PATENT DOCUMENT

Publication Number: US-8294659-B2
Application Number: US-80442707-A
Country: US
Kind Code: B2

Title: Secondary backlight indicator for portable media devices

Abstract:
Systems and methods are provided for displaying icons directly on a display, such as an LCD, regardless of whether the display is ON. When the display is ON, a primary backlight may be used to illuminate the display. When the display is OFF, a secondary backlight may project light through the primary backlight to display one or more icons on the display. The displayed icons may be of various shapes, colors, and sizes.

Claims:
1. A method for presenting information on a display of an electronic device comprising primary and secondary backlight systems, the method comprising:
 selecting at least one region of the primary backlight system that defines at least one informational indicator; and 
 projecting light from the secondary backlight system through the at least one selected region of the primary backlight system, wherein the projected light forms the at least one informational indicator on the display. 
 
     
     
       2. The method of  claim 1 , wherein the display is turned OFF when the at least one informational indicator is formed on the display. 
     
     
       3. The method of  claim 1 , wherein the primary backlight system is turned OFF when the at least one informational indicator is formed on the display. 
     
     
       4. The method of  claim 1 , wherein the display and the primary backlight system are turned OFF when the at least one informational indicator is formed on the display. 
     
     
       5. The method of  claim 1 , wherein a shape of the at least one informational indicator is defined by the at least one region of the primary backlight system. 
     
     
       6. The method of  claim 1 , further comprising:
 filtering the light projected from the secondary backlight system. 
 
     
     
       7. The method of  claim 1 , wherein projecting light from the secondary backlight system comprises:
 selectively providing light from either a first light source or a second light source of the secondary backlight system. 
 
     
     
       8. The method of  claim 1 , further comprising:
 determining a status of the electronic device; and 
 displaying a particular informational indicator based on the determined status. 
 
     
     
       9. The method of  claim 1 , further comprising:
 receiving a user input; and 
 displaying a particular informational indicator based on the received user input. 
 
     
     
       10. The method of  claim 1 , further comprising:
 selectively guiding the projected light through the at least one region of the primary backlight system. 
 
     
     
       11. The method of  claim 1 , wherein the projecting light comprises selectively projecting light from a subset of light sources of the secondary backlight system through the at least one region. 
     
     
       12. The method of  claim 1 , further comprising:
 blocking the projected light from being projected through another region of the primary backlight system. 
 
     
     
       13. The method of  claim 1 , further comprising:
 selecting the at least one region from a plurality of regions of the primary backlight system. 
 
     
     
       14. A method for presenting information on a display of an electronic device comprising primary and secondary backlight systems, the method comprising:
 turning OFF the display and the primary backlight system; 
 determining a status of the electronic device that is independent of the status of the primary backlight system; 
 selecting a region of the primary backlight system based on the determined status, wherein the region defines at least one informational indicator; and 
 selectively turning ON the secondary backlight system to project light through the selected region based on the determined status to display the at least one informational indicator on the display while the display and primary backlight system are turned OFF. 
 
     
     
       15. The method of  claim 14 , wherein the determined status comprises at least one of a playback status of media on the electronic device and a download status of media to the electronic device. 
     
     
       16. A method of presenting one of a plurality of informational indicators on a display of an electronic device comprising primary and secondary backlight systems, wherein the secondary backlight system comprises a plurality of light sources, the method comprising:
 turning OFF the display; 
 selecting a region of the primary backlight system that defines the one of the plurality of informational indicators; and 
 selectively projecting light from a subset of the plurality of light sources through the selected region of the primary backlight system to selectively display the one of the plurality of informational indicators on the display while the display is turned OFF. 
 
     
     
       17. The method of  claim 16 , wherein the primary backlight system comprises a plurality of regions for light to project through from the secondary backlight system, and wherein each informational indicator is associated with one of the plurality of regions. 
     
     
       18. The method of  claim 17 , the method further comprising:
 filtering the light provided by the subset of the plurality of light sources to allow light through one of the plurality of regions. 
 
     
     
       19. The method of  claim 16 , wherein each informational indicator is associated with a set of properties, the method further comprising:
 determining the set of properties associated with an informational indicator that is to be displayed; and 
 selectively projecting light from at least one of the plurality of light sources that can provide light according to the set of properties. 
 
     
     
       20. The method of  claim 19 , wherein the set of properties includes at least one of color, intensity, blinking pattern, blinking speed, and location. 
     
     
       21. The method of  claim 16 , wherein light is selectively provided from multiple light sources to create a motion icon. 
     
     
       22. The method of  claim 16 , further comprising:
 turning ON and OFF a selected light source of the plurality of light sources repeatedly at a predetermined rate. 
 
     
     
       23. The method of  claim 16 , further comprising:
 adjusting an intensity of a selected light source of the plurality of light sources. 
 
     
     
       24. The method of  claim 16 , further comprising:
 filtering light provided by the subset of the plurality of light sources to shape the displayed informational indicator. 
 
     
     
       25. An electronic device, comprising:
 a display; 
 a primary backlight system comprising a plurality of semitransparent regions, wherein a first semitransparent region has a first shape that defines an icon, the primary backlight system operative to illuminate a substantially full portion of the display; and 
 a secondary backlight system operative to selectively project light through the first semitransparent region selected from the plurality of semitransparent regions onto the display while the display and the primary backlight system are turned OFF, wherein the projected light forms the icon of the first shape on the display. 
 
     
     
       26. The electronic device of  claim 25 , wherein the primary backlight system comprises one or more light sources for generating light to illuminate the substantially full portion of the display. 
     
     
       27. The electronic device of  claim 25 , wherein the primary backlight system comprises a light pipe for transporting light evenly across the substantially full portion of the display. 
     
     
       28. The electronic device of  claim 25 , wherein the primary backlight system comprises a reflective layer for directing light toward the display. 
     
     
       29. The electronic device of  claim 25 , wherein the secondary backlight system comprises one or more light sources for lighting a portion of the display. 
     
     
       30. The electronic device of  claim 29 , wherein the one or more light sources are in a single device. 
     
     
       31. The electronic device of  claim 25 , wherein the secondary backlight system comprises a light pipe for transporting light to at least a location near the semitransparent region. 
     
     
       32. The electronic device of  claim 25 , wherein the secondary backlight system comprises a reflective layer for directing light through the at least one semitransparent region. 
     
     
       33. The electronic device of  claim 25 , further comprising a filtering system, wherein the filtering system allows light of certain properties to reach predetermined areas of the display. 
     
     
       34. An electronic device, comprising:
 a display; 
 a primary backlight system including at least one primary light source, a primary light pipe having a first and second side, and a primary reflective layer comprising at least one semitransparent region that has a first shape, the primary reflective layer having a third and fourth side, wherein the second side of the primary light pipe is mated to the third side of the primary reflective layer, and wherein the primary light source is operative to project light to at least the first side of the primary light pipe; and 
 a secondary backlight system including at least one secondary light source, at least one secondary light pipe having fifth and sixth sides, and at least one secondary reflective layer having seventh and eight sides, wherein the sixth side of the at least one secondary light pipe is mated to the seventh side of the at least one secondary reflective layer, and wherein the at least one secondary light source is operative to selectively project light to at least the fifth side of the at least one secondary light pipe, and the fifth side faces the fourth side of the primary reflective layer, and wherein the light projected by the at least one secondary light source projects through the at least one semitransparent region to form an informational indicator of the first shape on the display while the display and the primary backlight system are turned OFF. 
 
     
     
       35. The electronic device of  claim 34 , wherein each of the at least one secondary light source provides light though a subset of the at least one semitransparent region. 
     
     
       36. The electronic device of  claim 34 , further comprising a filtering system mated to the fourth and fifth sides. 
     
     
       37. The electronic device of  claim 36 , wherein the filtering system is operative to allow light projected from the secondary backlight system to reach one of the at least one semitransparent region. 
     
     
       38. The electronic device of  claim 36 , wherein the filtering system comprises a different filter associated with each of the at least one semitransparent region. 
     
     
       39. The electronic device of  claim 36 , wherein the filtering system comprises color filters. 
     
     
       40. The electronic device of  claim 34 , wherein the secondary light source is positioned near a perimeter of the secondary light pipe. 
     
     
       41. The electronic device of  claim 34 , wherein the secondary light source is positioned near the semitransparent region.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to electronic devices and more particularly to providing display indicators for electronic devices. 
     Portable electronic devices such as digital electronic devices (e.g., music players and video players) are known. These devices are typically powered by one or more batteries. Batteries store a fixed amount of energy. Therefore, efficient use of the fixed energy source is desirable in order to maximize the length of time between battery replacements or recharges. 
     One way to conserve energy is to turn off a display (e.g., LCD) of a portable electronic device when the user does not need or want to view media. For example, the display of a music player may be turned off after the user is done choosing music to play. However, if the display of an electronic device is turned off, it may be difficult or impossible for a user to determine the status of the device, or to identify that the electronic device itself is still on. Thus, it is desirable to provide one or more low-power consuming indicators to inform the user of the status of the device. 
     Known indicators, however, are provided through a hole in the casing of an electronic device, where a low-power light may be generated to show through the hole. However, this approach requires extra assembly or packaging considerations that may be expensive and may detract from the aesthetic appeal of the device. Therefore, there is a need for electronic devices that provide indicators directly on the display. 
     SUMMARY OF THE INVENTION 
     Systems and methods are provided for displaying information on the display of an electronic device, such as a portable electronic device. 
     The display system of an electronic device can include a display (e.g., an LCD), a primary backlight system, and a secondary backlight system. Each of these components may be ON or OFF. When the display is ON, it can provide media, such as video clips or graphics. When the primary or secondary backlight systems are ON, they may generate light to illuminate the display. 
     The display system may have multiple operating modes. The display system may be in a first operating mode when a user wants to view media on the display. In this mode, the display may be turned ON to display the desired media. The primary backlight system may also be turned ON to allow the user to easily see the contents of the display. Alternatively, the primary backlight system may remain OFF, and the user may rely on external lighting to view the contents of the display. The display system may enter a second, less power consuming mode when a user does not want to view media. In this mode, the display may be turned OFF. Also, because no content is available for the user to view, the primary backlight system may also be turned OFF. 
     In the second operating mode, even though the display is OFF, information such as a status indicator can be provided on the display. To provide an icon on the display of the electronic device that is indicative of the status of the device, the secondary backlight system may be turned ON. The secondary backlight system may be separated from the display by the primary backlight system. Thus, the light provided by the secondary backlight system may be projected through one or more transparent or semitransparent regions of the primary backlight system to reach the display. The primary backlight system may block light from the secondary backlight system except for those one or more regions. Thus, the size and shape of the status indicator may be set by sizing and shaping the transparent or semitransparent regions of the primary backlight system. In addition to setting the size and shape of the icon, the color of the icon may also be set by adjusting the color of the light provided by the secondary backlight system. 
     In accordance with another aspect of the present invention, a display system may provide multiple status indicator icons or information displays of any suitable size, shape, and color, and may selectively choose between them. In some embodiments, the icons may be displayed at different locations on the display. In these embodiments, each icon may correspond to a separate transparent or semitransparent region of the primary backlight system. Thus, during operation, the secondary backlight system may selectively guide light toward certain regions of the primary backlight such that only selected icons are shown on the display. To ensure that the light from the secondary backlight system only reaches the proper region or regions on the primary backlight system and does not leak to other regions, the display system may additionally include one or more color filter layers between the primary and secondary backlight systems. Each color filter layer may include color filters that may only transmit certain colors and may block other colors. Thus, if each icon is associated with a different color, the color filters may ensure that colored light guided from the secondary backlight system toward a particular transparent or semitransparent region of the primary backlight system does not leak through another region. 
     In some embodiments, multiple status indicator icons may be displayed at substantially the same location on the display. To vary the shape or size of each indicator, the shape and size of the color filters may be varied rather than the shape and size of the transparent or semitransparent regions of the primary backlight system. For example, color filters of different shapes and with different properties may be superimposed on each other. Thus, the shape of an icon on the display may depend on the color of light provided by the secondary backlight. This technique may also be used for icons that are displayed side-by-side. 
     In accordance with another aspect of the present invention, the one or more displayed icons may be dynamic. For example, a light source within the secondary backlight system may be turned ON and OFF to create a blinking effect, or the intensity of the light may be varied through, for example, pulse-width-modulation. Also, the one or more icons may be displayed in short time intervals (e.g., for half a second every five seconds) in order to conserve battery power. 
     Therefore, each status indicator provided by the electronic device, whether located at different locations on a display or at substantially the same location, may be associated with light having particular properties. For example, each indicator may have a particular color, blinking speed, or light intensity. These properties may be programmed into the electronic device by the user, or may be hard-coded or hard-wired into the system. Thus, when the secondary backlight is turned ON (e.g., when switching to the second operating mode as discussed above), the properties of the light provided by the secondary backlight system may depend on the status of the device. Also, if the status of the electronic device changes while the secondary backlight is ON, the properties of the light provided by the secondary backlight system may change to reflect the new status. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The above and other objects and advantages of the invention will be apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout, and in which: 
         FIG. 1  shows a block diagram of an electronic device in accordance with an embodiment of the present invention; 
         FIGS. 2A and 2B  show illustrative display screens in accordance with an embodiment of the present invention; 
         FIGS. 3A and 3B  show an illustrative block diagram of a display system in accordance with an embodiment of the present invention; 
         FIGS. 4A and 4B  show more detailed, yet still simplified, diagrams of a display system similar to the display system of  FIG. 3 , but from a side perspective, in accordance with an embodiment of the present invention; 
         FIGS. 5A and 5B  show more detailed, yet still simplified, diagrams of a display system similar to the display system of  FIG. 3 , but from a side perspective, in accordance with an embodiment of the present invention; 
         FIG. 6  shows a perspective view of a display system similar to  FIGS. 4A and 4B  in accordance with an embodiment of the present invention; 
         FIG. 7-10A  show display systems with multiple indicators and multiple color filters in accordance with some embodiments of the present invention; 
         FIGS. 10B and 10C  show color filter configurations in accordance with an embodiment of the present invention; 
         FIG. 11  shows an illustrative flow chart for changing the state of a display system from ON to OFF in accordance with an embodiment of the present invention; 
         FIG. 12  shows an illustrative flow chart for changing the state of a display system from OFF to ON in accordance with an embodiment of the present invention; 
         FIG. 13  shows an example of how one of the steps of  FIG. 12  can be implemented in accordance with an embodiment of the present invention; and 
         FIG. 14  shows an illustrative flow chart for changing the properties of light provided by a secondary backlight system in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a simplified block diagram of illustrative electronic device  100 . Electronic device  100  may include processor  102 , storage device  104 , user interface  108 , display system  110 , CODEC  112 , bus  118 , memory  120 , and communications circuitry  122 . Processor  102  can control the operation of many functions and other circuitry included in electronic device  100 . Processor  102  may drive display  110  and may receive user inputs from user interface  108 . 
     Storage device  104  may store media (e.g., music and video files), software (e.g., for implementing functions on device  100 ), preference information (e.g., media playback preferences, backlight preferences), lifestyle information (e.g., food preferences), exercise information (e.g., information obtained by exercise monitoring equipment), transaction information (e.g., information such as credit card information), wireless connection information (e.g., information that may enable device  100  to establish a wireless connection such as a telephone connection), subscription information (e.g., information that keeps track of podcasts or television shows or other media a user subscribes to), telephone information (e.g., telephone numbers), and any other suitable data. Storage device  104  may include one or more storage mediums, including for example, a hard-drive, permanent memory such as ROM, semi-permanent memory such as RAM, or cache. 
     Memory  120  may include one or more different types of memory which may be used for performing device functions. For example, memory  120  may include cache, Flash, ROM, and/or RAM. Memory may be specifically dedicated to storing firmware. For example, memory may be provided for storing firmware for device applications (e.g., operating system, user interface functions, and processor functions). 
     Bus  118  may provide a data transfer path for transferring data to, from, or between storage device  104 , communications circuitry  122 , memory  120 , and processor  102 . Coder/decoder (CODEC)  112  may be included to convert digital audio signals into an analog signal, which may be provided to an output port (not shown). 
     User interface  108  may allow a user to interact with device  100 . For example, user input device  108  can take a variety of forms, such as a button, keypad, dial, click wheel, or touch screen. Communications circuitry  122  may include circuitry for wireless communication (e.g., short-range and/or long-range communication). For example, the wireless communication circuitry may be wi-fi enabling circuitry that permits wireless communication according to one of the 802.11 standards or a private network. Other wireless network protocol standards could also be used, either as an alternative to the identified protocols or in addition to the identified protocols. Another network standard may be Bluetooth. 
     Display system  110  may present media, including graphics, text, and video, to a user. Display system  110  can include display  124 , which may be a liquid crystal display (LCD), a touch screen display, or any other suitable display for displaying media. Display system  110  can also include primary backlight system  126  and secondary backlight system  128  to illuminate display  124 . Backlight systems  126  and  128  may each include one or more light-emitting diodes (LEDs), light bulbs, or any other suitable light sources. Backlight systems  126  and  128  may each also include other components for transporting or guiding light provided by the one or more light sources. For convenience, these and other backlight systems will be referred to simply as “backlights,” but should not be confused with the light sources that can be included in the backlight. 
     Display  124 , primary backlight  126 , and secondary backlight  128  may each be driven by processor  102 , by processing circuitry internal to display system  110  (not shown), or by a combination of the two. These processors may process the media displayed by display  124 . Also, the processors may selectively turn each of display  124 , primary backlight  126 , and secondary backlight  1280 N or OFF. Display  124  may only display media when it is ON. Primary backlight  126  and secondary backlight  128  may only provide light when they are ON. 
     In one embodiment, device  100  may be a portable computing device dedicated to processing media, such as audio and video media. For example, device  100  may be an electronic device (e.g., MP3 player), a game player, a remote controller, a portable communication device, a remote ordering interface, an audio tour player, or other suitable personal device. 
     In another embodiment, device  100  may be a portable device dedicated to media processing and telephone functionality in a single integrated unit. Device  100  may be battery-operated and highly portable so as to allow a user to listen to music, play games or video, record video or take pictures, place and take telephone calls, communicate with others, control other devices, and any combination thereof. In addition, device  100  may be sized such that it fits relatively easily into a pocket or hand of the user. By being handheld, device  100  may be relatively small and easily handled and utilized by its user, and thus may be taken practically anywhere the user travels. 
       FIGS. 2A and 2B  show illustrative display screens  200  and  202  that may be provided by a display system, such as display system  110  ( FIG. 1 ), of an electronic device. Display screen  200  of  FIG. 2A  may be provided when a user wants to view media. In particular, the contents of display screen  200  may be provided by a display (e.g., display  124 ) of the display system. The content provided by the display may include information about media that is playing. For example, if the electronic device is a music player, display screen  200  may include information related to a song that the electronic device is playing. The information may include text  208  (e.g., the title of the song, the name of the artist and/or album), graphics  204  (e.g., the cover of the album, picture of the artist), and any other suitable information. Display screen  200  may also include actual media, rather than just information, such as a video clip or a music video. In addition, display screen  200  may be illuminated by a backlight (e.g., primary backlight  126 ) to allow a user to view the media or media information on display screen  200  regardless of the external lighting conditions. Alternatively, the backlight may be turned OFF to conserve power in the electronic device, and the user may rely on external light to view the display. 
     Display screen  202  of  FIG. 2B  may be provided by the electronic device when the user does not want to view media or the device detects a situation where the user cannot view the content even if it is being displayed, such as when the device is in the user&#39;s pocket or bag. In  FIG. 2B , the display (e.g., display  124 ) is turned OFF. Display screen  202  may include icon/indicator  206  to indicate the status of the device. Indicator  206  may be a green light projected onto a portion of the display, and may be triangularly shaped, a shape often used as a “play” icon, to indicate that media is currently playing. It should be understood that indicator  206  may be of any suitable shape, size, and color, and may be used for any suitable reason. Furthermore, although only one indicator is shown on display screen  202 , there may be more than one indicator on the display. To conserve power, the remaining portions of display screen  202  may appear substantially the same as when the electronic device is OFF. That is, a backlight typically used to illuminate a substantial portion of the display (e.g., primary backlight  126 ) may be turned OFF whenever display screen  202  is provided. 
       FIGS. 3A and 3B  show a high level block diagram of a display system in accordance with embodiments of the present invention.  FIGS. 3A and 3B  show the display system operating in two different modes, where  FIG. 3A  shows a mode able to provide display screen  200  ( FIG. 2A ), and  FIG. 3B  shows a mode able to provide display screen  202  ( FIG. 2B ). For simplicity, when the display system is operating as shown in  FIG. 3A , the display system may be referred to as ON—that is at least the display is turned ON. When the display system is operating as shown in  FIG. 3B , the display system may be referred to as OFF—that is at least the display is turned OFF. 
     The display system may include display  304  (e.g., display  124 ), primary backlight  306  (e.g., primary backlight  126 ), and secondary backlight  308  (e.g., secondary backlight  128 ). For clarity, eye  302  shows a point of view from which a viewer can view the display system. In  FIG. 3A , display system  304  and primary backlight  306  are ON, while secondary backlight  308  is OFF. Therefore, display  304  may provide media and media information, such as display screen  200  of  FIG. 2A , to a viewer. To illuminate the display, primary backlight  306  may project light  310  toward display  304 . Primary backlight  306  may provide light  310  such that the intensity of the light is distributed substantially evenly across display  304 . In other embodiments, primary backlight  306  may be OFF and does not provide light  310 . In these embodiments, content provided by display  304  may be viewable even though primary backlight  306  is OFF. 
       FIG. 3B  shows a display system operating to provide a display screen similar to display screen  202  in  FIG. 2B . In  FIG. 3B , display  304  is OFF, and does not provide content to a viewer. Primary backlight  306  is also OFF, and does not illuminate display  304 . Secondary backlight  308  is ON, and can generate light  312 , which can be projected toward primary backlight  306 . Primary backlight  306  may allow a portion of light  312  to pass through to display  304 . In particular, primary backlight  306  may include region  320  that permits light to pass through, and may block all other light provided from secondary backlight  308 . Region  320  may be shaped and sized in any suitable way to permit light of any suitable shape and size to pass through. For example, region  320  may be triangularly shaped. In this way, light  314  that is permitted to travel through the primary backlight may create a triangular “play” indicator, icon  316 , on display  304 . The remaining areas of display  304  may remain dark, since no light from the secondary backlight may reach those areas. 
       FIGS. 4A and 4B  show a detailed embodiment of  FIGS. 3A and 3B , respectively. Primary backlight  406  can include light source  418 , light pipe  412 , and reflective layer  414 . Secondary backlight  408  can include light source  430 , light pipe  436 , and reflective layer  438 . 
     Referring first to primary backlight  406 , light source  418  can include one or more LEDs or light bulbs, or any combination of suitable sources capable of generating light. Block diagram  400  in  FIG. 4A  shows primary backlight  406  in an ON state with light source  418  generating light. Block diagram  402  in  FIG. 4B  shows primary backlight  406  in an OFF state. Similarly, block diagram  400  shows secondary backlight  408  in an OFF state, while block diagram  402  shows secondary backlight  408  in an ON state. 
     Primary backlight  406  ( FIGS. 4A and 4B ) can also include light pipe  412  to transport light along the length and width of display  404 . Light pipe  412  may ensure that light  422  emitted from light source  418  is evenly distributed across display  404  even though the light source is located near the bottom of display  404 . To effectively transport light, light pipe  412  may include one or more layers of any suitable materials. In addition, light pipe  412  may have any suitable contour and may be of any suitable thickness. Furthermore, the contour and thickness may vary at different portions of light pipe  412 . 
     Reflective layer  414  may reflect light generated by light source  418  toward display  404 . To efficiently utilize the light from light source  418 , reflective layer  414  may reflect a substantial proportion of the light from light source  418  that would otherwise have traveled away from display  404 . Reflective layer  414  may also block a substantial proportion of light generated by secondary backlight  408 . Reflective layer  414  may substantially block light projected from light source  430  except for any light traveling toward a semitransparent region of the layer, region  416 . Thus, for light traveling from secondary backlight  408 , reflective layer  414  may be considerably more transitive at region  416  than its remaining portions. Therefore, in some embodiments, region  416  may transmit light in one direction considerably more easily than the other, namely from secondary backlight  408  to display  404 , but not as well in the other direction. This is shown in  FIGS. 4A and 4B , where light  422  from the primary light source  418  is substantially reflected, while light  434  from the secondary backlight  408  is substantially transmitted. In other embodiments, region  416  may allow light to travel more equally in both directions. If the size of region  416  is small compared to the total size of the reflective layer, the loss of reflected light from the non-reflective portion may have little or no effect. 
     Semitransparent region  416  may be created in any suitable way. In some embodiments, semitransparent region  416  may be etched into the reflective layer, and, if necessary, light pipe  412 . In other embodiments, region  416  may be made using a different material than the remainder of reflective layer  414 . 
     Secondary backlight  408  can include light source  430 , light pipe  436 , and reflective layer  438 . Light source  430  may be one or more of any suitable light-emitting devices, such as one or more LEDs. In some embodiments, because secondary backlight  408  may be used to project light onto a portion of display  404  rather than the entire display, less light may be generated by light source  430  than light source  418 . Thus, light source  430  may include fewer lighting-emitting devices than light source  418 , may use dimmer and less power-consuming devices, or may utilize any other technique for generating a suitable amount of light. 
     Secondary light pipe  436  can transport light emitted from light source  430  along the pipe. Light pipe  436  may need to transfer light to the portion of the light pipe directly behind the semitransparent region of primary reflective layer  414 , where light may be transmitted through semitransparent region  416  and onto display  404 . In some embodiments, light pipe  436  may be shaped or designed to effectively transport light to the areas of the light pipe where light may eventually reach the display. If desired, light pipe  436  may be sized to only span the distance from light source  430  to semitransparent portion  416 . In other embodiments, light pipe  436  may transport light such that it is spread substantially evenly across a substantial portion of primary reflective layer  414 . These embodiments may be used if the location of region  416  is unknown or may vary between different display systems. 
     Reflective layer  438  of secondary backlight  408  directs light transported by light pipe  436  through portion  416  of the primary reflective layer. That is, it reflects light toward display  304 . Because only a portion of display  404  is lighted by the secondary backlight, in some embodiments, only the area of reflective layer  438  directly behind portion  416  may be reflective. The remainder of layer  438  may be non-reflective or may not be present at all. 
       FIGS. 4A and 4B  show one way that the block diagrams of  FIGS. 3A and 3B  may be implemented.  FIGS. 5A and 5B  show alternate ways to implement the secondary backlight. In particular,  FIGS. 4A and 4B  show the secondary light sources situated at other suitable locations behind the primary backlight. In  FIG. 5A , light source  504  is situated directly behind the semitransparent region  506  of the primary backlight. In this embodiment, the secondary backlight can include only light source  504 , because light source  504  may efficiently transmit light through portion  506  by itself. Alternatively, the secondary backlight may additionally include a light pipe and a reflective layer. 
     The secondary light source may be located at a predetermined position (e.g., near the top of the display system, as shown in  FIG. 5B ). The secondary backlight may include light pipe  510  and reflective layer  512 , which may have one or more of the properties discussed above. The shape and other properties of light pipe  510  and reflective layer  512  may be selected such that light provided by light source  508  may be efficiently transmitted through region  514  of the primary backlight. Thus, secondary light source may be located at any suitable position. Although not shown, the primary light source may also be located at any suitable position, and not just near the bottom of the display. 
       FIG. 6  shows an exploded view of a portion of a display system similar to that of  FIG. 4B , but from a different perspective. The display system is oriented such that the light pipe and reflective layer are viewable approximately head on. For convenience, the light pipe and reflective layers are shown as a single layer. Thus, the primary backlight can include light sources  604  and primary layer  602 , where the primary layer may include both a light pipe and a reflective layer. The secondary backlight may include light source  622  and secondary layer  620 , where layer  620  may also include a light pipe and a reflective layer. The primary backlight is shown to be OFF, while the secondary backlight is shown to be ON. Thus, light source  622  of the secondary backlight can generate light and project it toward the primary layer. Of this light, only light  610  traveling through semitransparent region  606  may pass through the primary layer and reach the display. The remaining portions of primary layer  602  may block light projected from the secondary backlight. 
     The display system in  FIG. 6  may be used to display an icon on a display (not shown) of any suitable size and shape. The shape of the icon may be tailored for graphic association. For example, the icon may be triangular, a shape that typically represents “play,” or the icon may be circular, a shape that is typically associated with “record.” Thus, the shape of an icon may be used to represent the meaning of the icon. The icon may be shaped and sized by shaping and sizing semitransparent region  606  of the primary layer. That is, light  610  projected onto the display map can be shaped according to the light allowed through the primary layer. 
     An icon displayed on the display in  FIG. 6  (not shown) may also be of any suitable color. A colored icon may be used for color association. For example, green, which is typically associated with “go,” may be used for a “play” icon, while red, typically associated with “stop,” may be used for a “pause” icon (not shown). Thus, the color of an icon, in addition to or instead of the shape of the icon, may be used to represent the meaning of the icon. To create a colored icon, secondary light source  622  may emit light of any suitable color. For example, light source  622  may include a green LED for a “play” icon, or light source  622  may include a red LED for a “pause” icon. 
     The position of the components in  FIG. 6  is merely illustrative. It should be understood that the position of light source  622  may be adjusted vertically, similar to the manner in which the secondary light source of  FIGS. 5A and 5B  can be adjusted as discussed above. In addition to adjusting the vertical position of light source  622  in  FIG. 6 , the horizontal position may also be adjusted. For example, rather than being positioned at the center of layer  620 , light source  622  may be placed at the same horizontal location as portion  606  (e.g., towards the left of the layer). Similarly, light sources  604  of the primary backlight may be arranged at any suitable horizontal or vertical location in front of the primary backlight layer. Layers  602  and  620  may also be of any suitable size. Primary layer  602  can be substantially the same size as the display, so that light may be transported and reflected to all parts of the display. In some embodiments, secondary layer  620  may be smaller than primary layer  602 . For example, secondary backlight layer  620  may be substantially the same width as the width of semitransparent portion  606 . 
     In accordance with another aspect of the present invention, multiple icons may be projected onto a display (e.g., display  124 ). Various embodiments of display systems with multiple icons are described below in connection with  FIGS. 7-9  and  10 A. Each of these embodiments are shown with the display system OFF. That is, the display and primary backlight may be OFF and the secondary backlight(s) may be ON to show how light may be passed from the secondary backlight(s) to the display.  FIGS. 7-9  show multiple icons positioned side-by-side, and  FIG. 10A  shows multiple icons superimposed on one another. Each of the icons in any of the embodiments may be of one or more colors. Thus, color filters, which filter out certain colors or only permit certain colors to pass, may be utilized in some or all of these embodiments. 
     Referring first to  FIG. 7 , an exploded view of a portion of display system  700  is shown for projecting multiple side-by-side icons onto a display. In this embodiment, the light for each icon is provided by a separate light source. Therefore, rather than a single secondary backlight, multiple secondary backlights, such as backlights  746  and  748 , can be provided to generate and guide light from their respective light sources to their respective indicators. It is understood that backlights  746  and  748  are referred to as separate secondary backlights for simplicity, but may instead be considered in combination as a single secondary backlight. As shown in  FIG. 7 , two icons may be projected onto the display: a “play” icon and a “pause” icon. The light for the play icon is supplied by backlight  748 , and the light for the pause icon is supplied by backlight  746 . The play and pause shaped indicators may be etched at locations  708  and  710  of primary layer  702 , respectively, or at any other suitable location on the primary layer. Light source  744  of backlight  746  may generate light for the pause icon, and secondary layer  740  may guide this light toward pause icon region  710 . Another light source (not shown) associated with backlight  748  may provide light for the play icon, and secondary layer  742  may guide this light toward play icon region  708 . 
     In some embodiments, the light sources for secondary backlights  746  and  748  may be the same color. In other embodiments, secondary backlights  746  and  748  may provide light of different colors. For example, secondary backlight  746  may provide red light for the pause indicator, and secondary backlight  748  may provide green light for the play indicator. In these embodiments, color filters may be used to prevent light provided by one secondary backlight from providing light for an icon associated with another secondary backlight. Thus, a color filter layer with color filters for each icon may be provided between the primary backlight layer and the secondary backlight layers. For display system  700 , the color filter layer may include color filter  724 , placed behind pause etch  710 , and color filter  722 , placed behind play etch  708 . Color filter  724  may be used to allow only red light (e.g., from light source  744 ) to pass to the pause etch, and may block green light from the pause etch. Color filter  722  may be used to prevent any light from light source  744  from reaching the play etch by, for example, filtering out red light or absorbing all but green light. It should be understood that  FIG. 7  and its description above is merely illustrative. Thus, more than two icons may be provided, and each of any suitable size, shape, and color. 
     It may be further contemplated that color filter layer  720  in  FIG. 7  may be omitted from the display system without substantially changing the look or functionality of the indicators. For example, if little or none of the light generated by light source  744 , intended to light a pause icon, reaches play indicator region  708 , and vice versa, then color filters  722  and  724  may not be necessary. 
       FIG. 8  shows another simplified embodiment of a partial display system with multiple indicators. In this embodiment, a single secondary backlight may be used to provide light for multiple side-by-side icons. Thus, device  800  can include a single secondary backlight with light source  842  and backlight layer  840 . Light source  842  may provide light of different colors, and the color of the provided light may determine whether the light is passed through the play and pause etch on primary layer  802 . To provide light of different colors, light source  842  may be a colored LED that may change between two or more colors by, for example, changing the direction of current flow through the LED. Thus, light source  842  may include an LED that may generate either green or red light to provide either the color associated with “play” or the color associated with “pause.” Alternatively, light source  842  may include multiple, single-colored LEDs, where each LED emits a different color, and the LEDs may be selectively turned ON and OFF. Thus, a green LED may used to indicate that media is playing, while a red LED may be used to indicate that the media has been paused. 
     Color filter layer  820  may be included between the primary and secondary backlights to allow only the intended indicator(s) to be displayed. Otherwise, every icon would be displayed when the secondary backlight is turned ON. Color filter layer  820  may include a different type of color filter for each of the semitransparent regions on the primary backlight. Here, color filter layer  820  includes color filters  822  and  824 . Color filter  822  may be used to allow only green light to project through play etch  808 . Color filter  824  may be used to allow only red light to project through pause etch  810 . Thus,  FIG. 8  shows light source  842  generating green light, because light is shown to reach only play etch  808 . Therefore, to display a play icon, green light may be supplied by the secondary backlight and projected towards both color filters  822  and  824 . Of the supplied light, only light  848  transmitted toward color filter  822  associated with the play icon may be passed through color filter layer  820 . Light  846  that otherwise may have reached pause etch  810  is blocked by color filter  824 . Then, of the light that passes through the color filter layer, only the portion of the light that is transmitted toward play etch  808  may be passed to the display (e.g., light  814 ). 
     Although only two indicators are shown in partial display system  800 , it should be understood that any suitable number of indicators may be provided using this configuration. For example, the secondary backlight may include one or more secondary light sources that may collectively provide any suitable number of colors. In addition, the color filter layer may provide any suitable number of color filters to selectively pass certain colors. 
       FIG. 9  shows another exploded view of a portion of display system  900  with multiple indicators, which combines the embodiments of  FIGS. 7 and 8 . In particular, device  900  has multiple secondary backlights, each of which can provide light for multiple indicators. As with  FIG. 7 , the multiple secondary backlights may also be considered a single secondary backlight with multiple parts, but are referred to as separate backlights for simplicity. As shown in  FIG. 9 , a total of four indicators are provided by two secondary backlight layers. Backlight layer  940  provides light to square (“stop”) indicator etch  904  and play indicator etch  906  on primary layer  902 . Backlight layer  942  provides light to pause indicator etch  908  and circle (“record”) indicator  910 . In some embodiments, four colors may be used such that each indicator is illuminated with a different color. Alternatively, two or three colors may be used. For example, light source  944  may provide either red or green light to create a red stop indicator and a green play indicator. The light source associated with layer  942  (not shown) may provide either an orange or red light to create an orange pause indicator and a red record indicator. Thus, three total colors can be used in the display system. In some embodiments, to prevent light generated from one secondary backlight to reach the indicators associated with the other secondary backlight, a second color filter layer (e.g., in addition to color filter layer  920 ) may be provided to absorb undesired colors. 
       FIG. 10A  shows another exploded view of a portion of a display system for presenting multiple identifiers at substantially the same location on the display. Rather than etching the shape of the identifier onto primary backlight layer  1002 , the shape of the identifier can be created by shaping color filters  1022  on color filter layer  1020 . In other embodiments, color filters  1022  may be part of separate color filter layers. Semitransparent region  1004  may be etched such that the region is large enough to allow all of the shapes to project through the display system. 
     A larger view of color filters  1022  is shown in  FIG. 10B . Here, color filters  1024  and  1026  may be shaped like a triangular “play” icon and a square “stop” icon, respectively. Play indicator filter  1024  and stop indicator filter  1026  may be overlaid. Play indicator filter  1024  may be tinted green, and stop indicator  1026  may be tinted red. Thus, filter  1024  may be more effective at transmitting green, and filter  1026  may be more effective at transmitting red. If green light is emitted from secondary light source  1042  of secondary backlight layer  1040 , the image projected onto the display can be a substantially green play identifier. If red light is emitted from secondary light source  1042 , the image projected onto the display may be a substantially red play identifier. If neither filter completely blocks the other color from being transmitted, overlapping portion  1028  may pass light regardless of the color. 
     Alternatively, overlapping portion  1028  may be completely removed, leaving a hole in the color filter layer, or overlapping portion  1028  may be completely transparent or translucent. Either way, the overlapping portion may pass light generated by the secondary backlight regardless of the color. The other, non-overlapping portions of the color filters, which determine the shape that is projected onto the display, may selectively pass light based on the color of the transmitted light. Thus, depending on the color of the light, a viewer may see either the play or the stop indicator on the display. 
     In accordance with another embodiment of the present invention, an icon projected onto a display may be dynamic. This type of icon may be used to show the progress of a system process, such as the progress of media download (e.g., the more dynamic, the closer the download is to complete). In some embodiments, a dynamic icon may be created by using an icon that alternates between different colors.  FIG. 10C  shows an illustrative color filter arrangement for creating such a dynamic icon. These color filters may be used in place of color filters  1022  ( FIG. 10A ). Eight or more color filter pieces may be used and divided evenly into two types. For example, color filters  1060  may pass orange light, and color filters  1062  may pass red light. The eight pieces can be circularly arranged such that adjacent pieces are different colors. Thus, if light source  1042  alternates between emitting orange and red light every half-second, the resulting indicator projected on the display may appear to be rotating. By varying the speed of the alternating light, the speed of the rotation may be varied. 
     In other embodiments, a dynamic icon may be created by turning the light source of the secondary backlight ON and OFF such that the resulting icon blinks. Then, the rate of the blink may be used as a progress indicator. In still other embodiments, the brightness of the light provided by the secondary backlight may be varied. To vary the brightness, the light source of the secondary backlight may be driven by a variable voltage source, and the intensity of the light may be adjusted by adjusting the voltage. Alternatively, the brightness may be varied by driving the light source with a pulse-width-modulation (PWM) signal and varying the duty cycle. 
     An icon that indicates the status of the electronic device may be provided using any of the embodiments described above in connections with  FIGS. 4A-10C , and, if necessary, may vary in any number of properties, such as in color, shape, brightness, blinking pattern (e.g., steady light, slow blink, fast blinking), moving indicator speed, and location. Any of the above properties may vary in time (e.g., blinking pattern may speed up or slow down), or may maintain the same properties over time. Also, a provided icon may change properties (e.g., change from a blinking pattern to constant) at any appropriate time. Thus, it should be understood that a secondary backlight may be ON even if the backlight is not providing a steady light. 
     The particular properties of light provided by a secondary backlight may also be chosen to conserve power in the electronic device. In these embodiments, a secondary backlight may selectively or intermittently provide light for an icon. For example, an indicator may be displayed for predetermined time intervals, such as for half a second every five seconds. Also, the intensity of the light, and therefore the amount of power consumed, may be lowered by using, e.g., a PWM waveform. 
       FIG. 11  shows illustrative flow diagram  1100  for changing the state of a display system from ON to OFF. At step  1102 , a primary backlight (e.g., primary backlight  306  in  FIG. 3 ) that illuminates a display (e.g., display  304  in  FIG. 3 ) may be turned OFF. The primary backlight may be turned OFF after a period of monitored user inactivity. The idle time necessary for the primary backlight to be turned OFF may be programmed by the user or may be hard-coded or hard-wired to a predetermined length of time. Alternatively, the primary backlight may be turned OFF in response to a user indication, such as by pressing a button on the electronic device (e.g., using user interface  108 ). In addition, a user may program the electronic device such that the primary backlight is always OFF. In this case, step  1102  may be skipped. 
     The display itself may be turned OFF at step  1104  in  FIG. 11 . The display may be turned OFF in response to the primary backlight turning OFF, or the display may be turned OFF at substantially the same time as the primary backlight. In other cases, the primary backlight may be turned OFF after a period of monitored user inactivity or in response to a user indication. 
     At step  1106  in  FIG. 11 , a secondary backlight (e.g., secondary backlight  308  in  FIG. 3 ) may be turned on to project a light through the primary backlight and onto the display. The light may be projected through a portion of the primary backlight, and the portion may be of any suitable size and shape. Thus, an icon of that size and shape may be displayed on the display. 
     The icon may be displayed at step  1106  at any suitable time after step  1104 . The icon may be displayed substantially immediately following step  1104  to indicate the status of the device. For example, if the electronic device is playing music at the time the display is turned OFF, the secondary backlight may turn ON to display a “play” icon to the user substantially immediately following step  1104 . Alternatively, secondary backlight may be turned ON at some point substantially after step  1104  to indicate a change in the status of the device. For example, if media is downloading to the electronic device (e.g., into storage device  104 ) when the display is turned OFF, secondary backlight may turn ON after the download is complete to notify the user. The secondary backlight may also turn ON to indicate a change in device conditions, such as to indicate a low battery. 
     It should be understood that  FIG. 11  is merely illustrative. In fact, steps  1102 ,  1104 , and  1106  may be performed in any order or at substantially the same time. Furthermore, any of the shown steps may be omitted or modified, and any additional steps may be performed without leaving the scope of the invention. For example, in some embodiments, one or both of the primary backlight and the display may remain ON when the secondary backlight is ON. This may be used to provide information on the display other than media provided by the display. For example, the secondary backlight may be used to tint an area of the display a different color in order to highlight or emphasize that area of the screen. 
       FIG. 12  shows illustrative flow diagram  1200  for responding to a user input when a display (e.g., display  304  of  FIG. 3 ) is OFF. At step  1202 , a user input is received. The user input may be a push of a button on the electronic device or any other suitable user input (e.g., rotation of the device). In response to the user input, a determination is made as to whether to turn the display ON at step  1204 . Determination  1204  may be based on user preferences, particular device conditions, such as the remaining battery life of the device, or device operating conditions, such as the length of time the display has been OFF. 
     If the display is to be turned ON, the secondary backlight, if ON, may be turned OFF at step  1206 . The display may be turned ON at step  1208 , and the content provided by the display may depend on the particular user input received at step  1202 . To illuminate the display, a primary backlight may additionally be turned ON at step  1210 . Alternatively, depending on user preference, remaining battery life, or any other suitable reason, the primary backlight may remain OFF. 
     If the display is to remain OFF following the user input, the state of the secondary backlight may change at step  1212  if the status of the electronic device changes. For example, the status of the electronic device may change in response to receiving the user input at step  1202 . In response to the user input or in response to a change in device status caused by the user input, the secondary backlight may turn ON, turn OFF, change color, or change the properties of the light it provides in some other way. Each possible device status may be associated with a status indicator with particular properties. A media player, for instance, may take on “play,” “pause,” “stop,” and “record” states, and each state may be associated with an indicator of different color, brightness, etc. Thus, if a user input is received at step  1202  that changes the electronic device from one state to another, the properties of the light provided by the secondary backlight may change accordingly. In particular, the electronic device may determine the status of the device and may determine what properties of light to provide, if any, based on the determined status. The particular properties of an icon for each device status may be programmed by the user. For example, a user may set preferences for the appearance of the icon into a menu provided by the electronic device (e.g., using user interface  108  of  FIG. 1 ). Alternatively, the particular properties of an icon may be hard-coded or hard-wired into the device (e.g., a “play” icon may be hard-wired to be green), or the properties may be determined by a combination of user-defined preferences and hard-wired or hard-coded states. 
     It should be understood that  FIG. 12  is merely illustrative. Any of the steps in  FIG. 12  may be omitted, modified, or rearranged, and any additional steps may be performed without leaving the scope of the invention. Furthermore, flow diagram  1200  may be modified to include multiple secondary backlights, if applicable. 
       FIG. 13  shows exemplary steps that can be implemented in step  1212 . At step  1302 , the type of user input received at step  1202  is determined. The secondary backlight may provide a green light or a red light depending on the determination. If a “pause” command is received at step  1202 , the secondary backlight may turn on a red light at step  1304 . All other secondary backlight sources may be turned OFF. The red light may project a red pause icon onto the display (such as that shown in  FIG. 7 ). 
     If the user input received at step  1202  in  FIG. 13  is a “play” command, the secondary backlight may turn on a green light at step  1306 . All other secondary backlight sources may be turned OFF. The green light may project a green play icon onto the display, (such as indicator  206  shown on display screen  202  in  FIG. 2B ). The icon may be projected through a portion of the primary backlight. 
       FIG. 14  shows illustrative flow diagram  1400  for changing the properties of light provided by a secondary backlight when the secondary backlight may be ON. Flow diagram  1400  may be used, for example, as part of step  1106  in flow diagram  1100  ( FIG. 11 ) or in conjunction with step  1212  in flow diagram  1200  ( FIG. 12 ). At step  1402 , the electronic device may wait for a change in status. For example, the electronic device may detect a state change from “play” to “stop,” or the electronic device may detect that a download has completed. Alternatively, the electronic device may detect a change in device conditions or in other device operating conditions. To detect a change, interrupt circuitry may be implemented in the electronic device, or the electronic device may periodically poll (e.g., every 5 ms) for the current state of the device. 
     After a change in the status has been detected, the electronic device may determine properties associated with the new state of the device at step  1404 . As discussed above, some operating states of a device can be associated with display identifiers of different shape, color, or other properties, and these properties may be predefined by a user, hard-wired or hard-coded, or set according to a combination of user preferences and default device settings. Light of these particular properties may be provided by a secondary backlight. Thus, at step  1404 , the particular properties of light that is to be provided by a secondary backlight is determined. 
     After determining the light properties associated with the new state of the electronic device, at step  1406 , the light provided by the secondary backlight may change to reflect the determined properties. For example, the secondary backlight may change from providing a green light to providing a red light if the status of the devices changes from “play” to “pause.” In some cases, certain states may not be associated with any identifier. For example, an electronic device may not display an indicator when in a “pause” state. Therefore, the secondary backlight may be turned OFF at step  1406  if the electronic device changes from a “play” to a “pause” state. Afterwards, the electronic device may return to step  1402  to detect when another status change occurs. Thus, if the electronic device returns to a “play” state, the secondary backlight may be turned ON again. 
     It should be understood that  FIG. 14  is merely illustrative. Any of the steps in  FIG. 14  may be omitted, modified, or rearranged, and any additional steps may be performed without leaving the scope of the invention. Furthermore, flow diagram  1400  may be modified to include multiple secondary backlights, if applicable. 
     Thus, the foregoing describes system and methods for providing one or more icons on a display regardless of whether the display is ON. Those skilled in the art will appreciate that the invention can be practiced by other than the described embodiments, which are presented for the purpose of illustration rather than of limitation.

Metadata:
Filing Date: 20070518
Publication Date: 20121023
Grant Date: 20121023
Priority Date: 20070518
Inventors: ROSENBLATT MICHAEL
Assignee: APPLE INC
CPC Classifications: [{"code": "G09G3/2003", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y02D10/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2330/021", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02F1/1336", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/3265", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/3265", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G3/3406", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G3/2003", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3406", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F2201/16", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02F1/1336", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02F2201/16", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2330/021", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 40026992