured for use as a desktop pointing device to replace prior art desktop pointing devices that are in popular use today. Device  90  may be used in either a right-hand or left-hand configuration and includes four foot pads  926  inserted into holes corresponding to holes  112  in pointing device  50  ( FIG. 2 ) so that device  90  remains securely positioned on the flat surface as the user desires. 
   Pointing device  90  includes a larger-sized plate  905  for ease of use and has the same surface appearance, controls, internal construction, and software functions as previous embodiments. Pointing device  90  is connected to the computer  20  and powered by a standard USB cable  902 . Cable  902  extends from device  90  and terminates with a standard USB plug  903  that is inserted into a USB port  92  on either side of the computer  20 . The USB port recognizes the interface of device  90 , and automatically configures it either for a right or left-hand mouse as a function of the side of the computer USB plug  903  is inserted. The handedness of device  90  can also be independently set as an option in the application software. 
   Alternatively, cable  902  can include a USB connector interface at device  90  wherein cable  902  includes either a standard or mini USB connector  904  at the device  90  interface end that interfaces with a like USB connector  914  on device  90 . 
     FIGS. 12-13  illustrate an ergonomic embodiment  1200  of a pointing device according to the present invention. Pointing device  1200  includes a sliding plate  1201  and has the same surface appearance, controls, internal construction, and software functions as device  90  ( FIG. 11 ). Device  1200  incorporates a more ergonomic design than the pointing device  90  described above. 
   Device  1200  includes a top section  1202  and a bottom section  1203  that forms leg supporting midsections  1206 ,  1207  above the surface on which device  1200  rests. Top and bottom sections  1202 ,  1203  are hinged relative to mid-sections  1206 ,  1207  enabling device  1200  to be folded into a compact form factor. Mid-section  1206  forms a palm rest for the user on which the user may rest the palm of the hand operating device  1200 . Mid-section slides on rail  1205  mounted under mid-section  1207  thereby enabling bottom mid-section  1206  to be shortened or lengthened to better fit the size of the user&#39;s hand when in use. When unfolded, the ergonomic shape allows the user&#39;s wrist to rest thereon in a comfortable position. 
   Pointing device  1200  is connected to a computer and powered by a standard USB cable  1220  that terminates in a male USB plug  1222 . USB plug  1222  may be inserted into a USB port on either side of the portable computer. The USB port recognizes the interface of device  1200  and automatically configures for either right- or left-handed operation. 
   The above description is considered that of the preferred embodiments only. Modifications of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and are not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the doctrine of equivalents.