PATENT DOCUMENT

Publication Number: US-9639179-B2
Application Number: US-201213620044-A
Country: US
Kind Code: B2

Title: Force-sensitive input device

Abstract:
An input device for computing devices that include touch screens. The input device includes an outer housing having an inner surface and an inner shaft. The inner shaft is at least partially received within the outer housing. A nib is operatively coupled to the inner shaft. Providing a first force to the nib causes the inner shaft to contact the inner surface of the outer housing at a first contact point along the outer housing, and providing a second force to the nib causes the inner shaft to contact the inner surface of the outer housing at a second contact point along the outer housing.

Claims:
What is claimed is: 
     
       1. An input device for computing devices comprising:
 an outer housing having an inner surface that provides a variable resistance; 
 an inner shaft at least partially received within the outer housing; 
 a nib operatively coupled to the inner shaft; wherein 
 providing a first force to the nib causes the inner shaft to contact the inner surface at a first contact point along the outer housing; 
 providing a second force to the nib causes the inner shaft to contact the inner surface of the outer housing at a second contact point along the outer housing, wherein the first and second contact points are at different locations along a length of the outer housing, and wherein the input device generates a first electrical signal in response to the inner shaft contacting the inner surface of the outer housing at the first contact point and generates a second electrical signal in response to the inner shaft contacting the inner surface of the outer housing at the second contact point, and 
 a circuit that measures the first and second forces provided to the nib by measuring capacitance discharges across the variable resistance of the inner surface when the inner shaft contacts the inner surface at the first and second contact points. 
 
     
     
       2. The input device of  claim 1 , wherein the inner shaft comprises an outer surface, and the outer surface of the inner shaft contacts the inner surface of the outer housing responsive to the first and second forces. 
     
     
       3. The input device of  claim 1 , wherein the outer surface of the inner shaft selectively forms an electrical connection at the first and second contact points of the outer housing. 
     
     
       4. The input device of  claim 1 , wherein the first force causes the inner shaft to bend at a first bend point along the inner shaft, the first bend point being coupled to the first contact point responsive to the first force. 
     
     
       5. The input device of  claim 1 , wherein the inner shaft comprises a conductive element, and wherein the input device further comprises a substantially constant voltage source coupled to a first portion of the inner surface. 
     
     
       6. The input device of  claim 5 , wherein a second portion of the inner surface is coupled to a reference voltage node. 
     
     
       7. The input device of  claim 1 , wherein the inner surface is a resistive element that provides the variable resistance. 
     
     
       8. The input device of  claim 7 , wherein the variable resistance of the inner surface increases along the length of the outer housing. 
     
     
       9. An apparatus comprising:
 an inner shaft having first and second opposing ends and including an electrically conductive portion at the first end, wherein the inner shaft extends between the first and second opposing ends along a longitudinal axis; 
 a nib operatively coupled to the second end of the inner shaft and configured to bias the inner shaft in a biasing direction within a rigid housing; and 
 a plurality of parallel conductive disks attached to the inner shaft along the longitudinal axis between the electrically conductive portion and the nib, wherein each of the conductive disks makes electrical contact with an inner surface of the rigid housing at a respective location of the rigid housing along the longitudinal axis, wherein the biasing direction is orthogonal to the longitudinal axis. 
 
     
     
       10. The apparatus of  claim 9 , wherein at least a portion of the inner shaft is flexible. 
     
     
       11. The apparatus of  claim 10 , wherein the nib is configured to bias the flexible inner shaft responsive to a first force such that a first one of the plurality of parallel conductive disks makes electrical contact with the inner surface at a first location along the longitudinal axis, and wherein the nib is further configured to bias the flexible inner shaft responsive to a second force greater than the first force such that a second one of the plurality of parallel conductive disks makes electrical contact with the inner surface at a second location along the longitudinal axis. 
     
     
       12. The apparatus of  claim 9 , wherein the inner shaft comprises an outer surface, and the outer surface comprises the electrically conductive portion. 
     
     
       13. The apparatus of  claim 9 , wherein the inner shaft comprises a depth plunger. 
     
     
       14. The apparatus of  claim 9 , wherein a plurality of resistances are coupled between the plurality of parallel conductive disks. 
     
     
       15. A stylus for providing an input to a touch interface of a computing device, comprising: an elongated body; a nib operably coupled to the elongated body; and an inner shaft operably coupled to the nib and at least partially received within the elongated body, wherein the inner shaft comprises an insulator and a conductive disc that contacts an inner surface of the elongated body; wherein
 movement of the nib causes a portion of the inner shaft interposed between the nib and the insulator to bend towards and make direct electrical contact with the inner surface of the elongated body and causes the conductive disc to slide along and make direct electrical contact with the inner surface of the elongated body. 
 
     
     
       16. The stylus of  claim 15 , wherein the stylus is configured to provide a signal indicative of a location of the direct electrical contact between the portion of the inner shaft and inner surface of the elongated body. 
     
     
       17. The stylus of  claim 15 , wherein the movement of the nib is radial movement relative to the elongated body. 
     
     
       18. The stylus of  claim 15 , wherein the nib is electrically coupled to an outer surface of the elongated body and the stylus is configured for use with a capacitive touch interface. 
     
     
       19. A method for operating an input device for a computing device, comprising:
 determining first and second contact positions at which an inner shaft makes direct electrical contact with an outer housing having an inner surface that provides a variable resistance, the first and second contact positions varying responsive to a force provided to the nib such that the inner shaft makes direct electrical contact with the inner surface at the first contact position in response to a first force and the inner shaft makes direct electrical contact with the inner surface at the second contact position in response to a second force that is different than the first force; 
 with a circuit in the input device, measuring the first and second forces provided to the nib by measuring capacitance discharges across the variable resistance of the inner surface when the inner shaft contacts the inner surface at the first and second contact positions; and 
 providing a first output signal responsive to the first contact position and providing a second output signal responsive to the second contact position. 
 
     
     
       20. The method of  claim 19 , wherein the first output signal provided responsive to the first contact position increases in magnitude as the force applied to the nib increases. 
     
     
       21. The method of  claim 19 , further comprising transmitting the first output signal to the computing device. 
     
     
       22. The method of  claim 19 , wherein the first contact position of the inner shaft with the inner surface is determined by voltage dividing a voltage applied to the inner surface through a wiper, the wiper comprising the inner shaft. 
     
     
       23. The method of  claim 19 , further comprising determining an orientation of the input device relative to the computing device and transmitting the orientation to the computing device.

Description:
TECHNICAL FIELD 
     The present invention relates generally to computing devices, and more specifically, to input devices for computing devices. 
     BACKGROUND 
     Many types of input devices may be used to provide input to computing devices, such as buttons or keys, mice, trackballs, joysticks, touch screens and the like. Touch screens, in particular, are becoming increasingly popular because of their ease and versatility of operation. Typically touch screens on interfaces can include a touch sensor panel, which may be a clear panel with a touch-sensitive surface, and a display device that can be positioned behind the panel so that the touch-sensitive surface substantially covers the viewable area of the display device. Touch screens allow a user to provide various types of input to the computing device by touching the touch sensor panel using a finger, stylus, or other object at a location dictated by a user interface being displayed by the display device. In general, touch screens can recognize a touch event and the position of the touch event on the touch sensor panel, and the computing system can then interpret the touch event in accordance with the display appearing at the time of the touch event, and thereafter can perform one or more actions based on the touch event. 
     Touch sensor panels can be formed from a matrix of row and column traces, with sensors or pixels present where the rows and columns cross over each other while being separated by a dielectric material. Each row can be driven by a stimulation signal, and touch locations can be identified through changes in the stimulation signal. Typically, a touch location is sensed based on an interference of the stimulation signal, such that a touch location may correspond to a location where the stimulation signal is the weakest. In some instances it may be desirable for a user to provide input to the touch screen with an input device other than the user&#39;s finger or fingers. Some input devices, such as styli, allow a user to use the input device as a pen or pencil and “write” on the touch screen. However, depending on the mode of operation of the touch sensor panels, the computing device may not be able to detect certain characteristics of the input stimulation provided by the user through the stylus. For example, in a capacitive-sensing touch screen, the touch sensor panels may not be able to detect how much force (e.g., pressure) is exerted by the user on the touch screen through the stylus and instead may only be able to detect the presence or absence of the stylus. The user may thus not be able to “write” on the touch screen with as much control as the user would be able to write on paper with a ballpoint pen or other non-electronic writing tool because, for example, the thickness of the lines drawn on a touch screen by the stylus will be uniform regardless of the force exerted by the user. 
     SUMMARY 
     One example of the present disclosure may take the form of an input device for computing devices. The input device includes an outer housing having an inner surface. The input device also includes an inner shaft, with the inner shaft at least partially received within the outer housing. The input device also includes a nib operatively coupled to the inner shaft. Providing a first force to the nib causes the inner shaft to contact the inner surface of the outer housing at a first contact point along the outer housing, and providing a second force to the nib causes the inner shaft to contact the inner surface of the outer housing at a second contact point along the outer housing. 
     Another example of the disclosure may take the form of an apparatus including an inner shaft with an electrically conductive portion. The apparatus also includes a nib operatively coupled to the inner shaft and configured to bias the inner shaft in a first biasing direction within a rigid housing such that the electrically conductive portion of the inner shaft contacts the rigid housing at a first location along a longitudinal axis of the rigid housing. 
     Another example of the present disclosure may take the form of a stylus for providing an input to a touch interface of a computing device. The stylus includes an elongated body and a nib operably coupled to the elongated body. The stylus also includes an inner shaft operably coupled to the nib and at least partially received within the elongated body. Movement of the nib causes a portion of the inner shaft to bend towards the elongated body. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a system including a computing device and an input device communicating therewith. 
         FIG. 2  is a simplified, partial cross-section view of a touch screen of a computing device taken along line  2 - 2  in  FIG. 1 . 
         FIG. 3  is a block diagram of a simplified, sample touch-sensing system of the computing device of  FIG. 1 . 
         FIG. 4  is a perspective view of an input device having a nib. 
         FIG. 5  is a simplified block diagram of the input device of  FIG. 4 . 
         FIG. 6A  is a partial cross-section view of a first embodiment of the input device of  FIG. 4  with a first force provided to the nib. 
         FIG. 6B  is a partial cross-section view of a first embodiment of the input device of  FIG. 4  with a second force provided to the nib. 
         FIG. 7A  is a partial cross-section view of a second embodiment of the input device of  FIG. 4  with the first force provided to the nib. 
         FIG. 7B  is a partial cross-section view of a second embodiment of the input device of  FIG. 4  with the second force provided to the nib. 
         FIG. 8A  is a top plan view of a sample computing device receiving an input from the input device with the first force provided to the nib. 
         FIG. 8B  is a top plan view of the computing device receiving an input from the input device with the second force provided to the nib. 
         FIG. 9A  is a partial cross-section view of the first embodiment of the input device of  FIG. 4  taken along line  9 - 9  in  FIG. 4 , with the first force provided to the nib. 
         FIG. 9B  is a partial cross-section view of the second embodiment of the input device of  FIG. 4  taken along line  9 - 9  in  FIG. 4 , with the first force provided to the nib. 
         FIG. 9C  is a partial cross-section view of a third embodiment of the input device of  FIG. 4  taken along line  9 - 9  in  FIG. 4 , with the first force provided to the nib. 
         FIG. 9D  is a partial cross-section view of a fourth embodiment of the input device of  FIG. 4  taken along line  9 - 9  in  FIG. 4 , with the first force provided to the nib. 
     
    
    
     SPECIFICATION 
     Overview 
     In some embodiments herein, an input device having a nib is disclosed. In one embodiment, the input device may take the form of a stylus that may be used to communicate with a display, such as a touch screen or touch interface, of a computing device. The stylus may include a nib or tip, and the stylus may sense various forces exerted on the nib when, for example a user “writes” with the stylus on a tablet computing device. In one embodiment, the stylus includes an outer housing and an inner shaft. The inner shaft is received within the outer housing and is coupled to the nib such that movement on the nib induces movement on the inner shaft. For example, a force exerted on the nib may cause the inner shaft to bend and/or to retract within the outer housing. The bending or sliding of the inner shaft may result in one or more contact points between the inner shaft and the outer housing. Electrical currents and voltages may be manipulated to measure a position of the contact point or points of the inner shaft with the outer housing in order to help determine the magnitude, the direction, or other characteristics of a force provided to the nib, to the stylus, and so forth. 
     As the point or points of contact vary, the stylus provides varying input signals to the computing device responsive to the changes in the contact points. As a result, a user may be able to change an input to the computing device (e.g., make a line thicker) by merely changing the force applied to the nib of the stylus, similar to what can be done with a ball-point pen or pencil on paper. 
     Turning now to the figures, a communication system including a computing device and an input device will be discussed in more detail.  FIG. 1  is a perspective view of an input system  100  including a stylus  104  in communication with a computing device  102  through a touch screen  106 . The computing device  102  may be substantially any type of electronic device and may include a touch interface or screen  106 , which may be a capacitive input mechanism. For example, the computing device  102  may be a laptop computing device, a tablet computing device, a smartphone, a digital music player, portable gaming station, or the like. Although not shown, the computing device  102  may include one or more components of a typical electronic or computing device, such as one or more processing components, to provide control or provide other functions for the device  102 . Some illustrative components for operating and communicating with the touch screen  106  are discussed in more detail below with respect to  FIGS. 4 and 5 . 
     The computing device  102  may include the touch screen  106 , an enclosure  110 , and/or one or more input buttons  108 . The enclosure  110  encloses one or more components of the computing device  102 , as well as may surround and/or secure a portion of the touch screen  106  to the computing device  102 . The one or more input buttons  108  may provide input functions to the computing device  102 . For example, the input buttons  108  may adjust a volume for the computing device  102 , turn the computing device  102  on or off, or may provide other inputs for the computing device  102 . Further, the computing device  100  may also include one or more receiving ports  112 . The receiving ports  112  may receive one or more plugs or connectors, such as, but not limited to, a universal serial bus (USB) cable, a tip ring sleeve connector, a proprietary connector, a FireWire connector, or the like. 
     The Touch Screen 
     The touch screen  106  may include one or more sensors in order to detect one or more input signals based on user touches or inputs from a stylus  104  or other input device. Additionally, the touch screen  106  may include a display screen to provide a graphical user interface, and other video and/or image output for the computing device  102 .  FIG. 2  is a cross-section view of the touch screen  106  taken along line  2 - 2  in  FIG. 1 . The touch screen  106  is configured to receive inputs from an object (e.g., location information based on a user&#39;s finger or input device), or to sense a location of an object through a change in capacitance at a point touched by an object (or nearly touched by an object), and to send this information to a processor. The touch screen  106  may report touches to one or more processors and the processor interprets the touches in accordance with its programming. For example, the processor may initiate a task in accordance with a particular touch. The touch screen  106  may include a display screen  112  and a sensor panel  114  positioned at least partially over the display screen  112 . The display screen  112  is configured to display one or more output images and/or videos for the computing device  102 . The display screen  112  may be substantially any type of display mechanism, such as a liquid crystal display (LCD), organic light-emitting diode display, light-emitting diode display, plasma display, or the like. In instances where the display screen  112  is an LCD display, the display screen  112  may include (not shown) various layers such a fluorescent panel, one or more polarizing filters, a layer of liquid crystal cells, a color filter, a pixel array, or the like. It should be noted that  FIG. 2  is not drawn to scale and is a sample, partial schematic view of the touch screen. In some embodiments, the touch screen and pixels of the display may be co-planar, while in other embodiments the touch screen may be located above or below the display. 
     The sensor panel  114  may include an electrode layer  116  operably connected to a sensor glass  118  or other type of support structure. The electrodes  116  may be connected to one or both sides of the sensor glass  118 . As one example, the electrodes  116  may be positioned on a first side of the sensor glass  118 , and the other side of the glass may be coated to form a ground shield. As another example, the sensor glass  118  may be formed of multiple layers of polyethylene terephthalate (PET), with each layer including electrodes  116  operably connected to one side of the layer, and then each of the layers may be stacked to form rows, columns, and/or shield layers. 
     With continued reference to  FIG. 2 , the sensor glass  118  may form a portion of the display screen  112  or may be separate therefrom. The sensor glass  118  may be a relatively clear element that may protect the display screen  112  from forces that may be exerted on the sensor panel  114  by a user or input device. In some embodiments, the sensor glass  118  may be a clear glass panel that may allow the display screen  112  to be viewable therethrough. The electrode layer  116  may include one or more electrodes which may be deposited on the sensor glass  118 . For example, the electrode layer  116  may include transparent conductive materials and pattern techniques such as ITO and printing. It should be noted that the electrode layer  116  may include a plurality of electrodes separated by gaps, where the electrodes are interconnected by one or more traces or other electrical elements. 
     The electrode layer  116  may include one or two layers of electrodes which may be spaced apart across the layer  116 . The electrodes, discussed in more detail with respect to  FIG. 3 , may define one or more nodes  144  that act as capacitive coupling sensors to detect touches on the touch screen  106 . The number and configuration of the nodes  144  may be varied, depending on the desired sensitivity of the touch screen  106 . 
     The touch screen  106  may also include a cover surface  120  disposed over the electrode layer  116 . Thus, the electrode layer  116  may be substantially sandwiched between the cover surface  120  and the sensor glass  118 . The cover surface  120  protects the other layers of the touch screen  106 , while also acting to insulate the electrode layer  116  from external elements (such as fingers or input devices that may contact the cover surface  120 ). The cover surface  120  may generally be formed from substantially any suitable clear material, such as glass or plastic. Additionally, typically the cover surface  120  should be sufficiently thin to allow for sufficient electrode coupling between the electrode layer  116  and any external input objects (e.g., fingers, input devices). For example, the cover surface  120  may have a thickness ranging between 0.3 to 2 mm. 
     It should be noted that, in some embodiments, the touch screen  106  may be substantially any type of touch interface. For example, the touch interface may not be see-through and/or may not correspond to a display screen. In these instances, a particular surface or group of surfaces may be configured to receive touch inputs that may or may not correspond to a separately displayed user interface, icons, or the like. 
     Operation of the touch screen  106  will now be discussed in more detail.  FIG. 3  is an illustrative block diagram of the computing device  102  and touch screen  106 . The sensor panel  114  of the touch screen  106  may be configured to detect touches on the surface of the touch screen  106  by detecting changes in capacitance at a sensing node  144 . With reference to  FIG. 3 , a sensing node  144  formed by one or more electrodes (explained below) may form a first electrically conductive member and an object, such as a finger of the user or a stylus, may form a second electrically conductive member. The sensor panel  114  of the touch screen  106  may be configured in a self capacitance arrangement or in a mutual capacitance arrangement. 
     In the self capacitance arrangement, the electrode layer  116  may include a single layer of a plurality of electrodes spaced in a grid or other coordinate system (e.g., Polar) where each electrode may form a node  144 . The sensing circuit  150  monitors changes that may occur at each node  144 , which typically occurs at a node  144  when a user places an object (e.g., finger or nib  122  of the stylus  104 ) in close proximity to the electrode. 
     With continued reference to  FIG. 3 , in a mutual capacitance system, the electrode layer  116  may include electrodes separated into two layers forming drive lines  142  and sense lines  140 . The drive lines  142  may be formed on a first layer of the electrode layer  116  and the sense lines  140  may be formed on a second layer of the electrode layer  116 . The nodes  144  for the sensor panel  114  may be defined at locations of the electrode layer  116  where the drive lines  142  may cross the sense lines  140  (although in different layers). The sense lines  140  may intersect the drive lines  142  in a variety of manners. For example, in one embodiment, the sense lines  140  are perpendicular to the drive lines  142 , thus forming nodes  144  with x and y coordinates. However, other coordinate systems can also be used, and the coordinates of the nodes  144  may be differently defined. 
     A drive controller  146  is connected to each of the drive lines  142 . The drive controller  146  provides a stimulation signal (e.g., voltage) to the drive lines  142 . The sensing circuit  150  is connected to each of the sense lines  140  and the sensing circuit  150  acts to detect changes at the nodes  144 . During operation, the stimulation signal is applied to the drive lines  142  and due to the capacitive coupling between the drive lines  142  and sensing rows  140 , a current is carried through to the sense lines  140  at each of the nodes  144 . The sensing circuit  150  then monitors changes at each of the nodes  144 . As with the self-capacitance arrangement, changes in capacitance at the nodes  144  typically occurs when a user places an object such as a finger in close proximity to the node  144  as the object alters the capacitance at the node  144 . 
     In a specific embodiment, each drive line  142  may be driven separately or in groups, such that the drive controller  146  may selectively apply the stimulation signal to drive lines  142 . Each drive line  142  or bank of drive lines may be driven sequentially until the entire set of drive lines  142  has been driven. Although the drive lines  142  are driven individually or in groups, the sensing circuit  150  may sense changes along all of the sense lines  140  in parallel. In this manner, the coordinates of a touch node  144  may be more easily determined. 
     In some embodiments, the drive rows  142  and sensing columns  140  may be co-planar, such that they are not vertically separated. The drive rows  142  may be broken into a series of separate drive elements, each of which is connected to adjacent drive elements by a bus or metal trace. Vias may extend from each drive element to the metal trace, thereby forming a continuous path for an electrical signal. 
     In either the self-capacitance or mutual capacitance arrangements discussed above, the sensing circuit  150  can detect changes at each node  144 . This may allow the sensing circuit  150  to determine when and where a user or the stylus  104  has touched various surfaces of the touch screen  106  with one or more objects. The sensing circuit  150  may include one more sensors for each of the sense lines  140  and may then communicate data to a processor  148 . In one example, the sensing circuit  150  may convert the analog signals to digital data and then transmit the digital data to the processor  148 . In other examples, the sensing circuit  150  may transmit the analog signals to the processor  148 , which may then convert the data to a digital form. Further, it should be noted that the sensing circuit  150  may include individual sensors for each sensing line  140  or a single sensor for all of the sense lines  140 . The sensing circuit  150  may report a location of the node  144 , as well as changes in capacitance at the node  144 . 
     With reference to  FIG. 3 , the sensing circuit  150  may also include a multiplexer  154 . The multiplexer  154  may be configured to perform time multiplexing for the sense lines  140 . For example, the sensing circuit  150  may receive signals from each of the nodes  144  along the sense lines  140  at approximately the same time, the multiplexer  154  stores the incoming signals, and then may release the signals sequentially to the processor  148  one at a time. 
     The sensing circuit  150  may also include a converter  156 . The converter  156  transforms signals from a first signal to a second signal. For example, the converter  156  may transform analog signals to digital signals. As one example, the converter  156  may receive voltage signals from the sense lines  140  which may vary based on the amount of capacitive coupling at each of the nodes  144  and may transform those voltage signals into digital signals. 
     In some instances, the capacitance at each node  144  of the touch screen  106 , and signals sensed by the electrode layer  116  may be responsive in part to the physical geometry of the touch screen  106  and the object (e.g., a hand or a stylus  104 ) communicating with the touch screen  106 . The larger an object is, the larger the differences in capacitance that may be detected upon movement of the object; so increasing the size of the object may increase the touch screen&#39;s ability to detect a touch signal by that object. However, the touch screen  106  may not be able to detect changes in force (e.g., pressure) applied to the touch screen through the nib of a stylus because regardless of the force applied, the nib may have a substantially constant size detectable by the touch screen  106 . 
     The Input Device 
     Turning now to  FIG. 4 , the stylus  104  will be discussed in more detail.  FIG. 4  is a perspective view of the stylus  104 , showing a nib  122 . The stylus  104  may include an elongated body defined by an outer housing  170  that may at least partially enclose the nib  122 , as well as one or more other components of the stylus  104 , such as an inner shaft  180  (described in more detail below and shown in  FIGS. 6A-7B , among others). The outer housing  170  may be generally cylindrically shaped, and may taper towards one end  166  of the stylus  104  near the nib  122  in some embodiments as shown in  FIG. 4 . 
     The nib  122  may extend through a nib aperture  164  defined on a first end  166  of the stylus  104 . The nib  122  may be a generally flexible material that may deform upon force/pressure and resiliently return to its original shape. The nib  122  may be made at least partially of, or covered in, metals such as aluminum, brass or steel, as well as conductive rubber, plastic or other materials doped with conductive particles. In one embodiment the nib  122  may be Mylar, which may by sufficiently conductive to interact with a capacitive touch screen, but may also be flexible. In other embodiments, the nib may be made of, or covered with, non-conductive material so that the stylus  104  can be used with a non-capacitive sensing touch screen  106 , such as a resistive sensing touch screen. In general, the nib  122  may have any suitable shape, such as a round shape, a cone shape, a chisel shape, a fine point shape, and so forth. 
     The nib  122  may be coupled to the outer housing  170  of the stylus  104  and/or to the inner shaft  180  (described below) of the stylus  104  by a coupling device  168 , one example of which is shown in  FIG. 6A . In other embodiments, the nib  122  may be decoupled from the outer housing  170  and/or the inner shaft  180 . In one example, the nib  122  may be electrically coupled to the outer housing  170  such that charge is shared between the outer surface of the outer housing  170  and the nib  122 . Such sharing may facilitate use of the stylus  104  on a capacitive touch screen  106 . Also, the nib  122  may be coupled to other components of the stylus  104 , such as the inner shaft  180 . In some embodiments, the nib  122  is electrically coupled to the outer surface of the outer housing  170  such that charge is shared therebetween, and mechanically coupled to the inner shaft  180  so that movement of the nib  122  induces movement of the inner shaft  180  (including axial and/or radial movement of the inner shaft  180  relative to the outer housing  170 ). The nib  122  may be electrically isolated from the inner shaft  180  in some embodiments, including those where the inner shaft  180  comprises the nib  122  (e.g., an insulator may separate the nib  122  from the core of the inner shaft  180 ). The coupling device  168  may be a gimbal-type structure, a ball-point pen coupling structure, or any other suitable coupling structure. At least some of the coupling device may be elastic to allow movement and bending of the various parts of the stylus  104  (e.g., the inner shaft  180 ). 
     The nib  122  may be configured to be slid, traced or otherwise moved along the surface of the touch screen  106 , and interact therewith. For example, in embodiments where the nib  122  includes a conductive material, the nib  122  may interact with a capacitive sensing touch screen  106  and specifically one or more electrode layers to provide input to the computing device  102 . In some embodiments, the nib  122  may be configured to vary an electrical parameter, such as the capacitance at one or more of the nodes  144  of the touch screen  106 , which may be converted and provided as an input to the computing device  102 . For example, as the nib  122  contacts the surface of the touch screen  106 , the touch screen  106  may sense that contact. As the nib  122  interacts with the touch screen  106 , one or more nodes  144  may sense the presence of the stylus  104 . This may allow the touch screen  106  to be able to detect the presence of the nib  122 . The nib  122  may be coupled to the outer housing  170  of the stylus  104  in order to couple capacitance from a user&#39;s hand to the nib  122  and vice versa. 
     With reference now to the simplified block diagram in  FIG. 5 , the stylus  104  may also include one or more control and/or internal components. The stylus  104  may include a power source  188 , a processor  190 , an input/output interface  192 , and/or one or more sensors  194 . In some embodiments, the stylus  104  may also include a pre-processor circuit  198 . The electrical components of the stylus  104  may be in communication through one or more buses  196 . The power source  188  may provide power to one or more components of the stylus  104 . The power source  168  may be a portable power source, such as a battery, or may be a wired power source, such as a communication cord that may be configured to transfer power to the stylus  104  from an external component. Alternatively, the power source may derive power wirelessly from an external component. 
     The processor  190  may control select functions of the stylus  104 . In some embodiments, the processor  190  may determine one or more input signals that are to be transmitted to the touch screen  106  and/or computing device  102 , and in these instances, the processor  190  may control the signal transmission from the stylus  104 . 
     The stylus  104  may include an input/output (I/O) interface  192 . The I/O interface  192  may receive and/or transmit one or more signals to and from the stylus  104 . For example, the I/O interface  192  may receive and/or transmit one or more radio signals (e.g., Bluetooth, WiFi, Zigbee, near field communications, etc.) from and/or to the computing device  102 . One example of a signal that the stylus  104  may receive is an “active” signal provided by the computing device  102  when the touch screen  106  is in active use (e.g., a user is viewing content on, or actively controlled the computing device  102  through the touch screen  106 ). Upon receiving the active signal, the stylus  104  may enter an “active” state and may, for example, sample measurements (described below with reference to  FIGS. 9A through 9D ) with increased frequency. One example of a signal that the stylus  104  may transmit to the computing device  102  is a “force” signal that is indicative of a force applied to the nib  122  of the stylus  104 . 
     With continued reference to  FIG. 5 , the stylus  104  may also include one more sensors  194 , which may be powered in some embodiments at least in part by the power source  188 . In some instances the sensors  194  may be configured to detect one more stimuli of the nib  122 , the outer housing  170 , or other areas of the stylus  104  such as the inner shaft  180 . For example, the one more sensors  194  may include an accelerometer, a gyroscope, a force (e.g., pressure) sensor, and so on. In these instances, certain of the sensors  194 , such as an accelerometer and/or gyroscope, may be configured to detect changes in the orientation (e.g., angle) at which a user holds the stylus  104 . Other sensors, such as a force or pressure sensor, may be configured to detect a force with which the user presses the nib  122  against the touch screen  106  (several implementations of which are described below with reference to  FIGS. 9A through 90 ), and so on. The stylus  104  may be configured to change operation responsive to the output of one or more sensors  194 . For example, upon detecting that the stylus  104  is oriented in a particular manner (e.g., if an accelerometer determines that a particular surface is oriented “up”), the stylus  104  may provide a different functionality on the touch screen  106  (e.g., provide a wide line type of input to the computing device  102  as opposed to a narrower fine type of input to the computing device  102  when that same surface is oriented “down”). In some embodiments, the functionality may mirror the physical aspects of the stylus. For example, if the nib  122  is chisel-shaped similar to a highlighter, the angle at which it is held may vary the thickness of a line displayed on the display device in response to a sensed touch, accordingly. 
     The stylus  104  may optionally include a pre-processor circuit  198 . The pre-processor circuit  198  may filter or otherwise manipulate data sensed by the sensors  194  before providing the data to the processor  190 . For example, the pre-processor circuit  198  may include a diode configured to alternatingly provide a forward-biased signal and a reverse-biased signal to the processor circuit  190 , as described in more detail below with reference to  FIG. 9C . The pre-processor circuit  198  may include a capacitor in some embodiments, the capacitor configured to be charged and discharged at a rate determined responsive to the sensors  194 . 
     With reference to  FIGS. 6A and 6B , which are partial cross-section views of a first embodiment of a stylus  104 , and also with reference to  FIGS. 7A and 7B , which are partial cross-section views of a second embodiment of a stylus  104 , the structure and operation of several embodiments of a stylus  104  will now be described. 
     As mentioned above, the stylus  104  may include an inner shaft  180 . The inner shaft  180  may include an outer surface  181 , which, as described below with reference to  FIGS. 9A through 9D , may be coated with a conductive and/or a resistive material. In some embodiments, the shaft  180  itself may be at least partially composed of a conductive and/or a resistive material. In some but not all embodiments, the shaft may be somewhat elastic—for example the Young&#39;s modulus of the inner shaft may be between 0.01 and 1 GPa. In other embodiments, however, the shaft may be rigid. 
     As illustrated in  FIGS. 6A through 7B , in some embodiments the shaft may generally be cylindrically shaped, and may have a top portion  182 , which may generally be in the form of a disk. The diameter of at least some portions of the inner shaft  180  may generally be smaller than the diameter of the outer housing; in one example, the diameter of the core of the shaft  180  may only be 20 to 30 percent as great as the diameter of the inner surface of the outer housing  170 . The top portion  182  of the shaft  180  may, however, have a diameter that is substantially the same as or slightly less than the diameter of the inner surface of the outer housing  170  such that an electrical connection can be made therebetween. It should be appreciated that the shaft  180  may have different cross-sections in alternative embodiments. The shaft  180  may be square, hexagonal, or the like in different embodiments. 
     In some embodiments (with reference to  FIG. 9B  for example), the diameter of the top portion  182  may be greater than the diameter of the inner surface of the outer housing  170  such that the top portion  182  is lodged in the outer housing  170 . 
     It should be noted that the figures are not necessarily drawn to scale. It should also be noted that other sizes, shapes, and configurations of an inner shaft  180  are contemplated. For example, the core of the inner shaft  180  may have a rectangular or triangular cross section in some embodiments. As another example, the inner shaft  180  may not have a top portion  180  in the form of a disk, but may have a different top portion, which may or may not be coupled to the outer housing  170 , or may not have a top portion at all. 
     The inner shaft  180  may be able to measure one or more types of force exerted on the nib  122  of the stylus  104 . For example, when a user of the stylus  104  causes the nib  122  to contact the touch screen  106 , the nib  122  may experience one or more forces F 1 , F 2  normal to the plane of the touch screen  106 . Depending on the angle at which the stylus  104  is held relative to the touch screen  106  and the force applied by the user, the forces may be different, for example a second force F 2  may be greater in magnitude than a first force F 1 . Depending on the composition and configuration of the inner shaft  180 , the forces F 1 , F 2  may induce one or more types of movement of the inner shaft  180 . It should also be appreciated that a restoring force may be exerted on the nib, for example by the gimbal or other connecting device  168 . This nib restoring force may bias the nib (and thus the inner shaft) back to a neutral position in which the shaft does not contact any portion of the outer housing&#39;s inner sidewall. 
     Likewise, an additional force may be exerted normal to the axis of the inner shaft  180  when the inner shaft contacts the sidewall of the outer housing. That is, the housing may exert a shaft restoring force normal to the axis of the inner shaft against the shaft. Likewise, the shaft may exert a force against the housing in the opposite direction; this force may be transmitted through the connecting device  168  from the nib  122 . For purposes of clarity, these additional forces are not illustrated although they may be taken into account when modeling and estimating force exerted on the nib, in accordance with embodiments described herein. 
     For example, with reference to  FIGS. 6A and 6B , the forces F 1 , F 2  on the nib  122  may bias the inner shaft axially in biasing directions D B1 , D B2  along the length of the stylus  104 . In general, a greater force F 2  may bias the inner shaft  180  further up in the outer housing such that a length L 2  from the top portion  182  to an end  167  of the stylus  104  is greater than the length L 1  from the top portion  182  to the end  167  of the stylus when a lesser force F 1  is provided to the nib  122 . In other words, the forces may cause the inner shaft  180  to slide within the outer housing  170 . With reference to  FIGS. 6A and 6B , if the top portion  182  of the inner shaft  180  has a diameter that is substantially the same as, or slightly smaller than the diameter of the inner surface of the outer housing  170 , the sliding of the inner shaft  180  within the outer housing  170  may cause the top portion  182  to contact the outer housing  170  at different contact points C 1 , C 2  along the height of the outer housing  170 . 
     As another example, with reference to  FIGS. 7A and 7B , the inner shaft  180  may bend in response to a force that a user causes to be exerted on the nib  122 . However, depending on the magnitude and direction of the force, the inner shaft  180  may bend differently. For example, a lesser force F 1  may cause the shaft to bend in a biasing direction D B1  near one end  167  of the outer housing  170 , whereas a greater force F 2  may cause the shaft to bend in a biasing direction D B2  further towards the other end  166  of the outer housing  170 . The biasing directions D B1 , D B2  may be the same in some examples, although the location of bending may be different. Specifically, with reference to  FIG. 7A , a first, lesser force F 1  may cause the inner shaft  180  to bend at one bend point B 1 , which may in turn cause the inner shaft  180  to contact the inner surface of the outer housing  170  at a first contact point C 1 . With reference to  FIG. 7B , a second force F 2  (greater than the first force F 1 ) may cause the inner shaft  180  to bend at a second bend point B 2 , which may in turn cause the inner shaft  180  to contact the inner surface of the outer housing  170  at a second contact point C 2 . The distance L 1  from contact point C 1  to the end  167  of the stylus  104  may be shorter than the distance L 2  from contact point C 2  to the end  167  of the stylus  104   
     In general, a force applied to the nib  122  may cause the inner shaft  180  to slide axially within the outer housing  170  (e.g.,  FIGS. 6A and 6B ) and/or may cause the inner shaft  180  to bend towards the outer housing  170  (e.g.,  FIGS. 7A and 7B ). In other words, a force may cause the inner shaft  180  to retract within the outer housing  170  and/or may cause the inner shaft  180  to pivot/hinge/rotate/etc. with respect to the outer housing  170  and/or about the coupling device  168 . As described in more detail below with reference to  FIGS. 9A through 9D , the contact points C 1 , C 2  of the inner shaft  180  with the outer housing may determine a measurement and/or signal provided by the stylus  104  regarding the force applied to the nib  122 . 
     Whether the inner shaft  180  slides axially within the outer housing  170  and/or whether the inner shaft  180  bends towards the outer housing  170  may depend on, for example, the structure of the inner shaft  180  and the coupling device  168 . For example, if the inner shaft  180  is rigid, it may not bend, but may slide axially. As another example, if the inner shaft  180  is at least partially flexible, it may bend, but not slide axially. In still another example, if the inner shaft  180  is at least partially flexible, it may both bend and slide axially within the outer housing  170 . As still another example, if the coupling device  168  is a gimbal or ball joint structure, the different forces on the nib  122  may cause the inner shaft  180  to bend, but not to slide axially. However, if the coupling device  168  is a biased gimbal, the inner shaft may both bend and slide axially within the outer housing  170 . In general, either one or both of the bending and sliding of the inner shaft  180  may be provided based on the structure of the stylus  104  and the connections between the various components of the stylus. 
     In some embodiments (not shown in  FIGS. 6A through 7B ), the inner shaft  180  may be coupled to the outer housing  170  by a biasing member, in order to restore (e.g., re-center, realign, etc.) the inner shaft  180  to a neutral or no-force position. For example, with reference to  FIGS. 6A and 6B , a spring may bias the inner shaft  180  towards the other end  166  of the stylus such that when no force is applied, or when a previously applied force is withdrawn, the inner shaft  180  is biased towards a resting position. Alternatively, or in addition to a biasing member, the coupling device  168  may help restore the inner shaft  180  to a neutral position. Furthermore, in some embodiments, such as those illustrated in  FIGS. 7A and 7B , the inner shaft  180  may be elastic and may at least in part restore itself to a resting position when no force is applied to the nib  122 . 
     In operation, and with reference to  FIGS. 8A and 8B , as the force provided to the nib  122  varies, the stylus  104  may provide varying input to the computing device  102 . For example, even though the capacitive input provided to the touch screen  106  might not change as between two forces F 1 , F 2 , the stylus  104  may sense a different contact point C 1 , C 2 , of the inner shaft  180  and may provide a signal indicative of the contact point position to the computing device  102  through, for example, near field communication, WiFi, etc., as mentioned above. 
       FIG. 8A  is a top plan view of the computing device  102  receiving an input from the stylus  104  with a first force provided to the nib  122 . With reference to  FIGS. 6A, 7A, and 8A , a relatively small force may be exerted on the nib  122 . As shown in  FIG. 8A , the stylus  104  may provide an input of a first line  184  and the computing device  102  may display that first line on the computing device  102 . The first line  184  may have a first width or thickness, which may be relatively narrow. However, as the force provided to the nib varies, the thickness of the line input to the computing device  102  may also vary. In some instances, as the force provided to the nib  122  varies, other characteristics of the input to the computing device  102  may vary—for example, an increased force may be input to the computing device  102  as a different color, or a different brush tip. Generally, the input characteristic may vary depending on the pressure applied to the nib  122 . 
       FIG. 8B  is a top plan view of the computing device  102  receiving an input from the stylus  104  with a second force provided to the nib  122 , with the first force being greater than the second force (e.g., more pressure is applied to the nib  122 ). With reference to  FIGS. 6B, 7B , and  8 B, as the user causes more force to be exerted on the nib  122  (e.g., by pressing the stylus  104  harder against the touch screen  106 ), the stylus  104  may provide an input of a second line  184  and the computing device  102  may display that second line  186  on the computing device  102 . The second line  186  may have a second width or thickness, which may be greater than the width or thickness of the first line  184 . 
     Although the output lines  184 ,  186  are discussed herein as having varying widths or thicknesses, in other embodiments, the output thickness may be the same, but the flexibility of the nib may provide an enhanced user experience, as the stylus may have a more realistic feel. Alternatively, the outputs based on the force on the nib  122  may be otherwise varied, such as varying the output color, an input command to the computing device  102 , and so on. For example, when a first, light force is exerted relative to the computing device  102 , the computing device  102  may perform a first action (e.g., draw something), whereas when a second, more intense force is exerted, the computing device  102  may perform a second, different action (e.g., erase something). 
     With reference now to  FIG. 9A  (and referring back to  FIGS. 6A, 6B ), one example of a stylus  104  will be described in more detail. As illustrated in  FIG. 9A , the outer housing  170  may include a plurality of layers and/or surfaces. For example, the outer housing  170  may include an outer surface  171 , which may be conductive (for example aluminum), and as described above may be coupled to the nib  122  such that capacitance is shared between the nib  122  and a user&#39;s hand that is in contact with the outer surface  171 . The outer housing  170  may also include an insulation layer  172 , that may insulate the outer surface  171  from the inner surface  173 , and vice versa. The inner surface  173  of the outer shaft  180  may also be conductive and/or resistive in some embodiments. 
     One or more of the inner surface  173  of the outer housing  170  and the outer surface  181  of the inner shaft  180  may be coated with or at least partially formed from an electrically conductive but resistive material (such as carbon, cermet, etc.), which may in essence form part of a potentiometer within the stylus  104 . The resistance of the material may vary (e.g., linearly, logarithmically, etc.) according to a contact distance relative to an electrical connection on the material. In some embodiments, a resistive material may be provided that is nearly the entire circumference of the inner surface  173  of the outer housing  170  or the outer surface  181  of the inner shaft  180 . In other embodiments, multiple strips (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, etc.) of resistive material may be provided, which may facilitate determining an orientation of the stylus  104  relative to gravity. 
     As just one example, if: the inner wall  173  of the outer housing  170  is coated with a resistive material whose contact resistance varies linearly along the length of the inner wall  173  (with respect to an electrical connection at one end of the inner wall  173 ); the inner shaft  180  is composed of a conductive material; a substantially constant current or voltage source is coupled to a first end  167  of the outer housing  170 ; and a reference voltage node (e.g., ground) is coupled to the other end  166  of the outer housing  170 , then the stylus may function as a three terminal potentiometer with the contact point of the inner shaft  180  (e.g., the top portion  182 ) acting as the wiper terminal for the potentiometer. If the voltage of the inner shaft  180  is measured (e.g., by an analog to digital converter or other voltage sensor), Ohm&#39;s law can be employed to determine the location of the connection with the outer housing  170  if certain characteristics of the resistive material are known (e.g., does it vary linearly or logarithmically with distance). The top portion  182  in this example may be a depth plunger because it essentially helps determine the depth of the top portion  182  of the inner shaft  180  within the outer housing  170 . In this example, the inner shaft  180  may be biased in a biasing direction DB that is generally axial to the outer housing  170 , which may cause the inner shaft  180  to slide within the outer housing  170 . 
     It will be understood that many different electrical circuit variations may be employed together with the structure of the stylus  104  set forth herein to help determine a magnitude of a force exerted on the nib  122 , as indicated by a contact point of the inner shaft  180  within the outer housing  170 . For example, the constant current source could be applied to the second end  166  of the outer housing  170  rather than the first end  167 . Also, a substantially constant voltage source may be used in place of the substantially constant current source, in which case inner shaft  180  may act as a voltage divider relative to the inner surface  173  of the outer housing  170 . As still another example, a constant current or voltage source could be provided to one end of the inner shaft  180  rather than or in addition to providing the source to the outer housing  170 . In some embodiments, no constant current or voltage source is needed, and a circuit in the pre-processor circuit  198  of the stylus  104  may take a variable resistance provided by the inner shaft  180  and/or outer housing  170  and may determine a contact point within the outer housing  170  by measuring how long it takes a capacitance to charge and/or discharge through the variable resistance (essentially using two terminals of a potentiometer to create a variable resistance). In general, many different measurement nodes and reference voltages, nodes and currents may be employed to help generate one or more signals indicative of force applied to the nib  122  of the stylus  104  as measured by the interaction between the inner shaft  180  and the outer housing  170  of the stylus  104 . 
     With reference to  FIG. 9B  (and referring back to  FIGS. 7A and 7B ), and as another example, the top portion  182  of the inner shaft  180  may be lodged in the insulation layer  172  of the stylus  104 , thereby preventing movement of the top portion  182  relative to the outer housing  170 . In this example, the inner shaft  180  may be biased in a biasing direction D B  that is generally perpendicular to the outer housing  170 , which may cause the inner shaft  180  to bend and contact the inner surface  173  of the outer housing  170 . As with  FIG. 9A , the contact may be an electrical contact. 
     Referring now to  FIG. 9C  (and referring back to  FIGS. 6A, 6B, 7A, 7B ), in some embodiments, the inner shaft  180  of the stylus  104  may be configured to be biased in two biasing directions D B1 , D B2 . In these embodiments, the inner shaft  180  may include an insulator  187 , and the inner surface  173  of the outer housing  170  may be separated by a portion of the insulation layer  173  in order to form two, electrically isolated circuits both for measurement of the sliding movement of the top portion  182  of the inner shaft and for measurement of the bending movement of the core of the inner shaft  180 . In generally, using both axial and bending movement of the inner shaft  180  to determine a force exerted on the nib  122  may be more accurate in some instances than either alone. 
     Referring still to  FIG. 9C , when two electrically isolated circuits are used, measurements may be taken by one or more sensors in series and/or in parallel. In examples where parallel measurements are taken by between the two circuits, a diode may be included in the path of one circuit (e.g., in the pre-processor circuit  198  and/or in the inner shaft  180 ) in order to reduce the number of measurement or sensor nodes needed that are needed to take two independent measurements of voltage, current, resistance, etc. in the two circuits. 
     With reference to  FIG. 9D , an alternative implementation will now be described. The inner shaft  180  illustrated in  FIG. 9D  may be similar to those described above, but may additionally include a plurality of disks  184  that are electrically conductive. The diameter of the disks  184  may generally be 60-95% the diameter of the inner surface  173  of the outer housing  170 . A plurality of resistances  185  may be coupled between the electrically conductive plates  184 , and the core of the inner shaft  180  may be composed of an insulative material. In some embodiments, each of the resistances  185  may have a unique resistance value (e.g., 1 M-ohm, 500 K-ohm, etc.), whereas in other embodiments, one or more of the resistances  185  may have similar resistance values. 
     In operation, the inner shaft  180  illustrated in  FIG. 9D  functions much like the inner shaft  180  illustrated in  FIG. 9B  in that a force applied to the nib  122  of the stylus  104  causes the inner shaft  180  to bend towards the inner surface  173  of the outer housing  170  in a biasing direction D B . However, before the core of the inner shaft  180  is able to contact the outer housing  170 , one or more of the conductive disks  184  may contact the inner surface  173  of the outer housing  170 . In this manner, relatively clean measurements (of, e.g., resistance, voltage, current) may be obtained by a sensor coupled to the inner shaft  180  because the resistances  185  may be discrete and the contact point(s) of the conductive disks  184  may discretely contact the outer housing  170 . 
     Additional Considerations and Functionality 
     It should be noted that the input device described herein need not be used with a touch screen. Insofar as the input device may communicate wirelessly or otherwise with an associated computing device, the input device may be used on surfaces other than a touch-sensitive surface. For example, the input device may be used on paper, glass, canvas or any other material. The force-sensing properties would continue to operate as described herein. Further, since the position of the nib and/or shaft may vary as the nib runs or moves over a textured surface, the input to the associated computing device may vary correspondingly. When paired with appropriate software, this may permit an associated output to be influenced by the surface over which the nib moves. For example, a roughened surface may cause the stylus to experience variations in force, which may translate to a variable thickness output line as the nib moves. 
     Software may be configured to minimize or ignore miniscule changes in force exerted on the nib, so that very small variations are factored out. Likewise, software may be configured to enhance such variations, to provide a different output aesthetic than would otherwise be experienced from moving the input device across a given surface. 
     Input generated by motion of the input device may vary with the stroke of the input device. That is, the direction of stroke and surface on which a stroke is performed may vary the characteristics of an input, thereby varying the output. 
     When combined with position-sensing sensors, such as an internal accelerometer, gyroscope, and the like, embodiments described herein may be used to interact with computing devices in different and unique ways. Position sensing of the input device permits it to be used in a fashion similar to a pen or other writing utensil without requiring a specialized tracking surface to monitor the input device&#39;s position. Further, when combined with handwriting recognition software, the input device may permit written input for a computing system. 
     CONCLUSION 
     The foregoing description has broad application. For example, while examples disclosed herein may focus on stylus embodiments, it should be appreciated that the concepts disclosed herein may equally apply to substantially any other type of input device. Similarly, although the input device and receiving unit may be discussed with capacitive touch screens, the devices and techniques disclosed herein are equally applicable to other types of capacitive coupling systems and other, non-capacitive touch screens, and more generally to many types of haptic systems. Moreover, although the electrical circuits created by the structure of the styli described herein have primarily been described with reference to resistive-type measurement implementations, it will be understood that styli with capacitive-type or inductive-type measurement implementations are also within the scope of this disclosure and the appended claims. Accordingly, the discussion of any embodiment is meant only to be exemplary and is not intended to suggest that the scope of the disclosure, including the claims, is limited to these examples.

Metadata:
Filing Date: 20120914
Publication Date: 20170502
Grant Date: 20170502
Priority Date: 20120914
Inventors: ARMSTRONG-MUNTNER JOEL S.
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F3/044", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/03545", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0446", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0445", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0441", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0445", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0446", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/03545", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/03545", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0441", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 50273952