PATENT DOCUMENT

Publication Number: US-9788392-B2
Application Number: US-201514636004-A
Country: US
Kind Code: B2

Title: Computer light adjustment

Abstract:
A computing device is disclosed. The computing device includes a light source configured to output light. The computing device also includes a light sensor configured to measure the level of light surrounding the computing device. The computing device further includes a control mechanism operatively coupled to the light source and light sensor and configured to adjust the level of output light based on the measured level of light surrounding the computing device.

Claims:
What is claimed is: 
     
       1. A handheld electronic device, comprising:
 a light source; 
 a light sensor; 
 a light controller configured to process light information associated with the light sensor and the light source; 
 a housing that encloses the light source, the light sensor, and the light controller, wherein the housing includes an opening and wherein the light sensor directly overlaps the opening and is configured to detect light through the opening; and 
 an output device that conveys signals to a user through the opening. 
 
     
     
       2. The handheld electronic device defined in  claim 1  wherein the light source comprises a portion of a display. 
     
     
       3. The handheld electronic device defined in  claim 2  wherein the display comprises a liquid crystal display. 
     
     
       4. The handheld electronic device defined in  claim 1  wherein the light sensor comprises an ambient light sensor. 
     
     
       5. The handheld electronic device defined in  claim 4  further comprising a light guide configured to focus ambient light onto the ambient light sensor. 
     
     
       6. The handheld electronic device defined in  claim 1  wherein the output device comprises a speaker and the opening comprises a hole in a speaker grill over the speaker. 
     
     
       7. The handheld electronic device defined in  claim 1  wherein an intensity of the light source is adjusted based on data gathered by the light sensor. 
     
     
       8. An electronic device, comprising:
 a light source; 
 an ambient light sensor; 
 a housing in which the light source and the ambient light sensor are mounted, wherein the housing includes a speaker opening and wherein the ambient light sensor receives ambient light through the speaker opening; and 
 a processor that provides control signals to the light source based on ambient light measurements from the ambient light sensor. 
 
     
     
       9. The electronic device defined in  claim 8  wherein the light source comprises a status indicator. 
     
     
       10. The electronic device defined in  claim 8  wherein the light source comprises a light source associated with a display. 
     
     
       11. The electronic device defined in  claim 8  further comprising a light guide that distributes ambient light to the ambient light sensor. 
     
     
       12. The electronic device defined in  claim 8  wherein the ambient light sensor directly overlaps the speaker opening. 
     
     
       13. The electronic device defined in  claim 8  wherein the light source comprises a light emitting diode. 
     
     
       14. An electronic device, comprising:
 a processor; 
 a light source; 
 a light sensor; 
 a housing in which the processor, the light source, and the light sensor are mounted, wherein the housing includes an opening and wherein the light sensor is configured to detect light through the opening; and 
 an electronic component that transmits signals through the opening, wherein the opening directly overlaps the light sensor. 
 
     
     
       15. The electronic device defined in  claim 14  wherein the processor controls a brightness of the light source based on a measured output from the light sensor. 
     
     
       16. The electronic device defined in  claim 14  wherein the light source provides backlight for a keyboard. 
     
     
       17. The electronic device defined in  claim 16  wherein the light source comprises a plurality of optical fibers. 
     
     
       18. The electronic device defined in  claim 16  wherein the keyboard comprises keys and wherein the light source illuminates an area around each of the keys. 
     
     
       19. The electronic device defined in  claim 16  wherein the keyboard comprises keys and wherein the light source provides illumination through each of keys. 
     
     
       20. The electronic device defined in  claim 19  further comprising a mask layer positioned between the keyboard and the light source, wherein the mask layer has openings through which light is transmitted.

Description:
This application is a continuation of U.S. patent application Ser. No. 13/946,534, filed Jul. 19, 2013, which is a continuation of U.S. patent application Ser. No. 12/949,563, filed Nov. 18, 2010, now U.S. Pat. No. 8,531,386, which is a continuation of U.S. patent application Ser. No. 11/737,121, filed Apr. 18, 2007, now U.S. Pat. No. 7,839,379, which is a continuation of U.S. patent application Ser. No. 10/402,311, filed Mar. 26, 2003, now U.S. Pat. No. 7,236,154, which claims priority to U.S. Provisional Patent Application No. 60/436,205, filed Dec. 24, 2002, all of which are hereby incorporated herein in their entireties. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to computing devices and/or systems. More particularly, the present invention relates to improved features for controlling light associated with the computing devices and/or systems. 
     DESCRIPTION OF THE RELATED ART 
     Portable computing devices such as notebook computers generally consist of a lid and a base, each of which carries various components used to operate the notebook computer. By way of example, the base may include a hard drive, a modem, a processor, a disk drive, memory, a keyboard, a track pad, buttons and the like, and the lid may include a display such as a liquid crystal display (LCD). The base may also include a battery for supplying power to the components of the notebook computer. The battery is often quite small and therefore generally only has enough power to keep the notebook computer running for a few hours. As should be appreciated, in order to operate effectively, each component consumes some of the power thereby reducing the life of the battery. One of the biggest consumers of power is the display. 
     Displays are configured to give visual feedback to a user. For example, the displays may display textual or graphical information such as graphical user interface (GUI). Displays typically include controls that allow a user to adjust characteristics of the display screen such as brightness. By way of example, the controls may be implemented through keys disposed on a keyboard. The user typically adjusts the brightness by incrementally or continuously holding down the key. The controls may also be implemented through buttons or switches located on the outside of the notebook computer. Some external displays such as those utilizing cathode ray tubes (CRT), as for example televisions and computer monitors, may also include controls that allow a user to adjust contrast. Moreover, some televisions include control mechanisms that automatically adjust the brightness level of the television according to the ambient light around the television. 
     Notebook computers also give visual feedback to users via small indicators positioned on the notebook computer. By way of example, some indicators use light to indicate that a notebook computer is turned on/off or that the notebook computer is in a sleep mode. External lights may be used in some cases to provide light to the keyboard of the notebook computer so that the keys may be seen in low light conditions. 
     Although light devices of notebook computers typically work well, there are continuing efforts to improve their form, feel and functionality. For example, it may be desirable to control the light devices of a notebook computer according to the surroundings and environment in which they are used. 
     SUMMARY OF THE INVENTION 
     The invention relates, in one embodiment, to a computer system. The system includes a processor configured to execute instructions and to carry out operations associated with the computer system. The computing device also includes an input/output controller operatively coupled to the processor and configured to control interactions with one or more input/output devices that are coupled to the computer system, one or more light sources configured to emit light around the computer system, a light controller operatively coupled to the processor and configured to process light information associated with the one or more light sensors and the one or more light sources, a display device configured to display text and graphics; a display controller operatively coupled to the processor and configured to process display commands to produce text and graphics on the display device, and a program storage block operatively coupled to the processor and configured to store data being used by the computer system, the program storage block storing an illumination program for controlling how the one or more light sources are illuminated, the illumination program containing illumination profiles for each of the light sources of the computing system, the illumination profiles describing the relationship between the light output of the one or more light sources and the measured ambient light level, the illumination profiles being accessed through a light control menu, which is viewed on the display device as part of a graphical user interface. By way of example, the computing device may correspond to a portable computing device such as a notebook computer. 
     The invention relates, in another embodiment, to a computing device. The computer device includes, at least, a first light source capable of outputting light in order to illuminate a first component of the computing device, a second light source capable of outputting light in order to illuminate a second component of the computing device, the second component being distinct from the first component, a light sensor configured to measure the level of light surrounding the computing device; and a control mechanism operatively coupled to the first and second light sources and the light sensor and configured to adjust the level of out put light from the first and second light sources based on the measured level of light surrounding the computing device and first and second illumination profiles associated with the first and second light sources, the first illumination profile being different than the second illumination profile. 
     The invention relates, in yet another embodiment, to a method of illuminating multiple light sources associated with a notebook computer. The method is includes at least the following steps: determining the ambient light level, automatically adjusting the light intensity of a first light source of a first component of the notebook computer based on the ambient light level, automatically adjusting the light intensity of a second light source of a second component of the notebook computer based on the ambient light level, storing a first illumination profile for the first light source, the first illumination profile defining a relationship between ambient light levels and the light intensity of the first light source, and storing a second illumination profile for the second light source, the second illumination profile defining a relationship between the ambient light level and the light intensity of the second light source, the second illumination profile being different than the first illumination profile. In the described embodiment, the light intensity of the first light source is adjusted according to the first illumination profile and wherein the light intensity of the second light source is adjusted according to the second illumination profile. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which: 
         FIG. 1  is a block diagram of a computing device, in accordance with one embodiment of the present invention. 
         FIG. 2  is graphical representation showing light intensity versus ambient light level, in accordance with several embodiments of the present invention. 
         FIG. 3  is a block diagram of a computer system, in accordance with one embodiment of the present invention. 
         FIG. 4  is a flow diagram of illumination processing, in accordance with one embodiment of the present invention. 
         FIG. 5  is a diagram of a graphical user interface (GUI), in accordance with one embodiment of the present invention. 
         FIGS. 6A-C  are graphical representations showing light intensity versus ambient light level, in accordance with several embodiments of the present invention. 
         FIG. 7  is a perspective diagram of a portable computer, in accordance with one embodiment of the invention. 
         FIG. 8  is a side elevation view, in cross section, of a portable computer, in accordance with one embodiment of the present invention. 
         FIG. 9  is a side elevation view, in cross section, of a portable computer, in accordance with an alternate embodiment of the present invention. 
         FIG. 10  is a side elevation view, in cross section, of a portable computer, in accordance with an alternate embodiment of the present invention. 
         FIG. 11  is a side elevation view, in cross section, of a portable computer, in accordance with an alternate embodiment of the present invention. 
         FIG. 12  is a side elevation view, in cross section, of a portable computer, in accordance with an alternate embodiment of the present invention. 
         FIG. 13  is a side elevation view, in cross section, of a back lit keyboard, in accordance with one embodiment of the present invention. 
         FIG. 14  is an exploded perspective view of a back lit keyboard, in accordance with one embodiment of the present invention. 
         FIG. 15  is a broken away side elevation view, in cross section, of a back lit keyboard, in accordance with one embodiment of the present invention. 
         FIG. 16  is a top view, in cross section, of a portable computer, in accordance with one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The invention generally pertains to controlling light sources associated with various components of a computing device or system. In particular, controlling the intensity of light outputted by the light sources based on the level of ambient light surrounding the computing device or system. One aspect of the invention relates to automatically adjusting a light source associated with a display device according to the ambient light level. As should be appreciated, in order for the display to be seen properly, the light therefrom generally has to be bright in high ambient light and relatively dim in low ambient light (e.g., darkness). Another aspect of the invention relates to automatically adjusting a light source associated with a keyboard according to the ambient light level. As should be appreciated, in order for the keyboard to be seen properly, the light therefrom generally has to be bright in low ambient light. In one particular embodiment, the keyboard light comes on in low ambient light thereafter adjusts to the ambient light level and then automatically shuts off in brighter ambient light. Yet another aspect of the invention relates to automatically adjusting a light source associated with an indicator according to the ambient light level. 
     The invention is particular suitable for use in portable computers such as notebook or laptop computers where substantial battery life can be saved by adjusting the intensity of light in order to reduce the power consumption of the light sources. The amount saved generally depends on the ambient light level. By way of example, the life of the battery may be increased up to 40% when automatically adjusting the light sources described above. In addition, the invention provides light in a controlled manner so that components of the portable computer can be seen properly and clearly. For example, the light may illuminate a component such as a keyboard so that it can be used in low light conditions (e.g., in the dark). 
     Embodiments of the invention are discussed below with reference to  FIGS. 1-16 . However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes as the invention extends beyond these limited embodiments. 
       FIG. 1  is a block diagram of a computing device  100 , in accordance with one embodiment of the present invention. The computing device  100  is generally configured to process, send, retrieve and/or store data. By way of example, the computing device may correspond to desktop computers (both segmented and all-in-one machines), portable computers (e.g., laptops), handhelds (e.g., media players, personal digital assistants and mobile phones) or the like. As shown, the computing device  100  includes a light source  102  and a light sensor  104 , both of which are operatively coupled to a control mechanism  106 . The light source  102 , light sensor  104  and control mechanism  106  make up a light adjustment circuit that is configured to effect lighting associated with the computing device  100  in a non-trivial manner. 
     The light source  102  is generally configured to output light  108  so that it can be seen by a user of the computing device  100 . For example, the light source  102  may be used to light up many types of light devices such as indicators, displays, keyboards, buttons, connectors and the like. With regards to indicators, keyboards buttons, and connectors the light source may correspond to a light emitting diode (LED). With regards to the display, the light source may correspond to a display tube (e.g., cathode ray tube) or a display panel such as those used in liquid crystal displays (LCD). The light sensor  104 , on the other hand, is configured to receive and measure the level of light  110  that surrounds the computing device  100  during use, as for example, light that is produced by incandescent, sunlight, fluorescents, and the like. This type of light is sometimes referred to as “ambient light.” By way of example, the light sensor  104  may correspond to a photodiode, phototransistor, photoresistor or the like. An example of an illuminated connector may be found in U.S. Pat. No. 6,357,887, titled “Housing for a Computing Device”, issued Mar. 19, 2002, which is herein incorporated by reference. 
     Moreover, the control mechanism  106  is generally configured to adjust the level of the light  108  based on the measured level of the light  110 . For example, depending on the light level of light  110 , the control mechanism  106  may increase or reduce the power that is delivered to the light source  102  thereby effecting the light intensity of the light source  102 . The intensity of the outputted light  108  is generally set at a level that differentiates it from the ambient light  110 , i.e., provide sufficient contrast between the light being outputted by the light source  102  and the ambient light surrounding the computing device  100 . In one particular embodiment, and referring to  FIG. 2 , the intensity of the outputted light  108  is configured to be high in high ambient light  110  and low in low ambient light  110 . This is typically done so as to allow a user to easily view the outputted light  108  when using the computing device  100 , i.e., more light is needed when the ambient light level is bright and not as much light is needed when the ambient light level is dark. This is also done to reduce the power consumption of the computing device  100  (as some users may leave light devices, i.e., displays, on maximum brightness). This may be advantageous in portable devices that include batteries, i.e., reducing the power consumption may increase battery life. Although this particular embodiment is shown and described, it should be noted that it is not a limitation and that the relationship between light intensity and ambient light level may vary according to the specific needs of each device. For example, in some cases, the intensity of the outputted light may be configured to be low in high ambient light  110  and high in low ambient light  110  (e.g., this may allow the light to be seen in darkness). By way of example, the ambient light level may range from about 0 lux (e.g., darkness) to about 1000 lux (e.g., a very bright room). 
     The control mechanism  106  may be a dedicated block or it may be a part of the control system that controls other functions of the computing device  100 . By way of example, it may correspond to a micro controller and/or a processor. 
       FIG. 3  is a block diagram of a computer system  150 , in accordance with one embodiment of the present invention. By way of example, the computer system  150  may correspond to the computing device  100  shown in  FIG. 1 . The computer system  150  generally includes a processor  152  (e.g., CPU or microprocessor) configured to execute instructions and to carry out operations associated with the computer system  150 . For example, using instructions retrieved for example from memory, the processor may control the reception and manipulation of input and output data between components of the computer system  150 . In most cases, the processor  152  executes instruction under the control of an operating system or other software. The processor can be a single-chip processor or can be implemented with multiple components. 
     The computer system  150  also includes an input/output (I/O) controller  154  that is operatively coupled to the processor  152 . The (I/O) controller  154  may be integrated with the processor  152  or it may be a separate component as shown. The I/O controller  154  is generally configured to control interactions with one or more I/O devices  156  that can be coupled to the computer system  150 . The I/O controller  154  generally operates by exchanging data between the computer system  154  and I/O devices  156  that desire to communicate with the computer system  150 . In some cases, the I/O devices  156  may be connected to the I/O controller  154  through wired connections such as through wires or cables. In other cases, the I/O devices  156  may be connected to the I/O controller  154  through wireless connections. By way of example, the I/O devices  156  may be internal or external devices such as hard drives, disk drives (e.g., floppy, CD, DVD, etc.), keyboards, mice, track balls, touch pads, printers, scanners, speakers, video cameras, MP3 players and the like. The I/O devices  156  may also be network-related devices such as network cards or modems. In the illustrated embodiment, the I/O device  156  is an illuminable keyboard, as for example, a backlit keyboard. 
     The computer system  150  also includes a light controller  162  that is operatively coupled to the processor  152 . The light controller  162  may be integrated with the processor  152  or it may be a separate component as shown. The light controller  162  is configured to process light information associated with one or more light sensors  164  and one or more light sources  166 . The light sensors  164  are generally configured to measure the ambient light level surrounding the computer system  150  and the light sources  166  are generally configured to emit light. By way of example, the light sensor may be configured to measure the ambient light level between about 0 lux (e.g., darkness) to about 1000 lux (e.g., a very bright room). In most cases, the light controller  162  operates by exchanging data between the light sensors  164 , light sources  166  and the processor  152 , i.e., the light controller  162  directs the measured output from the light sensors to the processor  152  and it directs light instructions from the processor  152  to the one or more light sources  166 . In the illustrated embodiment, the computer system includes a pair of the light sensors  164 . It is generally believed that using multiple light sensors produces a more accurate reading of the ambient light surrounding the computer system (e.g., average). It should be noted that two light sensors is not a limitation and that one or more light sensors may be used. 
     The light sources may be widely varied. By way of example, the light sources may be one or more light emitting diodes (LED), light emitting semiconductor dies, lasers, incandescent light bulbs, fluorescent light bulbs, neon tubes, liquid crystal displays (LCD), and the like. Furthermore, the location of the light sources may be widely varied. The light sources may be located in almost any component of the computer system  150 . For example, the light sources may be contained in one or more of the I/O devices described above or within a housing of the computer system  150 , as for example, the housing that contains the processor  152 . In the illustrated embodiment, a first light source  166 A emits light for lighting up the keyboard  156 , and a second light source  166 B emits light for lighting up an indicator  157  of the computer system  150 . By way of example, the indicator  157  may be a sleep indicator that alerts users when the computer system is in a sleep mode. In most cases, the light sources  166 A and  166 B correspond to LEDs. 
     The computer system  150  also includes a display controller  168  that is operatively coupled to the processor  152 . The display controller  168  may be integrated with the processor  152  or it may be a separate component as shown. The display controller  168  is configured to process display commands to produce text and graphics on a display device  170 . By way of example, the display device  170  may be a monochrome display, color graphics adapter (CGA) display, enhanced graphics adapter (EGA) display, variable-graphics-array (VGA) display, super VGA display, liquid crystal display (e.g., active matrix, passive matrix and the like), cathode ray tube (CRT), plasma displays and the like. In the illustrated embodiment, the display device corresponds to a liquid crystal display (LCD) that contains a light source  172  for delivering light to the LCD. In most cases, the light source  172  corresponds to a light panel such as a fluorescent light panel that emits light behind (and sometimes beside) the remaining layers or panels of the LCD (e.g., polarizing filters, liquid crystal cells, color filters, glass plate). 
     Although not shown, the computer system  150  may include one or more media bays (expansion bays) may be used to receive media bay devices (expansion bay devices) to provide greater resources to the computer system  150 . As examples, the types of devices include a floppy drive, a hard drive, a CD-ROM drive, a DVD drive, or a battery. The media bays are typically externally accessible from to the computer system  150  so that media bay devices can be easily be inserted into the media bays or removed from the media bays. The removability of the media bay devices allows a few media bays to support a variety of different types of devices in a flexible manner. 
     In most cases, the processor  152  together with an operating system operates to execute computer code and produce and use data. The computer code and data may reside within a program storage block  176  that is operatively coupled to the processor  152 . Program storage block  176  generally provides a place to hold data that is being used by the computer system  150 . By way of example, the program storage block may include Read-Only Memory (ROM), Random-Access Memory (RAM), hard disk drive and/or the like. The computer code and data could also reside on a removable program medium and loaded or installed onto the computer system when needed. Removable program mediums include, for example, CD-ROM, PC-CARD, floppy disk, magnetic tape, and a network component. As is generally well known, RAM is used by the processor as a general storage area and as scratch-pad memory, and can also be used to store input data and processed data. ROM can be used to store instructions or program code followed by the processor as well as other data. Floppy and hard disk drives can be used to store various types of data. Floppy disk drive facilitates transporting such data to other computer systems, and hard disk drives permit fast access to large amounts of stored data. 
     In one embodiment, program storage block  176  is configured to store an illumination program for controlling how the lights sources, as for example, the light sources associated with the keyboard  156 , indicator  157  and the display device  170 , are illuminated. The illumination program may contain illumination profiles for each of the light sources in the computer system  150 , as for example light sources  166 A,  166 B and  172 . The illumination profiles generally contain information or tables that describe how the light sources change in accordance with some event. For example, the illumination profiles may describe the relationship between the light output and the ambient light level, i.e., for a measured ambient light level, the light intensity of the light source should be set at a particular level. This information may be used in the illumination program to control the light sources based on a particular level of ambient light. The ambient light level may be the measured light level as for example, the level measured by the light sensors  164  or it may be some preset value. With regards to the later, the preset value may be some default value based on avenges or it may be a value corresponding to a particular use, i.e., the user may set the value based on his/her location (e.g., lots of sunshine, inside a room using fluorescents and/or incandescent, complete or partial darkness, and the like). 
     In one implementation, the illumination profiles may be accessed by a user through a light control menu, which may be viewed on the display device  170  as part of a GUI interface. The light control menu may include light control settings pertaining to the illumination profiles. In fact, the light control menu may serve as a control panel for reviewing and/or customizing the light control settings, i.e., the user may quickly and conveniently review the light control settings and make changes thereto. Once changed, the modified light control settings will be automatically saved and thereby employed to handle future illumination processing. 
       FIG. 4  is a flow diagram of illumination processing  200 , in accordance with one embodiment of the present invention. By way of example, illumination processing may be implemented in the computer system of  FIG. 2 . Illumination processing generally begins at block  202  where a determination is made as to whether or not a light feature associated with a light source is activated. The light feature is generally concerned with how the various light sources of a computer system, as for example, the keyboard lights  166 A, the indicator lights  166 B and the display device  172  of  FIG. 2 , are illuminated. If the light feature is not activated, then the process flow ends. 
     If the light feature is activated, then the process flow proceeds to block  204  where the ambient light level is determined. The ambient light level is an indication of the degree of light to be utilized with illumination processing. In one embodiment, the ambient light level is determined by monitoring the output from one or more light sensors, as for example light sensors  164  in  FIG. 2 . In another embodiment, the ambient light level is determined by referring to user settings. For example, a user may enter information about the ambient light level (e.g., working inside, working outside, working in a dark room, working in a well lit room, etc.). The information may be initiated at start up by the computer system, as for example via a pop up window, or it may be user initiated via a GUI window that is opened by the user. 
     Following block  204 , the process flow proceeds to block  206  where the light intensity of the light source is determined based on the ambient light level. This may be accomplished with a formula, a data table or the like. For example, the light intensity may be calculated using a formula, which includes the ambient light level as a variable. Additionally, the light intensity may be determined using data tables that show a relationship between the ambient light level and the intensity of the outputted light, i.e., once the ambient light level is determined, it can be used to look up the appropriate light intensity associated therewith. The data tables may be found experimentally or through simulation or modeling. The formulas and data tables themselves may be widely varied. For example, they may be preset or they may be modifiable. 
     Following block  206 , the process flow proceeds to block  208  where the light intensity of the light source is set. For example, the power delivered to the light source may be adjusted to bring it the appropriate light intensity. After the light intensity has been set, the illumination processing is complete and ends. However, the illumination processing may be repeated at various intervals in case some input has changed, i.e., check to see if the light feature is still activated or if the data tables have been modified. By way of example, illumination processing may be repeated about 10 times a second, once every two seconds or somewhere therebetween. 
     The various aspects of the illumination processing described above can be used alone or in various combinations. The illumination processing is preferably implemented by a combination of hardware and software, but can also be implemented in hardware or software. The illumination processing can also be embodied as computer readable code on a computer readable medium. The computer readable medium is any data storage device that can store data, which can thereafter be read by a computer system. Examples of the computer readable medium include read-only memory, random-access memory, CD-ROMs, DVDs, magnetic tape, optical data storage devices, and carrier waves. The computer readable medium can also be distributed over a network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. 
       FIG. 5  is a diagram of a graphical user interface  250  (GUI), in accordance with one embodiment of the present invention. The GUI  250  represents the visual display panel for displaying the light profiles of one or more light sources on a computer display screen. Through the GUI  250 , the user may quickly and conveniently review the light settings associated with the light source(s) and make changes thereto. The GUI  250  serves as a control panel for reviewing and/or customizing the light options associated with the various light sources. 
     As shown, the GUI  250  includes a window frame  252  that defines a window or field  254  having contents contained therein. The contents may be widely varied. The contents may include one or more on screen options, switches, labels, warnings and the like. In the illustrated embodiment, the GUI is dedicated to keyboard illumination and thus the field  254  includes an illumination option  256 , a light adjustment slider  258 , and an ambient light adjustment option  260 . The illumination option  256 , if it is enabled, instructs a computer system to illuminate the light source when the ambient light level is low. (Sometimes the keyboard does not have to be lit). The light adjustment slider  258 , on the other hand, gives the user the ability to designate the desired brightness of the illumination provided by the light source. For example, by moving the slider, the user may increase or decrease the level of brightness. Furthermore, the ambient light adjustment option  260 , if it is enabled, allows the computer system to automatically adjust the light intensity of the light source based on the ambient light levels. Additionally, a visual indication such as warning window  262  or check mark  264  may be used to inform the user as to which options are selected. 
     It should be noted that the GUI configuration shown in  FIG. 5  is not a limitation and that the configuration may vary according to the specific needs of each light source. For example, each light source may have different light requirements (e.g., colors, durations, etc.) and therefore the GUI may need to be modified. 
       FIGS. 6A and 6B  are light distribution plots  300  and  302 , respectively, that may be used to control the light intensity of a light source associated with a component of a computer system, in accordance with one embodiment of the invention. By way of example, the light distribution plots  300  and  302  may correspond to the data tables or formulas described in  FIG. 3 . In  FIG. 6A , the light distribution plot  300  is used to control the light intensity of a light source associated with a keyboard. In  FIG. 6B , the light distribution plot  302  is used to control the light intensity of a light source associated with a display (LCD). In both Figures, the light distribution plots  300  and  302  illustrate curves  304  showing light intensity as a function of ambient light level. The light intensity is on the vertical axis and ambient light level is on the horizontal axis. Referring first to the vertical axis, each of the curves  304  starts at a minimum light intensity  306  (shown by the dotted line) or greater and extends to a maximum light intensity  308 . The minimum light intensity  306  generally corresponds to the minimum amount of light needed for viewing and the maximum light intensity  308  generally corresponds to the maximum amount of light that may be produced. 
     In a similar manner and referring to the horizontal axis, each of the curves  304  also starts at a minimum ambient light level  310  or greater and extends to a maximum ambient light level  312 . The minimum ambient light level  310  generally corresponds to complete darkness. The maximum ambient light level  312 , on the other hand, may correspond to many things including the saturation point of the light sensors or the point where light is needed for viewing. For example, in  FIG. 6A , the maximum ambient light level  312  may correspond to the point where backlighting is needed to help a user view the keys of the keyboard, i.e., when the ambient light gets low (darker). By way of example, the maximum ambient light level for backlighting may be between 0 and 10 lux, and more particularly about 5 to about 10 lux. In order to prevent the backlighting from going on and off at a particular ambient level, a hysteresis loop  314  may be provided. The hysteresis loop  314  includes an activation point  316  and a deactivation point  318 . The deactivation point  318  represents the point where the backlighting is turned off and the activation point  316  represents the point where the backlighting is turned on. In  FIG. 6B , the maximum ambient light level  312  may correspond to the saturation point of the light sensors, i.e., at its capacity. By way of example, the maximum ambient light level for the display may be about 1000 lux. When each of the curves reaches this point they level off and maintain a constant light intensity even if the ambient light level is higher. 
     Referring back to both Figures, each curve  304  represents a different level of brightness. In most cases, a default curve  304 ′ (shown in bold) is present somewhere in between the other curves. The default curve  304  represents the most likely curve for all conditions and users. The curves  304 A located above the default curve  304  represent higher brightness levels to varying degrees and the curves  304 B below the default curve  304  represent lower brightness values to varying degrees. For ease of discussion, the different curves vary from 0 to +3 and from 0 to −4 brightness units in increments of 1. This, however, is not a requirement since the levels may extend to a greater number of positive or negative values. In most cases, the level of brightness is chosen by a user as for example using the GUI interface shown in  FIG. 5 . For example, a user may desire a greater amount of brightness thereby selecting the curves labeled +1, +2, or +3 or a user may desire a lesser amount of brightness thereby selecting the curves labeled −1, −2, −3 or −4. 
       FIG. 6C  is a light distribution plot  330  that may be used to control the light intensity of a light source associated with a sleep indicator, in accordance with one embodiment of the invention. By way of example, the light distribution plot  330  may correspond to the data tables or formulas described in  FIG. 3 . The light distribution plot  330  illustrates curves  332  showing light intensity as a function of time for varying levels of ambient light. The light intensity is on the vertical axis and the time is on the horizontal axis. As shown, the curves  332  follow a somewhat repeating waveform with peaks and troughs. As should be appreciated, the light intensity of sleep indicators is generally designed to fade in and out between a minimum and maximum value so as to indicate that the computer system is in a sleep mode. Each curve  332  represents a different level of ambient light. For ease of discussion, only three curves are shown (although many more curves can be used in actual practice). A first curve  332 A is configured to represent a high ambient light level, a second curve  332 B is configured to represent an average ambient light level, and a third curve  332 C is configured to represent a low ambient light level. By way of example, the low ambient light level may correspond to about 0 to about 10 lux, the high ambient light level may correspond to about 1000 lux, and the average ambient light level is somewhere in between these two values. 
     With regards to  FIGS. 6A-C , the curves themselves may be widely varied. For example, the slopes may be smaller or greater than shown. Furthermore, the curves may be curvilinear rather than rectilinear as shown. Moreover, it should be noted that maximum and minimum values, i.e., when the intensity is high or low or when the ambient light level is high and low, tend to vary according to the specific conditions in which the lights are used. For example, what is considered low ambient light with regards to the display may be different than what is considered low ambient light with regards to the indicator or keyboard (or vice versa). 
       FIG. 7  is a perspective diagram of a notebook computer  350 , in accordance with one embodiment of the invention. By way of example, the notebook computer may correspond to the Powerbook manufactured by Apple Inc. of Cupertino, Calif. The notebook computer  350  generally includes a base  352  and a lid  354 , each of which has a housing that contains various internal components. With regards to the base  352 , the internal components may correspond to various integrated circuit chips and other circuitry that provide computing operations for the notebook computer  350 . By way of example, the integrated circuit chips and other circuitry may include processors, controllers, bridges, memory, circuit boards and the like. The internal components can also take on other forms as for example hard drives, fans, batteries, and the like. The base  352  may also include various I/O devices as for example a back lit keyboard  356 , track pad  358 , disk drive  360 , speakers  362  and the like. The keyboard may be a removable keyboard such as the keyboard described in U.S. Pat. No. 6,212,066, titled, “PORTABLE COMPUTER WITH REMOVABLE KEYBOARD,” issued Apr. 3, 2001, or U.S. patent application Ser. No. 09/755,625, titled, “KEYBOARD ARRANGEMENT,” filed Jan. 4, 2001 and that has issued as U.S. Pat. No. 6,510,048, both of which are herein incorporated by reference. The base  352  may also include other circuitry including connectors  364 , buttons  366 , and indicators  368 . The lid  354 , on the other hand, typically contains a liquid crystal display (LCD)  370 . 
     In most cases, the lid  354  is pivotally coupled to the base  352  via a hinge mechanism  372 . As such, the lid  354  may rotate into an open position (as shown) or a closed position (not shown) relative to the base  352 . As should be appreciated, the LCD display  370  is visible to a user of the notebook computer  350  when the lid  354  is in the open position and no longer visible to the user when the lid  354  is in a closed position. The notebook computer  350  may include a locking mechanism  374  for securing the lid  354  to the base  352  when the lid  354  is in the closed position. The locking mechanism  374  generally consists of two parts, a base side locking mechanism  374 A and a lid side locking mechanism  374 B. The base side locking mechanism  374 A and the lid side locking mechanism  374 B are cooperatively positioned so that when the lid  354  is closed, the locking mechanisms  374  lockably engage with one another thus securing the lid  354  to the base  352 . The locking mechanism  374  also includes a knob, switch or button  376  for releasing the base side locking mechanism  374 A from the lid side locking mechanism  374 B so as to allow the lid  354  to be opened. In the illustrated embodiment, the indicator  368  is disposed in the button  376 . By way of example, the indicator  368  may be a sleep indicator that informs the user when the portable computer is in a sleep mode. An example of a locking mechanism that may be used can be found in U.S. patent application Ser. No. 09/755,622, titled, “LOCKING SYSTEM FOR A PORTABLE COMPUTER,” filed Jan. 5, 2001 and that has issued as U.S. Pat. No. 6,659,516, which is herein incorporated by reference. 
     In one embodiment, the notebook computer  350  includes a light adjustment circuit for adjusting the intensity of light outputted from the notebook computer  350 . By adjusting the light intensity, the power consumption of the notebook computer  350  can be reduced thereby increasing battery life. By way of example, the light adjustment circuit may correspond to the circuit described in  FIG. 2 . 
     The light adjustment circuit generally contains various light sources configured to emit light as well as one or more light sensors configured to measure the light level of the ambient light that surrounds the notebook computer  350  during use. The configuration of the light sources and sensors of the light adjustment circuit may be widely varied. For example, the light sources and light sensors may be positioned almost anywhere on the notebook computer  350  (e.g., base or lid). Furthermore, the light sources and light sensors may be located at peripheral locations around the notebook computer (e.g., exposed) or they may be located at internal locations within the notebook computer. In the later case, windows and light conduits may be used to transmit ambient light into the portable computer or output light out of the notebook computer. 
     In one implementation, the ambient light receiving means whether a light sensor, a window or a light conduit, is located on the mating surfaces of the base or lid. By mating surfaces, it is generally meant the surfaces that mate when the notebook computer  350  is closed, as for example, the surfaces that include the LCD  370  and keyboard  356 . When located on the mating surfaces, the portable computer  350  can sense when the lid  354  is closed (e.g., no ambient light) and thus when the notebook computer  350  is not in use. As a result, the notebook computer  350  can reduce the intensity of the light for each of the light sources thereby saving valuable battery life. 
     In the illustrated embodiment, the light adjustment circuit includes a first light source for lighting up the indicator  368  (e.g., LED), a second light source for lighting up the back lit keyboard  356  (e.g., LED) and a third light source for lighting up the LCD display  370  (e.g., light panel). In one particular embodiment, the backlit keyboard is configured to illuminate the legends disposed on the keyboard so that they glow when the light source is turned on. When turned off, the legends have a color that provides contrast with the rest of the key so that they are clearly visible when the light source is turned off (and the ambient light is high). In another embodiment, the backlit keyboard is configured to illuminate the area around the keys so as to define the edges of the keys. The light adjustment circuit also includes a pair of light sensors  380 , each of which is disposed within the base  352  of the notebook computer  350 , and more particularly behind a grill  382  of the speakers  362  disposed in the base  352 . As shown, the grill  382 , which includes a plurality of holes, is typically formed in the housing that forms the base  352 . The holes act as a window or light conduit for transmitting ambient light to the light sensors  380  disposed within the base  382 . As should be appreciated, the grill  382  is generally left exposed during use so as not to muffle the sound emanating therefrom and thus it is a good location for positioning the light sensors  380 , i.e., typically not covered. 
     In one particular embodiment, the keyboard light comes on in low ambient light, thereafter adjusts to the ambient light level and then automatically shuts off in brighter ambient light, i.e., the legend glows in dark conditions and reverts to its natural color in lighted conditions. 
       FIG. 8  is a side elevation view, in cross section, of a portable computer  400 , in accordance with one embodiment of the present invention. By way of example, the portable computer  400  may correspond to the notebook computer shown in  FIG. 7 . The portable computer  400  includes a housing  402  for enclosing a light sensor  404  that is attached to a printed circuit board  406 . The light sensor  404  may be attached to the printed circuit board  406  using any suitable and conventional means. By way of example, the printed circuit board  406  may correspond to the mother board of the portable computer  400 . As shown, the housing  402  includes a plurality of openings  408 . The openings  408  are preferable dimensioned to allow the passage of ambient light  410  so that the light sensor  404  can measure the intensity of the ambient light  410 . By way of example, the openings  408  may form the grill of a speaker. In one particular implementation, the openings  408  have a diameter of about 0.8 mm, and spacings therebetween of about 0.8 mm. Furthermore, the light sensor  404  generally represents a photodiode as for example, the photodiode BS520 manufactured by Sharp Microelectronics of America. 
       FIG. 9  is a side elevation view, in cross section, of a portable computer  420 , in accordance with an alternate embodiment of the present invention. The portable computer  420  is like the portable computer  400  shown in  FIG. 7 , however unlike the portable computer  400  shown in  FIG. 7 , the portable computer  420  includes a light guide  422  configured to focus the ambient light  410  onto the light sensor  404 . The light guide  422  is configured to receive the light  410  passing through the openings  408  and to direct the light  410  to the light sensor  404 . The light incident on the light sensor  404  is thus more intense than would otherwise be achievable without the light guide  422 . 
       FIG. 10  is a side elevation view, in cross section, of a portable computer  430 , in accordance with an alternate embodiment of the present invention. The portable computer  430  is like the portable computer  400  shown in  FIG. 7 , however unlike the portable computer  400  shown in  FIG. 7 , the portable computer  430  includes a lens  432  configured to focus the ambient light  410  onto the light sensor  404 . The lens  432  is configured to receive the ambient light  410  passing through the openings  408  and to direct it to the light sensor  404 . The light incident on the light sensor  404  is thus more intense than would otherwise be achievable without the lens  432 . 
       FIG. 11  is a side elevation view, in cross section, of a portable computer  440 , in accordance with an alternate embodiment of the present invention. By way of example, the portable computer  400  may correspond to the notebook computer shown in  FIG. 7 . In this particular embodiment, a light pipe  442  is configured to direct ambient light  410  from outside the housing  402  to inside the housing  402  towards the light sensor  404 . The light pipe  442  may be integrally formed with a window  444  located in a wall of the housing  402  or it may be a separate component. In the later case, the light pipe  442  may be configured to contact at least a portion of the window  444  or may include a gap therebetween. In a similar vein, the light pipe  442  may be configured to contact at least a portion of the light sensor  404  or may include a gap therebetween. Furthermore, the light pipe  442  may be structurally coupled to the housing  402  or it may be structurally coupled to the light sensor  404  or to the circuit board  406  to which the light sensor  404  is attached. As should be appreciated, the material that forms the light pipe  442  must be suitable to facilitate the transmission of light therethrough. In some implementations, the material corresponds certain types of plastics or other translucent materials. 
       FIG. 12  is a side elevation view, in cross section, of a portable computer  450 , in accordance with an alternate embodiment of the present invention. The portable computer  450  is like the portable computer  440  shown in  FIG. 11 , however unlike the portable computer  440  shown in  FIG. 10 , the portable computer  450  includes one or more flexible light pipes  452  configured to distribute light ambient light  410  to the light sensor  404 . Flexible light pipes typically allow a wider range of light sensor positions. For example, the light pipe  452  may be used to distribute the ambient light  410  to the light sensor  404  by bending around components disposed therebetween (e.g., walls, frames, I/O devices and the like). The light pipe  452  generally includes a transmissive portion at its interior and a reflective portion at its exterior. Because the exterior of the light pipe  452  is reflective (due to total internal reflection), the light  410  reflects off the sides of the pipe  452  as it travels through the interior of the light pipe  452 . Accordingly, when light  410  is made incident on an inner edge  458  of the light pipe  452  it is directed through the light pipe  452  via the transmissive and reflective portions to an outer edge  460  of the light pipe  452  where it emits the light  410  to another location positioned away from the location of the original ambient light  410 . 
       FIG. 13  is a side elevation view, in cross section, of a back lit keyboard  470 , in accordance with one embodiment of the present invention. By way of example, the back lit keyboard  470  may generally correspond to the back lit keyboard shown in  FIG. 7 . The keyboard  470  is configured to allow a user to input commands and other instructions to a portable computer  472 . For example, the keyboard  470  may allow a user of the portable computer  472  to enter alphanumeric data or to execute tasks such as GUI selections. As shown, the keyboard  470  includes a plurality of keys  474  that are attached to a base plate  476 . The keys  474  may be attached using any suitable arrangement. In the illustrated embodiment, the keys  474  are attached via a linkage  478  that allows the keys  474  to move up and down relative to the base plate  476 . By way of example, the linkage  478  may be a scissor mechanism. Although not shown, the base plate  476  generally includes a circuit layer that sends a signal to the portable computer  472  when a particular key  474  is pressed down. The base plate  476  may also include a spring element (not shown) for biasing the keys  474  in the up position. Furthermore, the keyboard  470  is positioned within an opening  477  of a base  478  of the portable computer  472 . The keyboard  470  may be held within the opening  477  using any suitable means (e.g., screws, bolts, etc.). In one embodiment, the keyboard  470  is removable so latches, hooks, snaps, magnets, and the like may be used to hold the keyboard  470  relative to the base  478 . 
     As shown, a light source  480  is disposed underneath the base plate  476 . The light source  480  is configured to provide light to the keyboard  470  so that the keyboard  470  can be illuminated. The illumination may be widely varied. The illumination may be provided in the space between the keys  474  so as to better define the edge of keys  474 . Alternatively or additionally, the illumination may be provided through the keys  474  so as to better define the keys  474 . In one embodiment, the legend  482  (e.g., letter or symbol) disposed on the keys  474  is illuminated rather than the entire key  474 . The base plate  476  is generally configured with one or more openings  484  so as to deliver the light from the light source  480  to the keys  474 . In essence, the openings  484  allow light emanating from the light source  480  to travel to and/or around the keys  474 , i.e., the light that passes through the opening  484  may be used to illuminate the space between the keys  474  and/or the keys  474  themselves. 
     Alternatively or additionally, the base plate or portions thereof may be formed from a translucent material thereby allowing the light to be transmitted therethrough. The light source may be widely varied. For example, the light source may be one or more light panels, a plurality of spaced apart light sources, and the like that directs light towards the backside of the base plate. In the illustrated embodiment, the light source  480  corresponds to a light panel that distributes light over an area. For example, it may be configured to distribute light towards the entire backside of the base plate  476  or it may distribute light to only a portion of the base plate  476 . Moreover, the light source  480  may be configured to contact at least a portion of the base plate  476  or it may include a gap therebetween (as shown). 
       FIG. 14  is an exploded perspective view of a back lit keyboard  500 , in accordance with one embodiment of the present invention. By way of example, the back lit keyboard  500  may generally correspond to the keyboard shown in  FIG. 13 . In this particular embodiment, the back lit keyboard  500  consists of a keyboard  502  and a light panel  504 . The keyboard  502  is configured to transmit light from the backside of the keyboard  502  where the light panel  504  is located to the opposite side where the keys  506  of the keyboard  502  are located. In one embodiment, the legends located on the keys  506  as well as the spaces located between the keys  506  are illuminated. As such, the keyboard  500  includes a path for distributing the light to the keys  506  as well as to the spaces  508  between the keys  506 . 
     As shown, the light panel  504  includes a plurality of optical fibers  510 . The optical fibers  510  are generally configured to allow light passing therethrough to escape through the outer surface of the optical fiber  510 . By way of example, the optical fibers may be scored at various locations along the length so that the light leaks out of the optical fiber. Furthermore, the optical fibers  510  are positioned adjacent one another in rows so as to form a sheet of optical fibers. The optical fibers  510  thus distribute light in a planar manner. In some cases, the optical fibers  510  are attached to a backing sheet  512  to help hold them together. The backing sheet  512  may also help direct the light in direction of the keyboard  502 , i.e., it may be a reflective surface that helps direct the light to one side of the light panel  504 . Furthermore, each of the optical fibers  510  are optically coupled to a light source  514 . For example, the ends of the optical fibers  510  may be positioned adjacent a light source  514  so that the light emanating from the light source  514  passes therethrough. By way of example, the light source may correspond to a light emitting diode (LED). In the illustrated embodiment, each of the optical fibers  510  extends into a light housing  516  that contains the light source  514 . The light housings  516  provide a means for connecting the ends of the optical fibers  510  proximate the light source  514  and they may help direct light from the light source  514  into the optical fibers  510 . In some cases, a cover  518  may be provided to protect the proximal portions of the optical fibers  510  as well as the light housing/light sources  514 / 516 . By way of example, the light panel described above may be manufactured by Poly-Optical of Irvine, Calif. 
     The configuration of the light panel  504  may be widely varied. In the illustrated embodiment, the light panel  504  is broken up into a plurality of strands  520 , each of which includes a plurality of optical fibers  510 . The optical fibers  510  from each strand may extend into a single light housing/light source  514 / 516  or they may extend into multiple light housing/light sources  514 / 516  (as shown). Each of the strands  520  is separated by a gap  522 . The gap  522  may allow space for fibers and other components that need to pass through the light panel  504 . The multiple edges of the strands  520  may also be used to help secure the light panel  504  to the back of the keyboard  502 . For example, the edges may be secured to the backside of the keyboard  502  with screws that trap the edge of the strands  520  between the screw and the backside of the keyboard  502 . The number of strands  520  may be widely varied. In one embodiment, the number of strands corresponds to the number of rows of keys on the keyboard  502 , i.e., for every row of keys there is a corresponding strand. This, however, is not a requirement as the number of strands may depend on other factors. 
     The light source  514  may be configured to distribute white or colored light. In some circumstances, the light source  514  itself is capable of producing different colors and in other cases different colored light sources  514  may be optically coupled to different optical fibers  510  from each strand  520  so that the color of light emanating from each strand  520  can be controlled. By way of example, the light panel  504  may be configured to change its color in a manner similar to that which is disclosed in U.S. patent application Ser. No. 10/075,964, titled, “ACTIVE ENCLOSURE FOR COMPUTING DEVICE,” filed Feb. 13, 2002 and published as Publication No. 2003/0002246, and U.S. patent application Ser. No. 10/075,520, titled, “COMPUTING DEVICE WITH DYNAMIC ORNAMENTAL APPEARANCE,” filed Feb. 13, 2002 and issued as U.S. Pat. No. 7,113,196, both of which are herein incorporated by reference. 
       FIG. 15  is a broken away side elevation view, in cross section, of a back lit keyboard  550 , in accordance with one embodiment of the present invention. By way of example, the back lit keyboard  550  may generally correspond to the back lit keyboard shown in  FIG. 13 . The back lit keyboard  550  generally includes a plurality of keys  552 , each of which is movably mounted to a base plate  554  via a scissor mechanism  556 . The scissor mechanism  556  provides stability to the keys  552  while allowing the keys  552  to move up and down. The keys  552  and the base plate  554  are both composed of various layers. The keys  552  include a translucent base layer  558  and an opaque mask layer  560 . The base layer  558  is configured to allow the passage of light therethrough. The mask layer  560 , on the other hand, is configured to cover the base layer  558  except at an opening  562 . Light is therefore allowed to pass through the base layer  558  and out the opening  562  in the mask layer  560 . The opening  562  generally defines a legend on the keys  552 . By way of example, the legend may correspond to letters, symbols and the like. The base layer  558  and the mask layer  560  may be widely varied. In one embodiment, the mask layer  560  is painted (e.g., primer and color coat) on the base layer  558 , which is formed from clear or translucent plastic, and then the mask layer  560  is laser etched to form the opening  562 . In some cases, the base layer  558  is also etched so as to produce a frosted surface. The frosted surface produces a uniform glow when the keys  552  are illuminated with light. 
     The base plate  554  includes a feature plate  568 , a switch membrane  570 , a rubber dome sheet  572  and a mask layer  574 . The feature plate  568  is configured to support the various layers of the keyboard  550  in their assembled position. The feature plate  568  includes an opening  576  underneath each of the keys  552 . The openings  576  provide an area where light may pass so as to illuminate the rest of the keyboard  500 . The base plate  554  may include a transparent disk  578  disposed in the opening  576  of the feature plate  568 . The transparent disk  578  is attached to the back of the switch membrane  570  and may be trapped between portions of the feature plate  568  and the switch membrane  570 . The transparent disk  578  is configured to provide rigidity at the opening  576  so as to prevent bowing in areas surrounding the opening  576  when the key  552  is pressed down while still allowing the passage of light. Although not shown in great detail, the scissor mechanism  556  is typically attached to the feature plate  568 . The feature plate may be formed from sheet metal such as stainless steel. 
     The switch membrane  570 , which is positioned over the feature plate  568 , carries the circuit switches used to drive the signals when the keys  552  are pressed down. The switch membrane  570  generally includes a flexible and translucent sheet with a circuit pattern formed thereon. The translucency of the sheet is configured to allow the passage of light therethrough. The switch membrane  570  typically includes a through hole  580  for the scissor mechanism  556 . In some cases, the switch membrane  570  may include a mask layer for preventing the passage of light therethrough although this is not a requirement. 
     The rubber dome sheet  572 , which is positioned over the switch membrane  570 , carries a plurality of rubber domes  582  that provide a biasing force to each of the keys  552 , i.e., they bias the keys upward. The user therefore must work against the biasing force (by pressing down on the key) in order to actuate the switch on the switch membrane  570 . The rubber dome sheet  572  is also formed from a translucent material so that light may pass therethrough. Like the switch membrane, the rubber dome  572  sheet also includes a through hole  584  for the scissor mechanism  556 . 
     The mask layer  574 , which is positioned over the rubber dome sheet  572 , covers the rubber dome sheet  572  except at an opening  586 . Light is therefore allowed to pass through the other layers and out the opening  586  in the mask layer  574 . In most cases, the mask layer  574  covers the areas of the base plate  554  between adjacent keys  552  thereby providing a uniform look between adjacent keys  552 . In the illustrated embodiment, the mask layer  574  starts at a point underneath the key  552 . The mask layer  574  may work with the mask layer of the switch membrane  570  to mask the desired portions of the base plate  554 . In most cases, the mask layer  574  is printed on the surface of the rubber dome sheet  572 . The mask layer  574  may be any color. In one particular implementation, the mask layer is gray. 
     The back lit keyboard  550  also includes a light panel  590 . The light panel  590  is disposed underneath the base plate  554  so as to illuminate the keyboard  550 . The light panel  590  may or may not be attached to the base plate  554 . In the illustrated embodiment, the light panel  590  is attached as for example using screws or bolts. As discussed previously, the light panel  590  generally includes a plurality of optical fibers  592  and a backing sheet  594 . The optical fibers  592  are typically formed from a clear material. In one implementation, one end of the optical fibers are connected to an LED and the opposite end is blocked. Moreover, the optical fibers are lined up in a sheet and scored (cut) so that light may leak therefrom, i.e., along the body of the fiber thread rather than only at its ends. By way of example, the optical fibers may have a diameter of about 0.1 inches. The optical fibers  592  are generally attached to the backing sheet  594  via an adhesive  596  such as glue. The backing sheet  594  helps to maintain the position of the optical fibers  592  and to direct the light emanating from the optical fibers  592  towards the back side of the base plate  554 . 
     As shown in  FIG. 15 , the light panel  590  transmits light towards the back side of the feature plate  568 . Light that intersects the feature plate  568  is blocked while light that intersects the opening  576  is allowed to continue on its path. The light traveling through the opening  576  in turn passes through the transparent disk  578 , the switch membrane  570  and the rubber dome sheet  572 . Thereafter, the light either intersects the mask layer  574  or the opening  586  in the mask layer  574 . Like the feature plate  568 , light that intersects the mask layer  574  is blocked while light that intersects the opening  586  is allowed to continue on its path. The light exiting the opening  586  in turn lights up the area between the keys  552  and the base plate  554 . Some of the light illuminates the keys  552  and some of the light illuminates the area between adjacent keys  552 . For example, some of the light passes through the base layer  558  of the key  552 . This light either intersects the mask layer  560  or the opening  562  in the mask layer  560 . The light that intersects the mask layer  560  is blocked while light that intersects the opening  562  is allowed to continue on its path. In most cases, the light exiting the opening  562  is diffused in some manner so as to produce a uniform glow at the top surface of the key  552 . Some of the light also passes through the gap formed between the key  552  and the base plate  554 . This light typically reflects off the top surface of the mask layer  574  thereby illuminating the area between adjacent keys  552 . 
       FIG. 16  is a top view, in cross section, of a portable computer  600 , in accordance with one embodiment of the present invention. By way of example, the portable computer  600  may correspond to the portable computer shown in  FIG. 7 . The portable computer  600  includes a housing  602  having a button  604  attached thereto. The button  604  is configured to move through a hole  606  in the housing  602  in order to actuate some feature of the portable computer  600 . For example, the button  604  may be used to release a locking mechanism that locks the lid to the base of the portable computer  600 . The housing  602  itself is configured to enclose internal components of the portable computer  600 . In the illustrated embodiment, the housing  602  encloses at least an indicator arrangement  608  for alerting the user when a computer event occurs. For example, the indicator arrangement  608  may be a used to indicate that the portable computer  600  is in a sleep mode. As shown, the indicator arrangement includes a light source  610 , a light pipe  612 , and a window  614 . The light source  610 , which is attached to a printed circuit board  616 , is configured to emit light inside the housing  602 . The light pipe  612 , which is also attached to the printed circuit board  616 , is configured to direct light from the light source  610  to the window  614 . The window  614 , which is incorporated within the button  604 , is configured to allow the passage of light therethrough so as to allow light emanating from the light source  610 , and more particularly light exiting the light pipe  612 , to travel outside the housing  602 , and more particularly the button  604 . In most cases, the light exiting the window  614  is diffused in some manner so as to produce a uniform glow at the surface of the window  614 . 
     As should be appreciated, the material that forms the light pipe  612  and window  614  must be suitable to facilitate the transmission of light therethrough. In some implementations, the material corresponds certain types of plastics or other translucent materials. In one particular implementation, the light pipe  612  includes a light receiving surface  620  and a light output surface  622 . The light receiving surface  620  is generally located proximate the light source  610  so as to collect light therefrom, and the light output surface  622  is generally directed towards and proximate to the window  614  so as to transmit light thereto. The other surfaces of the light pipe  612  are typically reflective due to total internal reflection and thus they tend to concentrate light through the light output surface  622 . Furthermore, the light source  610  may be selected from any suitable light emitting device. In the illustrated embodiment, the light source  610  corresponds to a side firing light emitting diode that directs light generally in one direction, as for example, the direction of the light receiving surface  620  of the light pipe  612 . 
     The light pipe  612  may be configured to contact at least a portion of the window  614  or may include a gap therebetween. The later is generally preferred so as not to obstruct the button  604  when it is moved inward. Alternatively, the light pipe  612  may be integrally formed with the window  614  thereby moving with the button  604 . In a similar vein, the light pipe  612  may be configured to contact at least a portion of the light source  610  or may include a gap therebetween. 
     It should be noted that the above configuration is not a limitation and that the indicator arrangement may vary according to the specific needs of each portable computer. For example, the window  614  may be located in a wall of the housing rather than the button. Furthermore, the light guide  612  may be attached to the housing  602  rather than to the circuit board  616 . 
     While this invention has been described in terms of several preferred embodiments, there are alterations, permutations, and equivalents, which fall within the scope of this invention. For example, although the invention was described primarily in terms of a notebook computer, it should be noted that this is not a limitation and that the invention can be implemented in other computing devices and more particularly other consumer electronic products. That is, it is contemplated that the present invention, whether completely or in part, may be adapted for any of a number of suitable and known computing devices or consumer electronic products that perform useful functions via electronic components (e.g., audio, video, computing, etc.). By way of example, the present invention may be incorporated into general purpose computers such as desktop computers that sit on desks, floors or other surfaces (both segmented and all-in-one machines), portable or handheld devices such as personal digital assistants (PDAs), mobile phones, media players (MP3 players), cameras (both video and photos) and the like. 
     It should also be noted that there are many alternative ways of implementing the methods and apparatuses of the present invention. For example, although the ambient light level range was given as 0 to 1000 lux, it should be noted that this is not a limitation and that it may extend above this range. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and equivalents as fall within the true spirit and scope of the present invention.

Metadata:
Filing Date: 20150302
Publication Date: 20171010
Grant Date: 20171010
Priority Date: 20021224
Inventors: KERR DUNCAN
ORDING BAS
CHRISTIE GREG
CHAUDHRI IMRAN
VAN OS MARCEL
KING NICK
Assignee: APPLE INC
CPC Classifications: [{"code": "G09G2330/021", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3406", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/0633", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G5/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2360/144", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3406", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/0633", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2360/144", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2330/021", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05B45/22", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3406", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2330/021", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2320/0633", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05B33/0869", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G5/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02B20/46", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05B37/0218", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1616", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2360/144", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05B33/0854", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05B45/12", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05B47/11", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1616", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05B45/12", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1616", "inventive": true, "first": true, "tree": "[]"}, {"code": "Y02B20/40", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y02B20/40", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 38178791