Abstract:
A handheld electronic device has an outer face in which a user display and a navigation touch pad are located. The touch pad is adapted to provide a user input for controlling at least one function of the electronic device. A plurality of touch sensors are located at predetermined locations about the area of the touch pad and detect touching by a user&#39;s finger in order to provide an output control signal. A light source is associated with each touch sensor. A control unit receives input from the touch sensors and activates each light source in turn as the associated touch sensor is touched by a user, so that the user receives visual feedback as they are controlling the device.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to navigation pads for personal electronic devices, such as handheld wireless communication devices or media players. 
       BACKGROUND 
       [0002]    There are many different types of user input or navigation devices for controlling personal electronic devices such as cellular phones, personal digital assistants, portable computers, media players, and the like. Such input devices generally comprise keypads, touch pads, touch screens, and the like. With a touch pad, movement of an input pointer on a screen corresponds to movement of a user&#39;s finger or a pointer over the surface of the touch pad. Navigation mechanisms in the form of keys for wireless communication devices (e.g., cellular phones) have been used in the past for navigating through and selecting menu items displayed on the wireless communication device. 
         [0003]    A need exists for an improved navigation mechanism in the form of a navigation pad for a handheld device, especially a handheld wireless communication device, that enhances the user experience with the wireless communication device. 
       SUMMARY 
       [0004]    An aspect of one embodiment involves a dial-type or circular navigation pad which lights up in a region touched by the user. In one embodiment, a light emitting diode (“LED”) light follows the user&#39;s finger as the user runs their finger around the edge of the circle. In other words, each region of the pad lights up as it is touched by the user&#39;s fingertip. This provides visual feedback as the user interacts with menu items on the screen. 
         [0005]    One embodiment comprises a cell phone or other portable wireless communication device having a touch pad for user input in controlling the device to make telephone calls or perform other functions. A series of light sources are provided at spaced intervals around the pad, each associated with a touch sensor location on the pad. In one embodiment, each light source comprises a radially extending light pipe with a light emitter such as a light emitting diode (LED) at one end of the pipe. The light pipes may be radially arranged in the same manner as an analog clock face, and may be controlled such that pairs of light pipes are illuminated to indicate current time when the touch pad is not in use. 
         [0006]    Other features and advantages of the present invention will become more readily apparent to those of ordinary skill in the art after reviewing the following detailed description and accompanying drawings. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The details of the present invention, both as to its structure and operation, may be gleaned in part by study of the accompanying drawings, in which like reference numerals refer to like parts, and in which: 
           [0008]      FIG. 1  is a front elevation view of a wireless phone according to one embodiment; 
           [0009]      FIG. 1A  is an enlarged view of the touch pad of the phone of  FIG. 1 , illustrating a finger running around the pad to light up light sources embedded in the pad while activating touch sensors for controlling a function of the phone; 
           [0010]      FIG. 2  is an exploded view of the annular touch pad of the phone of  FIG. 1 ; 
           [0011]      FIG. 3  is a top plan view of another embodiment of a sensor arrangement for the touch pad; 
           [0012]      FIG. 4  illustrates the sensor layer of the touch pad of either of the embodiments of  FIGS. 1 and 2  or  3 ; 
           [0013]      FIG. 5  is a simplified block diagram of a touchpad/display system according to one embodiment; 
           [0014]      FIG. 6  is a top plan view of the touch pad of  FIGS. 1 to 5  illuminated to provide a current time indication; and 
           [0015]      FIG. 7  is a top plan view illustrating an embodiment of the touch pad with graphical indicia corresponding to a rotary phone dial. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    Certain embodiments as disclosed herein provide for a navigation pad for controlling a hand-held or personal electronic device such as a cellular phone in which regions of the pad are arranged to light up in response to touch by a user&#39;s fingertip, and a method of using the same. 
         [0017]    After reading this description it will become apparent to one skilled in the art how to implement the invention in various alternative embodiments and alternative applications. However, although various embodiments of the present invention will be described herein, it is understood that these embodiments are presented by way of example only, and not limitation. As such, this detailed description of various alternative embodiments should not be construed to limit the scope or breadth of the present invention as set forth in the appended claims. 
         [0018]      FIG. 1  illustrates portable communication device or cell phone  100  having a clam-shell configuration with first housing portion  130  and second housing portion  140  pivotally connected to each other at hinge  150 . First housing portion  130  includes front  160  with display  170  and speaker  175  therein. Second housing portion  140  includes front wall  180  incorporating navigation pad  185  according to one embodiment. Although cell phone  100  is shown and described as having a clam-shell configuration, in alternative embodiments, phone  100  includes alternative configurations such as, but not limited to, a candy bar configuration, and a configuration where first housing portion  130  and second housing portion  140  are slidable relative to each other. Although navigation pad  185  in  FIG. 1  is the user input device of portable phone or cell phone  100  in the illustrated embodiment, such a pad is incorporated in other types of personal electronic devices in alternative embodiments, such as portable media players, game players, cell phones incorporating media players, portable digital assistants, and the like. 
         [0019]    Navigation or touch pad  185  is illustrated in more detail in  FIGS. 1A and 2  to  6 . Navigation pad or touch pad  185  is configured to provide one or more control functions for controlling operation of the device in which it is installed, such as portable or cellular phone  100  as in  FIG. 1 . The control function may be a scrolling function, in which a cursor or highlighted region scrolls down over menu items displayed on display screen  170  as the user runs their finger around pad  185 . When a desired menu item is reached, the user can select the item by touching a central control region or button, or in any other suitable manner such as tapping the finger on touch pad  185 . The displayed menu items may include all conventional menu selections for portable device  100  in which navigation pad  185  is installed. For example, when device  100  is a cell phone, menu items can include a phone directory and a list of telephone numbers through which a user can scroll in order to select a number to be called. Menu items may also include other selections such as voice mail, Internet, music playing, setup options, and the like, which can lead to other menus with specific selections within the category concerned. 
         [0020]    Navigation pad or touch pad  185  is a capacitative touch pad in one embodiment, but other types of touch pads are used in alternative embodiments, such as resistive touch pads and surface acoustic wave touch pads. Although touch pad  185  illustrated in the drawings is of annular or circular shape, it should be noted that the peripheral shape of pad  185  may be different in other embodiments, such as rectilinear, or non-circular curvilinear shapes. Although touch pad  185  is open at the center in the illustrated embodiment, touch pad  185  may be of circular or other shapes, without any central opening, in alternative embodiments. In the illustrated embodiment, touch pad  185  is of annular shape, and has touchable outer layer  190  of transparent or translucent material, electrode or sensor layer  192 , and circuit board or control layer  194 , as illustrated in  FIG. 2 . Touch pad is  185  configured to detect changes in capacitance as a user moves finger  195  in a rotational path about touch pad  185 , as illustrated in  FIG. 1A . 
         [0021]    Electrode or sensor layer  192  in one embodiment is illustrated in more detail in  FIG. 4  and has transparent substrate layer  196 , plural electrodes or capacitative sensors  198  in a predetermined pattern on one face of substrate layer  196 , and plural radially extending light pipes  200  mounted on the inner face of substrate layer  196  at predetermined angular spacings. Light pipes  200  may alternatively be embedded in layer  196 . Sensors  198  in one embodiment are arranged in radial lines corresponding to light pipe positions, as indicated in the drawings. In alternative embodiments, different numbers of radially extending light pipes and aligned sensors are provided, depending on the number of different control inputs desired. In the illustrated embodiment, light pipes  200  and aligned touch sensors  198  are provided at similar positions to a clock face, i.e., with twelve light pipes  200  at equal angular spacings of about thirty degrees around touch pad  185 . 
         [0022]    Each light pipe  200  is a transparent pipe lined with optical lighting film, having a light emitting diode (LED)  202  or other suitable light emitter at one end. In the illustrated embodiment, LEDs  202  are provided at the outer ends of light pipes  200 , although they may be located at the inner ends of light pipes  200  in alternative embodiments. LEDs  202  are suitably connected to control electronics (not illustrated) in layer  194  to be actuated when corresponding overlying sensor or sensors  198  are touched by a user of the device. It should be noted that sensors  198  are also connected to control electronics  194  in a manner known in the touch pad field. 
         [0023]    As illustrated in  FIG. 5 , control assembly  205  is coupled to touch pad  185  to receive inputs from sensors  198  and to supply corresponding signals to processor  206  of the portable device, such as cell phone  100 , and also to control operation of light pipes  200 . Control assembly  205  is incorporated in circuit board layer  194  of navigation or touch pad  185 . In alternative embodiments, control assembly  205  is a separate control unit mounted in phone or device housing  140  and connected to touch pad  185 . Control assembly  205  is an application specific integrated circuit (ASIC) or other type of circuit which monitors the outputs of sensors  198 , converts sensor outputs to an angular position and direction, supplies outputs to processor  206  for controlling a scrolling function on display  170 , and provides power to LEDs  202  associated with light pipes  200  based on detected sensor outputs, as described in more detail below. 
         [0024]    Control assembly  205  is configured such that light pipes  200  light up based on the position of user&#39;s finger  195  or another pointer device on navigation or touch pad  185 , as indicated in  FIG. 1A . The user runs finger  195  around pad  185  in a circular path, and this results in scrolling down of items in a menu displayed on screen  170 . In this embodiment, in addition to controlling a function of the personal electronic device requiring user input, such as the scrolling function, touch pad  185  lights up at the region touched by user&#39;s finger or pointer  195 , and the lighted regions follow the user&#39;s finger as the finger touches and runs around navigation or touch pad  185 . In  FIG. 1A , the illuminated region is light pipe  200 A which user&#39;s finger  195  is touching, and light pipes  200  indicated in dotted outline in  FIG. 1A  light up and go out successively as the user runs his or her finger around pad  185 , providing an attractive effect. Different shapes and sizes of lights may be provided in alternative embodiments. For example, instead of continuous radial light pipes  200  as illustrated, smaller, spaced LED lights are provided in alternative embodiments to light up at the radial position of finger or pointer  195 . Navigation pad  185  therefore provides visual feedback to a user during interaction with commands on the screen. 
         [0025]    In the first embodiment, touch sensors  198  are positioned on radially extending lines coincident with light pipes  200  so as to detect angular position of a finger on touch pad  185 .  FIG. 3  illustrates an alternative embodiment in which navigation or touch pad  250  has a modified sensor arrangement which includes sensors positioned to detect both angular and radial position of a user&#39;s finger or pointer on touch pad  185 . This embodiment includes light pipes  200  positioned in generally the same way as in the previous embodiment, as illustrated by the dotted lines in  FIG. 3 . Touch pad  250  is divided into sectors  252  defined by radial lines  254 , and each sector is in turn divided into separate radial sensor zones or areas  255  by spaced circular lines or divisions  256 . A touch sensor is located in each radial zone  255 . Each light pipe  200  extends radially through respective sector  252 . Alternatively, a separate LED is located beneath each zone  255 , so that only the zone  255  which a finger is touching lights up. Touch pad  250  is used to control different functions based on angular and radial touch position, such as a scrolling function based on sector  252  in which the finger is located, and another function such as volume control, brightness, or the like is provided based on radial position of the finger. 
         [0026]    When a user is operating the personal electronic device, such as cell phone  100 , and providing input on navigation pad  185 , light pipes  200  light up successively as the user runs his or her finger around pad  185 , as explained above. In one embodiment, control assembly  205  is configured to control navigation pad  185  to default to an analog clock when the dial or input function is not in use, as illustrated in  FIG. 6 . At any one time, control assembly  205  actuates two LEDs  205  to illuminate associated light pipes  200  at positions corresponding to analog clock hands indicating an actual time, as illustrated in  FIG. 6 . The clock indicates a time of five o&#39;clock in  FIG. 6 , by lighting up two light pipes  200  at the positions corresponding to 12 and 5 on an analog clock face. Control assembly  205  includes a clock to control actuation of successive light pipes in five minute increments based on actual time. 
         [0027]      FIG. 7  illustrates navigation pad  260  according to another embodiment which includes graphics or indicia associated with pad  260  for simulating a rotary telephone dial. As in the previous embodiments, pad  260  is of annular shape and has touch pad layers equivalent to those illustrated in  FIG. 2  for the first embodiment. Indicia on the outer layer comprise a series of small circles  262  at positions corresponding to dial positions on a rotary telephone dial. Indicia  264  on the face of the device around the periphery of pad  260  comprise the number and letter combinations for each dial position or circle  262 . LEDs and touch sensors are located in alignment with each circle  262  so that circles  262  light up successively as a user runs his or her finger over circles  262 . 
         [0028]    The above embodiments may be implemented by a combination of hardware and software, or by hardware or software alone. Although these embodiments were described in connection with a portable communication device such as a cellular phone or personal digital assistant (PDA), the navigation or touch pad may be incorporated for user input on any personal electronic device, such as any type of media player, a still or video camera, or the like, a laptop computer, or a phone or PDA which may also have media playing capabilities, Internet access capabilities, or the like. Although the touch pad is described as controlling a scrolling function, it may alternatively or additionally be configured to provide other control inputs to the portable device. The lighting up of regions of the pad successively as the user runs his or her finger over them enhances the user&#39;s experience when operating the device. 
         [0029]    The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles described herein can be applied to other embodiments without departing from the spirit or scope of the invention. Thus, it is to be understood that the description and drawings presented herein represent a presently preferred embodiment of the invention and are therefore representative of the subject matter which is broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other embodiments that may become obvious to those skilled in the art and that the scope of the present invention is accordingly limited by nothing other than the appended claims.