PATENT DOCUMENT

Publication Number: US-11886699-B2
Application Number: US-202217820368-A
Country: US
Kind Code: B2

Title: Selective rejection of touch contacts in an edge region of a touch surface

Abstract:
The selective rejection of touch contacts in an edge region of a touch sensor panel is disclosed. In addition, by providing certain exceptions to the rejection of edge contacts, the functionality of the touch sensor panel can be maximized. Contacts in edge bands around the perimeter of a touch sensor panel can be ignored. However, if a contact in the edge band moves beyond a threshold distance or speed, it can be recognized as part of a gesture. To accommodate different finger sizes, the size of the edge band can be modified based on the identification of the finger or thumb. Furthermore, if contacts in the center region of a touch sensor panel track the movement of contacts in the edge band, the contacts in the edge band can be recognized as part of a gesture.

Claims:
What is claimed is: 
     
       1. A method for selectively rejecting contacts on a touch sensor panel, comprising:
 designating one or more regions along one or more edges of the touch sensor panel as contact rejection regions; 
 detecting a first contact having first movement within the one or more contact rejection regions; 
 detecting a second contact having second movement within a center region of the touch sensor panel; and 
 in accordance with a determination that the first movement of the first contact is synchronous with the second movement of the second contact, recognizing the first contact and the second contact as part of a single gesture. 
 
     
     
       2. The method of  claim 1 , further comprising:
 in accordance with a determination that the first movement of the first contact is not synchronous with the second movement of the second contact, rejecting the first contact as a touch. 
 
     
     
       3. The method of  claim 1 , wherein the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that the first contact is detected at least partially overlapping in time with the detected second contact. 
     
     
       4. The method of  claim 1 , wherein the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that a first centroid of the first contact and a second centroid of the second contact are moving at the same speed. 
     
     
       5. The method of  claim 1 , wherein the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that a first centroid of the first contact and a second centroid of the second contact are moving in the same direction. 
     
     
       6. The method of  claim 1 , wherein the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that the first contact touched down at the same time that the second contact touched down. 
     
     
       7. The method of  claim 1 , wherein the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that the second movement of the second contact tracks the first movement of the first contact. 
     
     
       8. A non-transitory computer-readable storage medium storing program code for selectively rejecting contacts on a touch sensor panel, the program code for causing performance of a method comprising:
 designating one or more regions along one or more edges of the touch sensor panel as contact rejection regions; 
 detecting a first contact having first movement within the one or more contact rejection regions; 
 detecting a second contact having second movement within a center region of the touch sensor panel; and 
 in accordance with a determination that the first movement of the first contact is synchronous with the second movement of the second contact, recognizing the first contact and the second contact as part of a single gesture. 
 
     
     
       9. The non-transitory computer-readable storage medium of  claim 8 , the program code further for causing performance of the method comprising:
 in accordance with a determination that the first movement of the first contact is not synchronous with the second movement of the second contact, rejecting the first contact as a touch. 
 
     
     
       10. The non-transitory computer-readable storage medium of  claim 8 , wherein:
 the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that the first contact is detected at least partially overlapping in time with the detected second contact. 
 
     
     
       11. The non-transitory computer-readable storage medium of  claim 8 , wherein:
 the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that a first centroid of the first contact and a second centroid of the second contact are moving at the same speed. 
 
     
     
       12. The non-transitory computer-readable storage medium of  claim 8 , wherein:
 the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that a first centroid of the first contact and a second centroid of the second contact are moving in the same direction. 
 
     
     
       13. The non-transitory computer-readable storage medium of  claim 8 , wherein:
 the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that the first contact touched down at the same time that the second contact touched down. 
 
     
     
       14. The non-transitory computer-readable storage medium of  claim 8 , wherein:
 the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that the second movement of the second contact tracks the first movement of the first contact. 
 
     
     
       15. A computing device including a computer-readable storage medium storing program code for selectively rejecting contacts on a touch sensor panel, the program code for causing performance of a method comprising:
 designating one or more regions along one or more edges of the touch sensor panel as contact rejection regions; 
 detecting a first contact having first movement within the one or more contact rejection regions; 
 detecting a second contact having second movement within a center region of the touch sensor panel; and 
 in accordance with a determination that the first movement of the first contact is synchronous with the second movement of the second contact, recognizing the first contact and the second contact as part of a single gesture. 
 
     
     
       16. The computing device of  claim 15 , the program code further for causing performance of the method comprising:
 in accordance with a determination that the first movement of the first contact is not synchronous with the second movement of the second contact, rejecting the first contact as a touch. 
 
     
     
       17. The computing device of  claim 15 , wherein:
 the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that the first contact is detected at least partially overlapping in time with the detected second contact. 
 
     
     
       18. The computing device of  claim 15 , wherein:
 the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that a first centroid of the first contact and a second centroid of the second contact are moving at the same speed. 
 
     
     
       19. The computing device of  claim 15 , wherein:
 the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that a first centroid of the first contact and a second centroid of the second contact are moving in the same direction. 
 
     
     
       20. The computing device of  claim 15 , wherein:
 the determination that the first movement of the first contact is synchronous with the second movement of the second contact includes a determination that the first contact touched down at the same time that the second contact touched down.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 16/993,134, filed Aug. 13, 2020 (U.S. Publication No. 2020/0371688), which is a continuation of U.S. application Ser. No. 15/880,362, filed Jan. 25, 2018 and issued on Aug. 18, 2020 as U.S. Pat. No. 10,747,428, which is a continuation of U.S. application Ser. No. 14/711,626, filed May 13, 2015 and issued on Feb. 13, 2018 as U.S. Pat. No. 9,891,732, which is a continuation of U.S. application Ser. No. 13/250,955, filed Sep. 30, 2011 and issued on May 26, 2015 as U.S. Pat. No. 9,041,663, which is a continuation of U.S. application Ser. No. 12/242,772 (now abandoned), filed Sep. 30, 2008, which claims the benefit of U.S. Provisional Application No. 61/019,220 filed on Jan. 4, 2008, the contents of which are incorporated herein by reference in their entirety for all purposes. 
    
    
     FIELD OF THE INVENTION 
     This relates generally to input devices for computing systems, and more particularly, to the selective rejection of touch contacts in an edge region of a touch sensor panel. 
     BACKGROUND OF THE INVENTION 
     Many types of input devices are presently available for performing operations in a computing system, such as buttons or keys, mice, trackballs, touch sensor panels, joysticks, touch screens and the like. Touch screens, in particular, are becoming increasingly popular because of their ease and versatility of operation as well as their declining price. Touch screens can include a touch sensor panel, which can be a clear panel with a touch-sensitive surface. The touch sensor panel can be positioned in front of a display screen so that the touch-sensitive surface covers the viewable area of the display screen. Touch screens can allow a user to make selections and move a cursor by simply touching the display screen via a finger or stylus. In general, the touch screen can recognize the touch and position of the touch on the display screen, and the computing system can interpret the touch and thereafter perform an action based on the touch event. 
     Touch sensor panels can be implemented as an array of pixels formed by multiple drive lines (e.g. rows) crossing over multiple sense lines (e.g. columns), where the drive and sense lines are separated by a dielectric material. An example of such a touch sensor panel is described in Applicant&#39;s co-pending U.S. application Ser. No. 11/650,049 entitled “Double-Sided Touch Sensitive Panel and Flex Circuit Bonding,” (U.S. Patent Application Publication No. 2008/0158181), filed on Jan. 3, 2007, the contents of which are incorporated by reference herein. 
     However, fingers and palms inadvertently in close proximity with a touch sensor panel can cause unintended gestures to be recognized and processed. These inadvertent touches can often occur when the touch sensor panel is separate from but adjacent to other input devices being used, such as a conventional keyboard or mechanical buttons or bars. Additionally, when the touch sensor panel itself is being used, fingers such as those used for stabilization of the hand (but not part of the gesture) or holding the device can accidentally touch the edges of the panel and be detected. 
     SUMMARY OF THE INVENTION 
     This relates to the selective rejection of touch contacts (touch events) in an edge region of a touch sensor panel to minimize unintended operations. In addition, by providing certain exceptions to the rejection of edge contacts, the functionality of the touch sensor panel can be maximized. 
     In some embodiments, contacts in edge bands around the perimeter of a touch sensor panel can simply be ignored. However, there can be a number of exceptions to edge rejection. For example, contacts in both the center area and the edge band can cause the contact in the edge band to be recognized as part of a gesture in certain circumstances. In other embodiments, if the contact in the edge band is stationary, it can be ignored. However if the contact in the edge band moves beyond a threshold distance or speed, it can then be recognized as part of a gesture. 
     Similarly, in trackpad embodiments, contacts within a bottom region of the trackpad can be ignored if stationary, but recognized as part of a gesture if moving. To accommodate different finger sizes, the size of one or more regions (e.g. the bottom or top region) can be modified based on an identification of the finger or thumb. 
     If contacts in the center or main region of a touch sensor panel track the movement of contacts in the edge band or bottom region, the contacts in the edge band or bottom region may not be ignored, but instead be recognized as part of a gesture. In addition, contacts appearing in the edge band or bottom region during the recognition of gestures in the center or main regions of a touch sensor panel can be recognized as part of the gesture or as a control input to implement operations such as drag lock or conversion of gestures. In other embodiments, two or more contacts detected in an edge band can be interpreted as a gesture if the contacts have a certain predetermined spacing (e.g., their centroids have an x-direction separation of between 1-3 cm). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1   a    illustrates an exemplary touch sensor panel implementing edge rejection according to one embodiment of this invention. 
         FIG.  1 B  illustrates an exemplary touch sensor panel implementing an exception to edge rejection according to one embodiment of this invention. 
         FIG.  2    illustrates an exemplary trackpad implementing edge rejection according to one embodiment of this invention. 
         FIG.  3   a    illustrates an exemplary touch sensor panel implementing edge rejection and exceptions to edge rejection according to one embodiment of this invention. 
         FIG.  3   b    illustrates an exemplary touch sensor panel implementing edge rejection exceptions based on the recognition of two contacts having synchronized movements according to one embodiment of this invention. 
         FIG.  4    illustrates an exemplary touch sensor panel implementing exceptions to edge rejection in order to provide a drag lock function according to one embodiment of this invention. 
         FIG.  5   a    illustrates an exemplary touch sensor panel implementing exceptions to edge rejection based on contacts in an edge region and a main region according to one embodiment of this invention. 
         FIG.  5   b    illustrates an exemplary touch sensor panel implementing exceptions to edge rejection in order to allow a pinching gesture according to one embodiment of this invention. 
         FIGS.  5   c  and  5   d    illustrate an exemplary exception to edge rejection and an example of edge rejection, respectively, according to embodiments of the invention. 
         FIG.  6    illustrates an exemplary touch sensor panel employing edge rejection with a variable width edge band according to one embodiment of this invention. 
         FIG.  7   a    illustrates an exemplary trackpad  700  having an integrated pick button and click regions according to embodiments of the invention. 
         FIG.  7   b    illustrates an exemplary extension of the embodiment of  FIG.  7   a    in which more than two click regions can be defined according to embodiments of the invention. 
         FIG.  8    illustrates an exemplary computing system operable with a touch sensor panel to implement edge rejection and exceptions to edge rejection according to one embodiment of this invention. 
         FIG.  9   a    illustrates an exemplary mobile telephone that can include a touch sensor panel and computing system for implementing edge rejection and exceptions to edge rejection according to one embodiment of this invention. 
         FIG.  9   b    illustrates an exemplary digital media player that can include a touch sensor panel and computing system for implementing edge rejection and exceptions to edge rejection according to one embodiment of this invention. 
         FIG.  9   c    illustrates an exemplary personal computer that can include a touch sensor panel and computing system for implementing edge rejection and exceptions to edge rejection according to one embodiment of this invention. 
         FIG.  10    is a simplified diagram of an exemplary touch pad and display according to one embodiment of this invention. 
         FIG.  11    is a perspective view of an exemplary input device according to one embodiment of this invention. 
         FIGS.  12 A,  12 B,  12 C and  12 D  are simplified side views of an exemplary input device having a button touch pad according to one embodiment of this invention. 
         FIG.  13    is a simplified block diagram of an exemplary input device connected to a computing device according to one embodiment of this invention. 
         FIG.  14    is a side view, in cross section, of an exemplary input device according to one embodiment of this invention. 
         FIG.  15    is another side view, in cross section, of the exemplary input device of  FIG.  12    according to one embodiment of this invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the following description of preferred embodiments, reference is made to the accompanying drawings in which it is shown by way of illustration specific embodiments in which the invention can be practiced. It is to be understood that other embodiments can be used and structural changes can be made without departing from the scope of the embodiments of this invention. 
     This relates to the selective rejection of touch contacts in an edge region of a touch sensor panel to minimize unintended operations. In addition, by providing certain exceptions to the rejection of edge contacts, the functionality of the touch sensor panel can be maximized. 
       FIG.  1   a    illustrates exemplary touch sensor panel  100  implementing edge rejection according to embodiments of the invention. Edge band  102  (contact rejection region) can be created in an outer boundary of touch sensor panel  100 , surrounding center area  104 . If all contacts (e.g. fingers or palms) are detected in edge band  102 , the contacts can be ignored. In the example of  FIG.  1   a   , because touch images  106  and  108  have centroids  110  and  112 , respectively, located in edge band  102 , the contacts can be ignored. 
       FIG.  1 B  illustrates a second scenario that can occur on exemplary touch sensor panel  100  according to embodiments of the invention. In the example of  FIG.  1 B , if contact  114  is detected in center area  104  along with contact  116  in edge band  102 , a contact can be recognized in both the center area and the edge band. The recognition of the edge contact in this scenario in accordance with the aforementioned criteria (rejection or recognition criteria) can prevent intended gestures such as pinching gestures with contacts starting in an edge band from being ignored. 
     However, when fingers are used to perform an operation such as pointing in center area  104 , a so-called “pinky” or other finger inadvertently placed in edge band  102  can be recognized, and an unintended gesture can be performed instead of the pointing gesture. Therefore, in other embodiments of the invention, if contacts  114  and  116  are detected at both center area  104  and edge band  102 , and if centroid  118  of edge contact  116  does not move more than a threshold amount (e.g. 1 mm), it can be ignored. However, if edge contact  116  moves more than the threshold amount in any direction (even if there is no other finger detected in the center area), it can be recognized and become a trackable contact that can be part of a gesture. This recognition also allows for tracking operations to be performed within edge band  102 . 
       FIG.  2    illustrates an exemplary touch sensor panel in the form of trackpad  200  implementing edge rejection according to embodiments of the invention. In the example of  FIG.  2   , adjacent to trackpad  200  is a conventional keyboard space bar  202  and mechanical pick button  204 . Exemplary inadvertent touches illustrated in  FIG.  2    can include thumb  206  resting on space bar  202  but also inadvertently resting on trackpad  200 . The detected contact at  208  can be ignored so that clicks or other actions are not accidentally generated. In addition, pinky  210  inadvertently touching trackpad  200  can be ignored, and thumb  212  resting on pick button  204  but also overhanging the bottom of the trackpad at  214  can be ignored to avoid it being recognized as part of an unintended pinch gesture. 
       FIG.  3   a    illustrates another exemplary touch sensor panel  300  implementing edge rejection according to embodiments of the invention. In the example of  FIG.  3   a   , touch sensor panel  300  can include a bottom region  302  that can normally be reserved for performing certain non-gesture actions. For example, finger taps in bottom region  302  can be interpreted as a “click” or selection function. Thus, contacts in bottom region  302  can normally be ignored for all purposes except these functions. Nevertheless, it can be desirable to have contacts in bottom region  302  recognized as part of a gesture in certain circumstances. Therefore, according to some embodiments of the invention, in accordance with rejection or recognition criteria, contacts  304  identified as a finger (i.e. a non-concentric image of touch of a certain threshold size) occurring within the bottom region can be ignored if centroid  306  is stationary, but can be recognized as part of a gesture if the centroid is not stationary. Identification of touch events is disclosed in U.S. Pat. No. 6,323,846 entitled “Method and Apparatus for Integrating Manual Input,” the contents of which are incorporated herein by reference in its entirety for all purposes. Stationary, as defined herein, is when the centroid moves less than a threshold amount from a computed centroid center, or remains below some speed threshold. If the difference between an instantaneous position and a low pass filter (LPF) averaged position value exceeds a certain threshold value, the centroid can be considered in motion and no longer stationary. Using this criteria, contacts with slow drifting or rolling motions can be ignored, but faster drifts can cause the contact to be recognized as part of a gesture. 
     In another embodiment of the invention, the size of bottom region  302  or top region  316  (or any other edge region) can dynamically change based on a determination that a contact was caused by a particular finger. For example, if a thumb is detected in bottom region  302 , then based on the radius of the touch area, demarcation line  308  defining the bottom region can be moved upward to increase the size of the bottom region. However, if a finger is detected in bottom region  302 , demarcation line  308  can be moved downward to decrease the size of the bottom region. Similar adjustments can be made for the top region  316 , or any other edge regions (e.g. left or right side regions). 
     As described above, contacts in bottom region  302  can be treated as non-contacts independent from main region  310 , although in some embodiments contacts in the bottom region can be detected and used in conjunction with contacts in the main area. For example, if the contacts in bottom region  302  move in a manner that is synchronous with or otherwise associated with movements in main region  310 , the contacts in the bottom region can be recognized along with the contacts in the main region as part of the gesture. 
       FIG.  3   b    illustrates the recognition of two contacts having synchronized movements according to embodiments of the invention. In the example of  FIG.  3   b   , if contacts  304  and  312  move in a substantially synchronous manner with respect to each other, contact  304  can be recognized along with contact  312  as part of a gesture. Otherwise, contact  304  can be ignored. Two contacts moving “synchronously,” as defined herein, can include centroids moving at approximately the same speed and/or direction (either X and Y components together, or only the X or only the Y components). In other embodiments, the synchronized movements of two contacts can include touching down synchronously. Thus, even though one of the two contacts may touch down within an edge band, if it touches down at substantially the same time as a contact touching down in the main region  310 , the two contacts can be recognized as part of a gesture. 
       FIG.  4    illustrates another exemplary exception to edge rejection according to embodiments of the invention. In the example of  FIG.  4   , at location (1), contacts  416  and  418  caused by two fingers within main region  410  move to the left as part of an intended drag operation. At location (2), contacts  416  and  418  have reached the leftmost edge of main region  410 . If the drag operation is to continue, at location (3) a thumb can be placed down in bottom region  402 , causing contact  420  to appear, In this embodiment, instead of being ignored, the two preexisting contacts  416  and  418  cause contact  420  to be recognized as a so-called “drag lock” feature of the gesture. With the drag lock in place, the two fingers can be temporarily lifted off the touch sensor panel and touched down again towards the center of main region  410  at location (4), where the leftward drag operation can continue. It should be understood that this edge rejection exception can also be applied to other gestures in main region  410 , wherein other contacts in the main region, optionally accompanied by movement, can cause subsequent contacts in bottom region  402  to be recognized as part of a gesture. Alternatively, the subsequent contact in bottom region  402  can cause a change in the gesture recognized in main region  410 . For example, a pointing function in main region  410  can be converted to a drag function as soon as a contact is either detected in, or removed from, bottom region  402 . 
       FIG.  5   a    illustrates another exemplary exception to edge rejection according to embodiments of the invention. In  FIG.  5   a   , stationary thumb  524  detected in bottom region  502  plus finger  522  detected in main region  510  can be recognized as the start of a finger drag gesture, and can remain so as long as the finger moves while the thumb remains stationary. 
       FIG.  5   b    illustrates yet another exemplary exception to edge rejection according to embodiments of the invention. In  FIG.  5   b   , thumb  524  detected in bottom region plus finger  522  detected in main region  510  moving simultaneously towards each other can be recognized as the start of a pinch gesture. 
       FIG.  5   c    illustrates another exemplary exception to edge rejection according to embodiments of the invention. In  FIG.  5   c   , two or more contacts  528  detected in an edge band (e.g. bottom region  502 ) can be interpreted as a gesture if the contacts have a certain predetermined spacing (e.g., the contacts have centroids with an x-direction separation of between 1-3 cm). In this manner, for example, two fingers starting a scroll in the bottom region  502  (and then moving upwards as indicated at  530 ) will immediately start the gesture instead of being ignored as edge straddles. 
       FIG.  5   d    illustrates, however, that in certain regions, two contacts occurring in an edge band can be ignored. In the example of  FIG.  5   d   , two contacts  532  in side region  526  occurring as a result of an edge-straddling palm can be ignored to avoid initiating an inadvertent scroll. 
       FIG.  6    illustrates an exemplary touch sensor panel  600  employing edge rejection with a variable width edge band  602  according to embodiments of the invention. In the example of  FIG.  6   , the width of edge band  602  can be dependent on a major radius of contact  606 . A large major radius (above a certain threshold) of a contact whose centroid  610  is located within edge band  602  can cause the edge band to be larger in order to better ignore a thumb as opposed to a fingertip. The amount or percentage of the major radius above the threshold can be used to scale up edge band  602 . Alternatively, the width of edge band  602  may not be dependent on the major radius, but instead can be based on the identification of a particular finger type. In some embodiments, the variable width edge band  602  may have a non-uniform width, and may be wider along one or more edges of the touch sensor panel and narrower along one or more different edges of the touch sensor panel. For example, a bottom region  602   a  of edge band  602  may have a width that is greater than that of side regions  602   b  and  602   c  and top region  602   d.    
       FIG.  7   a    illustrates an exemplary trackpad  700  having an integrated pick button according to embodiments of the invention. In the example of  FIG.  7   a   , the trackpad  700  can be mechanically actuated by pushing on the trackpad to generate a “click” input to implement a mechanical pick button. Trackpads with integrated pick buttons are described in  FIGS.  10 - 15    below. 
     In the trackpad  700  of  FIG.  7   a   , sufficient pressure anywhere on the surface of the trackpad can cause the click to be generated, and thus the click itself is not determinative of the location of the click. Therefore, according to embodiments of the invention, touch sensing on the trackpad  700  can be used to determine how a click should be interpreted. When a mechanical click is detected, the interpretation of the click and the resulting functionality initiated can depend on where a touch was detected on the trackpad. In the example embodiment of  FIG.  7   a   , the trackpad  700  is partitioned into a primary click region  702  and secondary click region  704 . When a touch is detected on the primary click region  702  along with a mechanical click from the trackpad, a left-click action can be initiated, for example. Similarly, when a touch is detected on the secondary click region  704  along with a mechanical click from the trackpad, a right-click action can be initiated, for example. The partitioning of the trackpad  700  can be implemented in firmware. 
     The example of  FIG.  7   a    shows equal-sized primary and secondary click regions  702  and  704 . However, in other embodiments, the size or area of the click regions may be unequal to account for intended usage patterns and avoid misinterpreted clicks. For example, because the secondary click region  704  may be less frequently used than the primary click region  702 , the secondary click region may be made smaller and/or located in a region less likely to be clicked upon, such as the lower right corner of the trackpad  700 . 
       FIG.  7   b    illustrates an exemplary extension of the embodiment of  FIG.  7   a    in which more than two click regions can be defined. In the example of  FIG.  7   b   , in addition to primary and secondary click regions  702  and  704 , a number of function key click regions  706 ,  708  and  710  can be defined. A click of the trackpad  700  along with a touch in any of these regions can initiate a corresponding action. Those skilled in the art will understand that because the partitions are implemented in firmware, any number of regions, in any number of configurations, can also be employed. In further embodiments, these regions can dynamically change in accordance with a particular usage of the computing device (e.g., in accordance with the application being executed or the user interface being displayed). 
     Embodiments of the invention described above can be implemented using touch sensor panels of the types described in U.S. application Ser. No. 11/650,049 entitled “Double-Sided Touch Sensitive Panel and Flex Circuit Bonding,” filed Jan. 3, 2007 (U.S. Patent Application Publication No. 2008/0158181). Sense channels of the types described in U.S. application Ser. No. 11/649,998 entitled “Proximity and Multi-Touch Sensor Detection and Demodulation,” filed Jan. 3, 2007 (U.S. Patent Application Publication No. 2008/0158172) can be used to detect touch and hover events. The resulting image of touch can be further processed to determine the location of the touch events, the identification of finger contacts, and the identification of gestures as described in U.S. application Ser. No. 11/428,522 entitled “Identifying Contacts on a Touch Surface,” filed Jul. 3, 2006 (U.S. Patent Application Publication No. 2006/0238522), U.S. application Ser. No. 11/756,211 entitled “Multi-touch Input Discrimination,” filed May 31, 2007 (U.S. Patent Application Publication No. 2008/0158185) and U.S. application Ser. No. 10/903,964 entitled “Gestures for Touch Sensitive Input Devices,” filed Jul. 30, 2004 (U.S. Patent Application Publication No. 2006/0026521). All of the preceding applications referred to in this paragraph are incorporated by reference herein in their entirety for all purposes. 
       FIG.  8    illustrates exemplary computing system  800  that can include one or more of the embodiments of the invention described above. Computing system  800  can include one or more panel processors  802  and peripherals  804 , and panel subsystem  806 . Peripherals  804  can include, but are not limited to, random access memory (RAM) or other types of memory or storage, watchdog timers and the like. Panel subsystem  806  can include, but is not limited to, one or more sense channels  808 , channel scan logic  810  and driver logic  814 . Channel scan logic  810  can access RAM  812 , autonomously read data from the sense channels and provide control for the sense channels. In addition, channel scan logic  810  can control driver logic  814  to generate stimulation signals  816  at various frequencies and phases that can be selectively applied to drive lines of touch sensor panel  824  at a voltage established by charge pump  815 . In some embodiments, panel subsystem  806 , panel processor  802  and peripherals  804  can be integrated into a single application specific integrated circuit (ASIC). 
     Touch sensor panel  824  can include a capacitive sensing medium having a plurality of drive lines and a plurality of sense lines, although other sensing media can also be used. Each intersection, adjacency or near-adjacency of drive and sense lines can represent a capacitive sensing node and can be viewed as picture element (pixel)  826 , which can be particularly useful when touch sensor panel  824  is viewed as capturing an “image” of touch. (In other words, after panel subsystem  806  has determined whether a touch event has been detected at each touch sensor in the touch sensor panel, the pattern of touch sensors in the multi-touch panel at which a touch event occurred can be viewed as an “image” of touch (e.g. a pattern of fingers touching the panel).) Each sense line of touch sensor panel  824  can drive sense channel  808  (also referred to herein as an event detection and demodulation circuit) in panel subsystem  806 . 
     Computing system  800  can also include host processor  828  for receiving outputs from panel processor  802  and performing actions based on the outputs that can include, but are not limited to, moving an object such as a cursor or pointer, scrolling or panning, adjusting control settings, opening a file or document, viewing a menu, making a selection, executing instructions, operating a peripheral device coupled to the host device, answering a telephone call, placing a telephone call, terminating a telephone call, changing the volume or audio settings, storing information related to telephone communications such as addresses, frequently dialed numbers, received calls, missed calls, logging onto a computer or a computer network, permitting authorized individuals access to restricted areas of the computer or computer network, loading a user profile associated with a user&#39;s preferred arrangement of the computer desktop, permitting access to web content, launching a particular program, encrypting or decoding a message, and/or the like. Host processor  828  can also perform additional functions that may not be related to panel processing, and can be coupled to program storage  832  and display device  830  such as an LCD display for providing a UI to a user of the device. Display device  830  together with touch sensor panel  824 , when located partially or entirely under the touch sensor panel, or partially or entirely integrated with the touch sensor panel, can form touch screen  818 . 
     Note that one or more of the functions described above can be performed by firmware stored in memory (e.g. one of the peripherals  804  in  FIG.  8   ) and executed by panel processor  802 , or stored in program storage  832  and executed by host processor  828 . The firmware can also be stored and/or transported within any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. In the context of this document, a “computer-readable storage medium” can be any storage medium that can contain or store the program for use by or in connection with the instruction execution system, apparatus, or device. The computer readable storage medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus or device, a portable computer diskette (magnetic), a random access memory (RAM) (magnetic), a read-only memory (ROM) (magnetic), an erasable programmable read-only memory (EPROM) (magnetic), a portable optical disc such a CD, CD-R, CD-RW, DVD, DVD-R, or DVD-RW, or flash memory such as compact flash cards, secured digital cards, USB memory devices, memory sticks, and the like. 
     The firmware can also be propagated within any transport medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. In the context of this document, a “transport medium” can be any medium that can communicate, propagate or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The transport readable medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic or infrared wired or wireless propagation medium. 
       FIG.  9   a    illustrates exemplary mobile telephone  936  that can include touch sensor panel  924  and computing system  942  for implementing edge rejection and the edge rejection exceptions described above according to embodiments of the invention.  FIG.  9   b    illustrates exemplary digital media player  940  that can include touch sensor panel  924  and computing system  942  for implementing edge rejection and the edge rejection exceptions described above according to embodiments of the invention.  FIG.  9   c    illustrates exemplary personal computer  944  that can include touch sensor panel (trackpad)  924  and computing system  942  for implementing edge rejection and the edge rejection exceptions described above according to embodiments of the invention. The mobile telephone, media player, and personal computer of  FIGS.  9   a ,  9   b  and  9   c    can advantageously benefit from the edge rejection and the edge rejection exceptions described above because implementation of these features can minimize unintended operations while providing maximum functionality. 
     As discussed above, some embodiments of the invention are directed to trackpads with integrated pick buttons. One example of a trackpad with an integrated pick button is described below with reference to  FIGS.  10 - 15   . However, it should be understood that other trackpads or input devices having integrated pick buttons also fall within the scope of embodiments of the present invention. 
       FIG.  10    is a simplified diagram of an exemplary touch pad and display according to embodiments of the invention. In the example of  FIG.  10   , a touch-sensitive track pad  10  can be a small (often rectangular) area that includes a protective/cosmetic shield  12  and a plurality of electrodes  14  disposed underneath the protective shield  12 . Electrodes  14  may be located on a circuit board, for example a printed circuit board (PCB). For ease of discussion, a portion of the protective shield  12  has been removed to show the electrodes  14 . Different electrodes  14  or combinations thereof can represent different x, y positions. In one configuration, as a finger  16  (or alternatively a stylus, not shown) approaches the electrode grid  14 , the finger may form a capacitance with one or more electrodes proximate to the finger or may change existing capacitances between one or more such electrodes. The circuit board/sensing electronics (not shown) measures such capacitance changes and produces an input signal  18  which is sent to a host device  20  (e.g., a computing device) having a display screen  22 . The input signal  18  is used to control the movement of a cursor  24  on a display screen  22 . As shown, the input pointer moves in a similar x, y direction as the detected x, y finger motion. 
       FIG.  11    is a simplified perspective view of an exemplary input device according to embodiments of the invention. The input device  30  is generally configured to send information or data to an electronic device (not shown) in order to perform an action on a display screen (e.g., via a graphical user interface (GUI))—for example, moving an input pointer, making a selection, providing instructions, etc. The input device may interact with the electronic device through a wired (e.g., cable/connector) or wireless connection (e.g., IR, bluetooth, etc.). 
     The input device  30  may be a stand alone unit or it may be integrated into the electronic device. When in a stand alone unit, the input device typically has its own enclosure. When integrated with an electronic device, the input device typically uses the enclosure of the electronic device. In either case, the input device may be structurally coupled to the enclosure as for example through screws, snaps, retainers, adhesives and the like. In some cases, the input device may be removably coupled to the electronic device as for example through a docking station. The electronic device to which the input device is coupled may correspond to any consumer related electronic product. By way of example, the electronic device may correspond to a computer such as a desktop computer, laptop computer or PDA, a media player such as a music player, a communication device such as a mobile phone, another input device such as a keyboard, and the like. 
     As shown in  FIG.  11   , the input device  30  includes a frame  32  (or support structure) and a track pad  34 . The frame  32  provides a structure for supporting the components of the input device. The frame  32 , in the form of a housing, may also enclose or contain the components of the input device. The components, which include the track pad  34 , may correspond to electrical, optical and/or mechanical components for operating the input device  30 . 
     Track pad  34  provides an intuitive interface configured to provide one or more control functions for controlling various applications associated with the electronic device to which it is attached. By way of example, the touch initiated control function may be used to move an object or perform an action on the display screen or to make selections or issue commands associated with operating the electronic device. In order to implement the touch initiated control function, the track pad  34  may be arranged to receive input from a finger (or object) moving across the surface of the track pad  34  (e.g., linearly, radially, angular, etc.), from a finger holding a particular position on the track pad  34  and/or by a finger tapping on a particular position of the track pad  34 . As should be appreciated, the touch pad  34  provides easy one-handed operation, i.e., lets a user interact with the electronic device with one or more fingers. 
     The track pad  34  may be widely varied. For example, the touch pad  34  may be a conventional track pad based on the Cartesian coordinate system, or the track pad  34  may be a touch pad based on a polar coordinate system. An example of a touch pad based on polar coordinates may be found in U.S. Pat. No. 7,046,230 to Zadesky et al., entitled “TOUCH PAD FOR HANDHELD DEVICE”, filed Jul. 1, 2002, which is hereby incorporated by reference herein in its entirety for all purposes. 
     The track pad  34  may be used in a relative or absolute mode. In absolute mode, the track pad  34  reports the absolute coordinates of where it is being touched (for example x, y in the case of the Cartesian coordinate system or (r, θ) in the case of the polar coordinate system). In relative mode, the track pad  34  reports the direction and/or distance of change (for example, left/right, up/down, and the like). In most cases, the signals produced by the track pad  34  direct motion on the display screen in a direction similar to the direction of the finger as it is moved across the surface of the track pad  34 . 
     The shape of the track pad  34  may be widely varied. For example, the track pad  34  may be circular, oval, square, rectangular, triangular, and the like. In general, the outer perimeter of the track pad  34  defines the working boundary of the track pad  34 . In the illustrated embodiment, the track pad is rectangular. Rectangular track pads are common on laptop computers. Circular track pads allow a user to continuously swirl a finger in a free manner, i.e., the finger can be rotated through 360 degrees of rotation without stopping. Furthermore, the user can rotate his or her finger tangentially from all sides thus giving it more range of finger positions. Both of these features may help when performing a scrolling function, making circular track pads advantageous for use with portable media players (e.g., iPod media players produced by Apple Inc. of Cupertino, CA). Furthermore, the size of the track pad  34  generally corresponds to a size that allows them to be easily manipulated by a user (e.g., the size of a finger tip or larger). 
     The track pad  34 , which generally takes the form of a rigid planar platform, includes a touchable outer track surface  36  for receiving a finger (or object) for manipulation of the track pad. Although not shown in  FIG.  11   , beneath the touchable outer track surface  36  is a sensor arrangement that is sensitive to such things as the pressure and/or motion of a finger thereon. The sensor arrangement typically includes a plurality of sensors that are configured to activate as the finger sits on, taps on or passes over them. In the simplest case, an electrical signal is produced each time the finger is positioned over a sensor. The number of signals in a given time frame may indicate location, direction, speed, and acceleration of the finger on the track pad  34 , i.e., the more signals, the more the user moved his finger. In most cases, the signals are monitored by an electronic interface that converts the number, combination and frequency of the signals into location, direction, speed and acceleration information. This information may then be used by the electronic device to perform the desired control function on the display screen. The sensor arrangement may be widely varied. By way of example, the sensors may be based on resistive sensing, surface acoustic wave sensing, pressure sensing (e.g., strain gauge), infra red sensing, optical sensing, dispersive signal technology, acoustic pulse recognition, capacitive sensing and the like. 
     In the illustrated embodiment, the track pad  34  is based on capacitive sensing. As is generally well known, a capacitance-based track pad is arranged to detect changes in capacitance as the user moves an object such as a finger around the track pad. In most cases, the capacitive track pad includes a protective shield, one or more electrode layers, a circuit board and associated electronics including an application specific integrated circuit (ASIC). The protective shield is placed over the electrodes; the electrodes are mounted on the top surface of the circuit board; and the ASIC is mounted on the bottom surface of the circuit board. The protective shield serves to protect the underlayers and to provide a surface for allowing a finger to slide thereon. The surface is generally smooth so that the finger does not stick to it when moved. The protective shield also provides an insulating layer between the finger and the electrode layers. The electrode layer includes a plurality of spatially distinct electrodes. Any suitable number of electrodes may be used. In most cases, it would be desirable to increase the number of electrodes so as to provide higher resolution, i.e., more information can be used for things such as acceleration. 
     Capacitive sensing works according to the principals of capacitance. As should be appreciated, whenever two electrically conductive members come close to one another without actually touching, their electric fields interact to form capacitance. In the configuration discussed above, the first electrically conductive member is one or more of the electrodes and the second electrically conductive member is, for example, the finger of the user. Accordingly, as the finger approaches the touch pad, a tiny capacitance forms between the finger and the electrodes in close proximity to the finger. The capacitance in each of the electrodes is measured by an ASIC located on the backside of the circuit board. By detecting changes in capacitance at each of the electrodes, the ASIC can determine the location, direction, speed and acceleration of the finger as it is moved across the touch pad. The ASIC can also report this information in a form that can be used by the electronic device. 
     In accordance with one embodiment, track pad  34  is movable relative to frame  32  so as to initiate another set of signals (other than just tracking signals). By way of example, track pad  34  in the form of the rigid planar platform may rotate, pivot, slide, translate, flex and/or the like relative to frame  32 . Track pad  34  may be coupled to frame  32  and/or it may be movably restrained by frame  32 . By way of example, track pad  34  may be coupled to frame  32  through screws, axels, pin joints, slider joints, ball and socket joints, flexure joints, magnets, cushions and/or the like. Track pad  34  may also float within a space of the frame (e.g., gimbal). It should be noted that the input device  30  may additionally include a combination of joints such as a pivot/translating joint, pivot/flexure joint, pivot/ball and socket joint, translating/flexure joint, and the like to increase the range of motion (e.g., increase the degree of freedom). When moved, touch pad  34  is configured to actuate a circuit that generates one or more signals. The circuit generally includes one or more movement indicators such as switches, sensors, encoders, and the like. An example of a gimbaled track pad may be found in patent application Ser. No. 10/643,256, entitled, “MOVABLE TOUCH PAD WITH ADDED FUNCTIONALITY,” filed Aug. 18, 2003 (U.S. Patent Application Publication No. 2006/0026521), which is hereby incorporated by reference herein in its entirety for all purposes. 
     In the illustrated embodiment, track pad  34  takes the form of a depressible button that performs a “picking” action. That is, a portion of the entire track pad  34  acts like a single or multiple button such that one or more additional button functions may be implemented by pressing on track pad  34  rather than tapping on the track pad or using a separate button/separate zone. As shown in  FIGS.  12 A and  12 B , according to one embodiment of the invention, track pad  34  is capable of moving between an upright (or neutral) position ( FIG.  12 A ) and a depressed (or activate) position ( FIG.  12 B ) when a force from a finger  38 , palm, hand, or other object is applied to the track pad  34 . The force should not be so small as to allow for accidental activation of the button signal, but not so large as to cause user discomfort by requiring undue pressure. Track pad  34  is typically biased in the upright position as for example through a flexure hinge, a spring member, or magnets. Track pad  34  moves to the activate position when the bias is overcome by an object pressing on track pad  34 . As shown in  FIG.  12 C , the track pad  34  may be pivoted at one end such that the activate position is slightly inclined with respect to the neutral position. When the finger (or other object) is removed from track pad  34 , the biasing member urges it back towards the neutral position. A shim or other structure (not shown) may prevent track pad  34  from overshooting the neutral position as it returns. For example, a portion of frame  32  may extend outwardly above a portion of track pad  34  so as to stop track pad  34  at the neutral position. In this way, the track pad surface can be kept flush with frame  32  if desired. For example, in laptop computers or handheld media devices, it may be desirable to have the track pad flush with the housing of the computer or device. 
     As shown in  FIG.  12 A , in the upright/neutral position, track pad  34  generates tracking signals when an object such as a user&#39;s finger is moved over the top surface of the touch pad in the x, y plane. Although  FIG.  12 A  depicts the neutral position as being upright, the neutral position may be situated at any orientation. As shown in  FIG.  12 B , in the depressed position (z direction), track pad  34  generates one or more button signals. The button signals may be used for various functionalities including but not limited to making selections or issuing commands associated with operating an electronic device. By way of example, in the case of a music player, the button functions may be associated with opening a menu, playing a song, fast forwarding a song, seeking through a menu and the like. In the case of a laptop computer, the button functions can be associated with opening a menu, selecting text, selecting an icon, and the like. As shown in  FIG.  12 D , input device  30  may be arranged to provide both the tracking signals and the button signal at the same time, i.e., simultaneously depressing the touch pad  34  in the z direction while moving tangentially along the track surface (i.e., in the x, y directions). In other cases, input device  30  may be arranged to only provide a button signal when touch pad  34  is depressed and a tracking signal when the touch pad  34  is upright. 
     To elaborate, track pad  34  is configured to actuate one or more movement indicators, which are capable of generating the button signal when track pad  34  is moved to the activate position. The movement indicators are typically located within frame  32  and may be coupled to track pad  34  and/or frame  32 . The movement indicators may be any combination of switches and sensors. Switches are generally configured to provide pulsed or binary data such as activate (on) or deactivate (off). By way of example, an underside portion of track pad  34  may be configured to contact or engage (and thus activate) a switch when the user presses on track pad  34 . The sensors, on the other hand, are generally configured to provide continuous or analog data. By way of example, the sensor may be configured to measure the position or the amount of tilt of touch pad  34  relative to the frame when a user presses on the track pad  34 . Any suitable mechanical, electrical and/or optical switch or sensor may be used. For example, tact switches, force sensitive resistors, pressure sensors, proximity sensors and the like may be used. 
     Track pads  10  and  30  shown in  FIGS.  10 - 12    may, in some embodiments, be multi-touch trackpads. Multi-touch consists of a touch surface (screen, table, wall, etc.) or touchpad, as well as software that recognizes multiple simultaneous touch points, as opposed to the standard touchscreen (e.g., computer touchpad, ATM), which recognizes only one touch point. This effect is achieved through a variety of means, including but not limited to capacitive sensing, resistive sensing, surface acoustic wave sensing, heat, finger pressure, high capture rate cameras, infrared light, optic capture, tuned electromagnetic induction, and shadow capture. An example of a multi-touch mobile phone is the iPhone produced by Apple Inc. of Cupertino, CA. An example of a multi-touch media device is the iPod Touch produced by Apple Inc. Examples of laptop computers having multi-touch track pads are the MacBook Air and MacBook Pro produced by Apple Inc. All of the input devices described herein may employ multi-touch technology in some embodiments; alternatively the input devices described herein may employ single touch track pads. 
       FIG.  13    is a simplified block diagram of a computing system  39 , in accordance with one embodiment of the present invention. The computing system generally includes an input device  40  operatively connected to a computing device  42 . By way of example, the input device  40  may generally correspond to the input device  30  shown in  FIGS.  11  and  12   , and the computing device  42  may correspond to a laptop computer, desktop computer, PDA, media player, mobile phone, smart phone, video game or the like. As shown, input device  40  includes a depressible track pad  44  and one or more movement indicators  46 . Track pad  44  is configured to generate tracking signals and movement indicator  46  is configured to generate a button signal when the track pad  44  is depressed. Although track pad  44  may be widely varied, in this embodiment, track pad  44  includes capacitance sensors  48  and a control system  50  for acquiring the position signals from sensors  48  and supplying the signals to computing device  42 . Control system  50  may include an application specific integrated circuit (ASIC) that is configured to monitor the signals from sensors  48 , to compute the location (Cartesian or angular), direction, speed and acceleration of the monitored signals and to report this information to a processor of computing device  42 . Movement indicator  46  may also be widely varied. In this embodiment, however, movement indicator  46  takes the form of a switch that generates a button signal when track pad  44  is depressed. Switch  46  may correspond to a mechanical, electrical or optical style switch. In one particular implementation, switch  46  is a mechanical style switch that includes a protruding actuator  52  that may be pushed by track pad  44  to generate the button signal. By way of example, the switch may be a tact switch or tactile dome. 
     Both track pad  44  and switch  46  are operatively coupled to computing device  42  through a communication interface  54 . The communication interface provides a connection point for direct or indirect connection between the input device and the electronic device. Communication interface  54  may be wired (wires, cables, connectors) or wireless (e.g., transmitter/receiver). 
     Computing device  42  generally includes a processor  55  (e.g., CPU or microprocessor) configured to execute instructions and to carry out operations associated with the computing device  42 . For example, using instructions retrieved for example from memory, the processor may control the reception and manipulation of input and output data between components of the computing device  42 . In most cases, processor  55  executes instruction under the control of an operating system or other software. Processor  55  can be a single-chip processor or can be implemented with multiple components. 
     Computing device  42  also includes an input/output (I/O) controller  56  that is operatively coupled to processor  55 . I/O controller  56  may be integrated with processor  55  or it may be a separate component, as shown. I/O controller  56  is generally configured to control interactions with one or more I/O devices that can be coupled to computing device  42 , for example, input device  40 . I/O controller  56  generally operates by exchanging data between computing device  42  and I/O devices that desire to communicate with computing device  42 . 
     Computing device  42  also includes a display controller  58  that is operatively coupled to processor  55 . Display controller  58  may be integrated with processor  55  or it may be a separate component, as shown. Display controller  58  is configured to process display commands to produce text and graphics on a display screen  60 . By way of example, display screen  60  may be a monochrome display, color graphics adapter (CGA) display, enhanced graphics adapter (EGA) display, variable-graphics-array (VGA) display, super VGA display, liquid crystal display (LCD) (e.g., active matrix, passive matrix and the like), cathode ray tube (CRT), plasma displays, backlit light-emitting diode (LED) LCD displays, or the like. 
     In one embodiment (not shown), track pad  44  can comprise a glass surface functioning not only as a touch-sensitive surface, but also as a display screen; in this case display screen  60  shown in  FIG.  13    would be integrated with the glass surface of the track pad  44 . This could be useful in computing devices (e.g., media players or mobile phones) having touch sensitive displays. An example of a media player having a touch sensitive display is the iPod Touch produced by Apple Inc. of Cupertino CA. An example of a mobile phone having a touch sensitive display is the iPhone produced by Apple Inc. of Cupertino CA. 
     In most cases, processor  55  together with an operating system operates to execute computer code and produce and use data. The computer code and data may reside within a program storage area  62  that is operatively coupled to processor  55 . Program storage area  62  generally provides a place to hold data that is being used by computing device  42 . By way of example, the program storage area may include Read-Only Memory (ROM), Random-Access Memory (RAM), hard disk drive and/or the like. The computer code and data could also reside on a removable program medium and loaded or installed onto the computing device when needed. In one embodiment, program storage area  62  is configured to store information for controlling how the tracking and button signals generated by input device  40  are used by computing device  42 . 
       FIG.  14    shows one embodiment of an input device, generally shown at  70 , comprising a track pad  72  connected to a frame  76 . Frame  76  may be a housing for a stand alone input device, or it may be a casing for another device which incorporates track pad  72 , for example a laptop computer, desktop computer, hand held media device, PDA, mobile phone, smart phone, etc. Track pad  72  includes various layers including an outer touch-sensitive track surface  74  for tracking finger movements. Track surface  74  may also provide a low friction cosmetic surface. In one embodiment, track pad  72  is based on capacitive sensing; therefore, it includes an electrode layer  80 , which, for example, may be implemented on a PCB. In the case of capacitive sensing, track surface  74  is a dielectric material. A stiffener  84  is located below electrode layer  80 . Stiffener  84  is shown in  FIG.  14    and  FIG.  15   , but in some embodiments may be omitted. Stiffener  84  may be used to compensate for the inherent flexibility of electrode layer  80 . Electrode layer  80  responds to finger movements along to track surface  74  by sending signals to sensor  82 . In the case of capacitive sensing, electrode layer  80  registers changes in capacitance based on finger movements and sensor  82  is a capacitive sensor. In this way, track pad  72  incorporates a touch sensor arrangement. Sensor  82  is shown disposed on the bottom of electrode layer  80 , but it may be located elsewhere in other embodiments. If, as in the illustrated embodiment, sensor  82  is located on a movable part of track pad  72 , the input device may incorporate a flexible electrical connection (not shown) capable of moving with the system. 
     A movement indicator  78  is disposed on the bottom of track pad  72 . Movement indicator  78  may be widely varied, however, in this embodiment it takes the form of a mechanical switch, which is typically disposed between the track pad  72  and the frame  76 . In other embodiments, movement indicator  78  may be a sensor, for example an electrical sensor. Movement indicator  78  may be attached to frame  76  or to track pad  72 . In the illustrated embodiment, movement indicator  78  is attached to the bottom side of electrode layer  80 . By way of example, if electrode layer  80  is located on a PCB, movement indicator  78  may be located on the bottom of the PCB. In another example, movement indicator  78  may tack the form of a tact switches and more particularly, may be an SMT dome switches (dome switch packaged for SMT). 
     Track pad  72  is shown in its neutral position in  FIG.  14   , where movement sensor  78  is not in contact with frame  76 . When a user applies a downward pressure to track surface  74 , track pad  72  may move downward causing movement sensor  78  to register this change in position. In the illustrated embodiment, movement sensor  78  (a tact switch) would contact either frame  76 , or in this case set screw  88 . Set screw  88  may be manually adjusted to alter the distance between the neutral and activate positions. In one embodiment (not shown), set screw  88  may directly abut movement sensor  78  in the neutral position, such that there is no slack or pre-travel in the system. A flexure hinge  86  connects track pad  72  with frame  76 . Flexure hinge  86  is a resilient material that flexes when a force is applied, but exerts a restoring force so as to urge track pad  72  back towards the neutral position. In one embodiment, flexure hinge  86  may be thin spring steel. 
     As shown in  FIG.  15   , flexure hinge  86  will flex when a user pushes down on track surface  74 . Flexure  86  also urges track pad  72  towards its neutral position, which in the illustrated embodiment shown in  FIG.  14    is horizontal. In this way, a user can press down virtually anywhere on track surface  74  and cause a “pick,” meaning that movement indicator  78  will register this depression. This is in contrast to prior track pads which incorporate separate track zones and pick zones. Being able to pick anywhere on track surface  74  will provide the user with a more intuitive and pleasurable interface. For example, a user may be able to generate tracking and button signals with a single finger without ever having to remove the finger from track surface  74 . In contrast, a user operating a track pad with separate track and pick zones may, for example, use a right hand for tracking and a left hand for picking, or a forefinger for tracking and thumb picking. 
     A shoulder  90 , which may be an extension of frame  76  or a discrete member, blocks track pad  72  from travelling past its neutral position by contacting a part of track pad  72 , for example stiffener  84 . In this way, track surface  74  may be kept substantially flush with a top surface of frame  76 . There may be a shock absorber or upstop (not shown) incorporated in conjunction with shoulder  90  to cushion contacts between track pad  72  and shoulder  90 . 
     As should be appreciated, the pick generated by pressing on track surface  74  may include selecting an item on the screen, opening a file or document, executing instructions, starting a program, viewing a menu, and/or the like. The button functions may also include functions that make it easier to navigate through the electronic system, as for example, zoom, scroll, open different menus, home the input pointer, perform keyboard related actions such as enter, delete, insert, page up/down, and the like. 
     Flexure hinge  86  allows for a movable track pad in the minimum vertical space possible. Minimum vertical space is achieved because flexure hinge  86  is thin and is generally situated parallel to a bottom layer of track pad  72 ; consequently, flexure hinge  86  does not appreciably add to the thickness of track pad  72 . Therefore, this arrangement is feasible for use in ultrathin laptop computers. In such ultrathin laptop computer applications, vertical space is extremely limited. In the past, the size of electrical components was often the limiting feature as to how small electrical devices could be made. Today, electrical components are increasingly miniaturized, meaning that mechanical components (e.g., movable track pads) may now be the critical size-limiting components. With this understanding, it is easy to appreciate why linear-actuation (e.g., supporting a movable track pad by coil springs or the like) is not ideal in some applications. Furthermore, using springs may add unnecessary complexity (increased part count, higher cost, higher failure rates, etc. . . . ) to the manufacturing process. Another disadvantage of springs is that in some embodiments springs may mask or compromise the tactile switch force profile. In contrast, flexure  86  can deliver a substantially consistent feel across the track surface  74 , and give the user a more faithful representation of the tactile switch force profile. 
     Referring now to  FIG.  15   , according to one embodiment of the present invention, when a user presses on track surface  74  of track pad  72 , track pad  72  pivots downwardly activates switch  78  disposed underneath. When activated, switch  78  generates button signals that may be used by an electronic device connected to input device  70 . Flexure  86  can constrain track pad  72  to move substantially about only one axis. This can be accomplished by, for example, using multiple flexures arranged along an axis on one side of track pad  72 , such as the rear side. Furthermore, if track pad  72  is made stiff (for example, by inclusion of stiffener  84  if necessary), a leveling architecture is achieved. In other words, flexure hinge  86  urges track pad  72  towards its neutral position and also permits movement about substantially only one axis, i.e., the axis along which flexure hinge  86  is connected to frame  76 . 
     Although embodiments of this invention have been fully described with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of embodiments of this invention as defined by the appended claims.

Metadata:
Filing Date: 20220817
Publication Date: 20240130
Grant Date: 20240130
Priority Date: 20080104
Inventors: WESTERMAN, WAYNE CARL
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F3/04886", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0418", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0488", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04186", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04883", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0416", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04104", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04106", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04808", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0418", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/04186", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0416", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/04886", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/017", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/041", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0488", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04883", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04886", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04809", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04808", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04106", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04101", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04104", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04883", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04886", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0488", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0418", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/04883", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0416", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/04186", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0488", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04104", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04106", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F2203/04808", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 40343772