PATENT DOCUMENT

Publication Number: US-10614775-B2
Application Number: US-201815979315-A
Country: US
Kind Code: B2

Title: Electronic devices having backlit keyboards displays with adjustable white points

Abstract:
An electronic device may have a main display and an ancillary display that forms a dynamic function row. The device may also have a backlit keyboard with glyphs. The keyboard may have light-emitting diodes that emit backlight illumination. The backlight illumination has a backlight illumination color and intensity. A color ambient light sensor may measure ambient light color and intensity. Control circuitry in the laptop computer may make white point adjustments to the main and ancillary displays. White point adjustments may be made based on factors such as the backlight illumination intensity, information on the nominal white point of a display (which may be comparable to the color of the backlight illumination), information on the ambient light color and intensity, and a white point adaptation scaling factor.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 a first display with a first white point; 
 a second display with a second white point; 
 a keyboard having a light source configured to emit backlight illumination and keyboard keys that are illuminated by the backlight illumination, wherein the backlight illumination has a backlight illumination intensity: 
 a color ambient light sensor; and 
 control circuitry configured to adjust the second white point at least partly in response to information from the color ambient light sensor and at least partly based on the backlight illumination intensity. 
 
     
     
       2. The electronic device defined in  claim 1  wherein the electronic device comprises a base housing and a display housing that are coupled by a hinge and wherein the first display is mounted in the display housing. 
     
     
       3. The electronic device defined in  claim 2  wherein the keyboard is in the base housing and the second display is in the base housing. 
     
     
       4. The electronic device defined in  claim 3  wherein the second display is adjacent to the keyboard and the first display and wherein the second display includes a touch sensor. 
     
     
       5. The electronic device defined in  claim 4  wherein keyboard keys each have a glyph through which the backlight illumination passes. 
     
     
       6. The electronic device defined in  claim 5  wherein the control circuitry is configured to adjust the first white point based at least partly on the information from the color ambient light sensor. 
     
     
       7. The electronic device defined in  claim 5  wherein the information from the color ambient light sensor comprises ambient light color and ambient light intensity and wherein the control circuitry is configured to adjust the second white point based at least partly on the ambient light color and the ambient light intensity. 
     
     
       8. The electronic device defined in  claim 7  wherein the backlight illumination has a backlight illumination color and wherein the control circuitry is configured to adjust the second white point based at least partly on the ambient light color, the ambient light intensity, and the backlight illumination intensity. 
     
     
       9. A laptop computer, comprising:
 a display housing; 
 a first display mounted in the display housing; 
 a base housing that is rotatably coupled to the display housing; 
 a keyboard in the base housing having a plurality of keyboard keys; 
 a second display adjacent to the keyboard; 
 a color ambient light sensor configured to measure ambient light color and ambient light intensity; and 
 control circuitry configured to display content on the second display with a white point that is selected based on the ambient light color, the ambient light intensity, and a white point adaptation scaling factor. 
 
     
     
       10. The laptop computer defined in  claim 9  wherein the white point adaption scaling factor has a value of 0.1 to 0.6, wherein the second display is characterized by a D65 white point, and wherein the selected white point has a color that is between the D65 white point and the ambient light color. 
     
     
       11. The laptop computer defined in  claim 9  further comprising light-emitting diodes that supply backlight illumination for the keyboard keys, wherein the backlight illumination has a backlight illumination color and a backlight illumination intensity and wherein the control circuitry is configured to select the white point for the second display based at least partly on the backlight illumination intensity. 
     
     
       12. The laptop computer defined in  claim 11  wherein the keyboard keys are illuminated with backlight illumination having a backlight illumination intensity and wherein the control circuitry is configured to select the white point for the second display based at least partly on the backlight illumination intensity. 
     
     
       13. The laptop computer defined in  claim 9  wherein the control circuitry is configured to adjust a color cast associated with displaying content on the first display based on the ambient light color. 
     
     
       14. An electronic device, comprising:
 a main display on which first content is displayed with a first white point; 
 a keyboard having keys with glyphs that are illuminated using backlight illumination from light-emitting diodes, wherein the backlight illumination has a backlight illumination intensity; 
 a dynamic function row display on which second content is displayed with a second white point; 
 a color ambient light sensor that measures ambient light color and ambient light intensity; and 
 control circuitry configured to:
 adjust the first white point based on the ambient light color; and 
 adjust the second white point based on the ambient light intensity and the backlight illumination intensity. 
 
 
     
     
       15. The electronic device defined in  claim 14  wherein the control circuitry is further configured to adjust the second white point based on the ambient light color. 
     
     
       16. The electronic device defined in  claim 15  wherein the control circuitry is configured to adjust the second white point based on a white point adaptation scaling factor. 
     
     
       17. The electronic device defined in  claim 14  wherein the electronic device comprises a base housing and a display housing that are coupled by a hinge and wherein the main display is mounted in the display housing. 
     
     
       18. The electronic device defined in  claim 17  wherein the control circuitry is further configured to adjust the first white point based on the ambient light color.

Description:
This application claims the benefit of provisional patent application No. 62/542,727, filed Aug. 8, 2017, which is hereby incorporated by reference herein in its entirety. 
    
    
     FIELD 
     This relates generally to electronic devices and, more particularly, to electronic devices with displays. 
     BACKGROUND 
     Electronic devices often include displays. For example, a laptop computer may have a color display for displaying images for a user. Laptop computers may also have keyboard keys and other input-output devices. 
     During operation, the intensity and color of ambient lighting may change. If care is not taken, ambient light changes and changes in the operating settings of components in the laptop computer may cause the appearance of keyboard keys, displays, and other input-output devices to vary in ways that are not visually appealing. 
     SUMMARY 
     An electronic device may have a main display and an ancillary display that forms a dynamic function row. The device may also have a backlit keyboard with glyphs adjacent to the ancillary display. The keyboard may have light-emitting diodes that emit backlight illumination for the glyphs. 
     The backlight illumination of the keyboard has a backlight illumination color and intensity. A color ambient light sensor may measure ambient light color and intensity. 
     White point adjustments may be made based on factors such as the backlight illumination intensity, information on the nominal white point of a display (which may be comparable to the color of the backlight illumination), information on the ambient light color and intensity, and a white point adaptation scaling factor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an illustrative electronic device such as a laptop computer in accordance with an embodiment. 
         FIG. 2  is a schematic diagram of an illustrative electronic device in accordance with an embodiment. 
         FIG. 3  is a perspective view of an illustrative keyboard key with a glyph in accordance with an embodiment. 
         FIG. 4  is a color space diagram showing how the apparent color of keyboard key glyphs can change as a function of ambient lighting and keyboard backlighting conditions and showing how display color adjustments may be made in accordance with an embodiment. 
         FIG. 5  is a flow chart of illustrative operations involved in using an electronic device such as the device of  FIG. 1  in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices such as cellular telephones, laptop computers, tablet computers, electronic devices in embedded systems such as systems in homes and vehicles or other embedded system equipment, and other devices may have input-output devices for gathering input and providing a user with output. The input-output devices may include displays, touch screen displays, keyboards, and other input-output components. 
     Aspects of the appearance of input-output components such as these may be adjusted during device operation to ensure that an electronic device is visually appealing to a user. For example, the white point of one or more displays may be adjusted depending on changes in ambient lighting conditions and other variables. 
     An illustrative electronic device in which the white point of displayed content can be adjusted is shown in  FIG. 1 . Device  10  of  FIG. 1  is a laptop computer. If desired, device  10  may be a computer monitor containing an embedded computer, a tablet computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wrist-watch device, a pendant device, a headphone or earpiece device, a device embedded in eyeglasses or other equipment worn on a user&#39;s head, or other wearable or miniature device, a display, a computer display that contains an embedded computer, a computer display that does not contain an embedded computer, a gaming device, a navigation device, an embedded system such as a system in which electronic equipment with a display is mounted in a kiosk or automobile, or other electronic equipment. The laptop computer of  FIG. 1  is merely illustrative. 
     As shown in the example of  FIG. 1 , device  10  may have a housing such as housing  12 . Housing  12  may be formed from plastic, metal (e.g., aluminum), fiber composites such as carbon fiber, glass, ceramic, other materials, and combinations of these materials. Housing  12  or parts of housing  12  may be formed using a unibody construction in which housing structures are formed from an integrated piece of material. Multipart housing constructions may also be used in which housing  12  or parts of housing  12  are formed from frame structures, housing walls, and other components that are attached to each other using fasteners, adhesive, and other attachment mechanisms. 
     Device  10  may have a one-piece housing or a multi-piece housing. As shown in  FIG. 1 , for example, electronic device  10  may be a device such as a portable computer or other device that has a two-part housing formed from an upper housing portion such as upper housing  12 A and lower housing portion such as lower housing  12 B. Upper housing  12 A may include a display such as display  14  and may sometimes be referred to as a display housing or lid. Lower housing  12 B may sometimes be referred to as a base housing or main housing. 
     Housings  12 A and  12 B may be rotatably coupled to each other using hinges  26  along the upper edge of lower housing  12 B and the lower edge of upper housing  12 A. Hinges  26  may be located at opposing left and right sides of housing  12  along hinge axis  22 . Hinges  26  may allow upper housing  12 A to rotate about axis  22  in directions  24  relative to lower housing  12 B. The plane of lid (upper housing)  12 A and the plane of lower housing  12 B may be separated by an angle that varies between 0° when the lid is closed to 90°-140°, or more when the lid is fully opened. 
     As shown in  FIG. 1 , device  10  may have input-output devices such as track pad  18  and keyboard  16 . Track pad  18  may be formed from a touch sensor that gathers touch input from a user&#39;s fingers. Keyboard  16  may have an array of keys  16 K that protrude through openings in the upper wall of housing  12 B. 
     Display  14  may serve as a primary display for device  10  and may sometimes be referred to as a main display. Device  10  may also have one or more additional displays such as ancillary display  20 . Ancillary display  20  may be touch sensitive and may serve to display interactive reconfigurable visual elements (icons such as function-key buttons, image thumbnails, etc.). Because ancillary display  20  can be used to display content such as dynamically adjustable function keys, ancillary display  20  may sometimes be referred to as a dynamic function row or dynamic function row display. In general, any suitable content may be displayed on display  20 . 
     In the example of  FIG. 1 , ancillary display  20  has an elongated shape (e.g., a long thin rectangular shape) that allows ancillary display  20  to be mounted to base housing  12 B adjacent to the uppermost row of keyboard keys  16 K in keyboard  16 . In this location, ancillary display  20  lies between the upper edge of keyboard  16  and the lower edge of main display  14  and is therefore adjacent to both keyboard  16  and main display  14 . There is a single ancillary display  20  in the illustrative configuration for device  10  that is shown in  FIG. 1 . Additional ancillary displays may be included in device  10 , if desired. 
     Display  14  and/or display  20  may be a liquid crystal display (LCD), a plasma display, an organic light-emitting diode (OLED) display, an electrophoretic display, or a display implemented using other display technologies. A touch sensor may be incorporated into displays  14  and/or  20  (i.e., display  14  may be a touch screen display and/or display  20  may be a touch screen display). With one illustrative configuration, which may sometimes be described herein as an example, main display  14  may be liquid crystal display or organic light-emitting diode display that is insensitive to touch and ancillary display  20  may be an elongated touch sensitive display such as a touch sensitive organic light-emitting diode display (e.g., a dynamic function row display that includes a two dimensional touch sensor that overlaps an array of pixels in display  20 ). Other configurations may be used, if desired. 
     Touch sensors for a touch sensitive display such as ancillary display  20  may be resistive touch sensors, capacitive touch sensors, acoustic touch sensors, light-based touch sensors, force sensors, or touch sensors implemented using other touch technologies. With one illustrative configuration, ancillary display  20  may include an array of capacitive touch sensor electrodes that form a capacitive touch sensor for display  20 . 
     If desired, device  10  may also have components such as a camera, microphones, speakers, buttons, status indicator lights, sensors, and other input-output devices. These devices may be used to gather input for device  10  and may be used to supply a user of device  10  with output. Ports in device  10  may receive mating connectors (e.g., an audio plug, a connector associated with a data cable such as a Universal Serial Bus cable, a data cable that handles video and audio data such as a cable that connects device  10  to a computer display, television, or other monitor, etc.). 
     As shown in  FIG. 1 , device  10  may include light sensing components such as one or more ambient light sensors  30 . An ambient light sensor  30  may, for example, be mounted behind a portion of display  14  or may be mounted in base housing  12 B or other parts of device  10 . Ambient light sensor(s)  30  may be used in gathering information on ambient lighting conditions. For example, a monochrome ambient light sensor (or sensors) may be used in gathering ambient light intensity information. If desired, device  10  may have color ambient light sensors (e.g., light sensors that measure ambient light color and ambient light intensity). Color measurements may produce color data such as color coordinates (e.g., CIE x and y) and color temperature information (e.g., correlated color temperatures). During operation, device  10  can make adjustments to the color of content on display  14  and/or display  20  and may make adjustments to keyboard backlighting for keys  16 K based on light intensity and/or color information from sensors  30 . Color adjustments may also be made based information such as the brightness settings for keyboard keys  16 K. In some configurations, display adjustments can be made based on user input (e.g., keypress input, user input to a selectable icon on display  20 , user selection of menu options presented on display  14 , or other user input). User input may, as an example, be used to raise or lower screen brightness, to adjust automatic keyboard backlight brightness adjustment functions, to manually sets a keycard brightness level, etc.). 
     The color of keys  16 K is affected by the color of backlight illumination passing through keys  16 K and the color of ambient light reflecting off of keys  16 K. Keys  16 K may have symbols such as white alphanumeric characters and other symbols—sometimes referred to as glyphs. The color of backlight illumination passing through these symbols and the color of the ambient light reflecting off of the front of these symbols gives keys  16 K (e.g., the white portion of keys  16 K) an apparent color when viewed by a user of device  10 . In some scenarios, there is a potential for mismatch between the apparent color of keys  16 K and the color of images on displays such as display  20  and/or  14 . Display content can be characterized by a white point (color cast). When the white point of a display is set to a fixed value (e.g., the CIE Standard Illuminant D65), there is a potential for mismatch between the white point of the display and the apparent color of keys  16 K. For example, in bright cold lighting, keys  16 K may have a much colder color than content on the display. Particularly when displaying content on ancillary display  20 , which is adjacent to keys  16 K, it may be desirable to minimize the difference between the white point of display  20  and the apparent color of keys  16 K to avoid an undesirable visual conflict between these two light sources. 
     To avoid this potential conflict, device  10  may adjust the white point of display  20  and/or display  14  to help reduce significant differences between the color cast of displayed images and the apparent color of keys  16 K. 
     A schematic diagram showing illustrative components that may be used in device  10  is shown in  FIG. 2 . As shown in  FIG. 2 , device  10  may include control circuitry  40 . Control circuitry  40  may include storage such as hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in circuitry  40  may be used to control the operation of device  10 . This processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, application specific integrated circuits, etc. 
     Circuitry  40  may be used to run software on device  10 , such as internet browsing applications, voice-over-internet-protocol (VOIP) telephone call applications, email applications, media playback applications, an operating system or other software that controls display operations associated with adjusting the color cast (white point) for displayed content, software associated with adjusting display brightness, software for controlling adjustments to keyboard backlighting brightness, etc. To support interactions with external equipment, circuitry  40  may be used in implementing communications protocols. The software (code) for implementing these functions may be stored in a non-transistory storage medium (e.g., non-volatile memory, etc.). When configured appropriately by software code, circuitry  40  can ensure that displayed content such as content displayed on ancillary display  20  will have a color cast that is aesthetically appealing (e.g., a color cast that is matched to or that is at least adjusted towards the color of glyphs on keyboard keys  16 K, etc.). 
     Electronic device  10  may include input-output devices  42 . Input-output devices  42  may be used by a user to supply data to device  10  and/or may be used to gather data from the environment surrounding device  10 . Input-output devices  42  may also be used to provide data from device  10  to external devices and/or to supply output to a user. Input-output devices  42  may include ambient light sensor(s)  30 , keyboard keys  18 K, displays such as main display  14  and ancillary touch screen display  20 , and may include other components  44 . Components  44  may include user interface devices, data port devices, and other input-output components. For example, components  44  may include touch screens, displays without touch sensor capabilities, buttons, scrolling wheels, touch pads, key pads, keyboards, microphones, cameras, buttons, speakers, status indicators, light sources, audio jacks and other audio port components, digital data port devices, light sensors, light-emitting diodes, motion sensors (accelerometers), capacitance sensors, proximity sensors, magnetic sensors, force sensors (e.g., force sensors coupled to a display to detect pressure applied to the display), wireless circuitry, etc. 
     A perspective view of an illustrative keyboard key in keyboard  16  is shown in  FIG. 3 . As shown in  FIG. 3 , keyboard key  16 K may have a key member (sometimes referred to as a key cap) such as key member  52 . Surface  52 B of key member  52  may have a dark color (e.g., black) or other suitable color. A glyph such as glyph  52 G may be present on the face of key member  52 . Glyph  52 G (e.g., an alphanumeric character or other keyboard key symbol) may serve as a label for key  16 K and may be formed from white ink or other material that is visible against the background presented by the dark color on surface  52 . If desired, keyboard keys such as key  16 K may have other configurations (e.g., configurations in which glyphs are formed by printing black labels surrounded by white backgrounds). The configuration of  FIG. 3  in which surface  52 B is dark (e.g., black) and in which glyph  52 G has a lighter color such as white may sometimes be described herein as an example. 
     Keyboard key  16 K may be backlit. For example, a light source such as light-emitting diode  58  (e.g., a white light-emitting diode or other backlight illumination source) may emit light  60  that is blocked by surface  52 B and allowed to pass through glyph  52 G, which is translucent. Light transmitted through glyph  52 G (e.g., transmitted light  62 ) may be viewed by a user such as user  54  who is viewing keyboard key  16 K in direction  56 . At the same time, ambient light may reflect off of key  16 K. As a result, viewer  54  will generally observe a mixture of keyboard backlight illumination and reflected ambient light when viewing key  16 K. 
     The apparent color of key  16 K (glyph  52 G) to viewer  54  is therefore influenced by the color of transmitted light  62  and reflected ambient light (e.g., ambient light  66  from ambient light source  64  that has reflected off of glyph  52 G as reflected ambient light  68 ). In scenarios in which glyphs  52 G are formed from white ink, relatively small color changes are imparted to transmitted light  62  and reflected light  68  by the ink making up glyphs  52 G. Accordingly, the impact of the color of the ink in glyphs  52 G can be neglected. 
     The color of transmitted light  62  (sometimes referred to as keyboard light, keyboard key light, keyboard backlight illumination, keyboard key illumination, etc.) is determined by the color of diode  58 . With one illustrative arrangement, diode  58  may produce white light with a correlated color temperature (CCT) of 6000K (or 6500K, etc.). This color closely matches the white point used for displays  20  and  14  (e.g., when displays  20  and  14  have D65 white points). The color of reflected ambient light  68  depends on the operating environment of device  10  (e.g., outdoors in cold light, indoors in warm light, etc.). 
     The apparent color of key  16 K depends on the color of light  62  and the color of light  68  and relative intensities of these two types of light. In very bright ambient lighting conditions, light  62  is overwhelmed by reflected light  68 , so the apparent color of key  16 K will match the color of light  68 . In dim ambient lighting conditions, where the intensity of backlight  62  is much greater than that of ambient light  68 , the color of light  62  will dominate. 
     During operation, device  10  (e.g., control circuitry  40 ) may adjust the magnitude of the backlight illumination  60  produced by light-emitting diode  58 . For example, automatic adjustments to light-emitting diode  58  may be made in response to ambient light sensor measurements of ambient light intensity levels (e.g., if a user has previously directed device  10  to automatically illuminate keyboard  16  in low light). Control circuitry  40  may also set the backlight intensity for keyboard  16  based on a user selected brightness level. As a user uses device  10 , the user may place device  10  in a dim or brightly lit environment. To determine the color of keys  16 K, device  10  can make ambient light measurements with ambient light sensor  30  (e.g., measurements of ambient light color and ambient light intensity). Device  10  can also use control circuitry  40  to determine the current operating setting for diode  58  and can therefore determine the current state of the keyboard backlight illumination. The current brightness setting for diode  58  can be used in determining the intensity of light  62  and the known color temperature of diode  58  can be used in determining the color of light  62 . With this information, control circuitry  40  can determine the color of each keyboard key  16 K and can take appropriate action. For example, control circuitry  40  can adjust the white point of display  20  to reduce mismatch between the white point of display  20  and the apparent color of keys  16 K. 
       FIG. 4  is a color space diagram (e.g., a portion of the CIE 1931 color space in which color is represented in terms of color coordinates x and y) illustrating how device  10  can make color adjustments to display  20  in different operating scenarios. In the example of  FIG. 4 , keyboard backlight illumination  62  (diode  58 ) has a color represented by point P 1  (e.g., a 6000K correlated color temperature) and display  20  has a white point represented by point P 1 ′ (e.g., D65). These colors are close to each other, so in low ambient lighting conditions when display  20  has a D65 white point and keys  16 K have a 6000K color temperature, there will not be an excessive mismatch in the colors of display  20  and keys  16 K. 
     At larger ambient light levels, the appearance of keys  16 K can change significantly. In the example of  FIG. 4 , three different ambient lighting scenarios are present. In the first scenario, ambient light has a color represented by point P 2 . In the second and third scenarios, ambient light has colors represented by points P 3  and P 4 , respectively. Point P 2  represents warm ambient light. Point P 4  represents cold ambient light. Point P 3  (in this example) represents light with a greenish color. 
     The apparent color of key  16 K depends on the relative intensity of ambient light  68  to key backlight  62  and lies along curves such as curves  70 ,  72 , and  74 , depending on whether the ambient light color is represented by point P 2 , point P 3 , or point P 4 , respectively. The relative intensity of ambient light  68  to backlight  62  can be represented by a ratio R, where R is equal to ambient light intensity divided by backlight intensity. The value of R determines the location on each curve (curve  70 ,  72 , or  74  in this example) where the color of key  16 K lies. 
     Consider, as an example, the situation in which ambient light  68  has the warmish color represented by point P 2 . In this situation, the apparent color of key  16 K will be represented by a point that lies somewhere along curve  70 . When ambient light is not present (R=0), the color of key  16 K will be determined by the color of backlight  62 . As a result, the color of key  16 K will be represented by point P 1  when R is 0. When ambient light  68  is very strong and/or diode  58  is off (R is infinite), the apparent color of key  16 K will be represented by point P 2 . At intermediate values of R, the apparent color of key  16 K will lie midway between point P 1  and P 2  on curve  70 . For example, in a typical office lighting environment, where the value of R is 3 (as an example), the apparent color of key  16 K may be represented by point P 5  on curve  70 . 
     To ensure that display  20  has a color that does not vary too much from that of keys  16 K, control circuitry  40  may adjust the white point of display  20  along a curve such as display color adjustment curve  70 ′ in accordance with the measured value of R. Curve  70 ′ is similar to curve  70 , but uses the default white point of display  14  and/or  20  (e.g., D65 in the example of  FIG. 4 ) as its origin P 1 ′. The color of point P 1 ′ (the display white point prior to adjustment) is sufficiently close to that of point P 1  (the color of the backlight illumination for keys  16 K) that these points can be taken to be equivalent (e.g., P 1 ′ can be taken to be the origin of color adjustment curve  70 ′ and any differences between the colors at points P 1 ′ and P 1  can be neglected). The length of curve  70 ′ (e.g., the distance between point P 1 ′ and point P 2 ′) differs from the length of curve  70 , because curve  70 ′ has been scaled using a scaling factor SF (sometimes referred to as a white point adaption scaling factor, etc.). The use of scaling factor SF helps avoid over-adjustment of the white point (which a user of device  10  might find to be visually unappealing). When scaling factor SF is used, the length of the color adjustment curve will be reduced (e.g., curve  70 ′ will be shorter than curve  70 ) so that color adjustments will be more modest than if the white point of display  20  were exactly matched to apparent color of keys  16 K. The amount by which the white point of the display is adjusted with curve  70 ′ is therefore reduced in magnitude (in accordance with the scaling factor) relative to the amount by which the color of keys  16 K varies over curve  70 . 
     Scaling factor SF may have a value between 0 and 1. When the scaling factor is 0, no color adjustments to display  20  take place. When the scaling factor is 1, the white point of display  20  is adjusted between P 1 ′ when R is 0 and P 2  when R is infinite. When the scaling factor has an intermediate value (e.g., a value of 0.2-0.5, 0.1-0.6, at least 0.15, less than 0.5, less than 0.4, less than 0.3, or other suitable value between 0 and 1), the amount of color adjustment that is made to the color of display  20  will follow modified (scaled) color adjustment curve  70 ′ of  FIG. 4 . 
     When a scaled color adjustment curve such as curve  70 ′ is used, the white point of display  20  will be set to P 1 ′ when R is zero and will be set to P 2 ′ when R is infinite. At intermediate values of R, control circuitry  40  will adjust display  20  to have a white point that lies in a corresponding intermediate location along scaled color adjustment curve  70 ′ such as point P 5 ′. Color P 2 ′ is a color that is intermediate between P 1 ′ and P 2 , but that does not equal P 2  because of the user of a scaling factor SF that is less than 1 (e.g., 0.2-0.5, etc.). The white point adjustments that are made to display  20  with this approach (curve  70 ′) are less severe than non-scaled white point adjustments (curve  70 ) and may therefore be more visual pleasing to the user. 
     A flow chart of illustrative operations involved in using device  10  to make color adjustments to harmonize the appearance of keyboard keys  16 K and display  20  is shown in  FIG. 5 . 
     During the operations of block  80 , control circuitry  40  may use color ambient light sensor  30  to gather information on the color and intensity of ambient light in the vicinity of device  10  (e.g., ambient light  66  and  68  of  FIG. 3 ). 
     During the operations of block  82 , control circuitry  40  may determine the color and intensity of the backlight illumination for keys  16 K (e.g., backlight  60  and  62  of  FIG. 3 ). The color of the backlight illumination for keys  16 K is known from the known color of diode  58 , which may be retained in storage in control circuitry  40 . Diode  58  may, as an example, have a coordinated color temperature of 6000K, may be a D65 diode, or may be a diode that emits other light (e.g., other white light). The intensity of backlight illumination from diode  58  as a function of keyboard brightness setting can be measured (e.g., calibrated) during manufacturing and this information stored in storage in control circuitry  40  for use during the operations of block  82 . 
     During the operation of block  84 , control circuitry  40  may determine the relative contributions of ambient light and keyboard backlight to the appearance of glyphs  52 G. With one illustrative arrangement, control circuitry  40  may generate a white point adjustment curve such as curve  72 ′ based on the white point of display  20  (point P 1 ′ of  FIG. 4 ) and the ambient light color (point P 2 ) and based on the scaling factor SF (e.g., a value of 0.2-0.5 or other suitable scaling factor that adjusts the length of curve  70 ′). The location of the adjusted white point of display  20  is located at a point along white point adjustment curve  70 ′ that is determined by the relative contributions of ambient light and key backlight. The adjusted white point value may be identified by computing the ratio R by dividing ambient light intensity by keyboard backlight intensity and using this value of R to determine the location of the adjusted white point on curve  70 ′ or by otherwise taking into consideration the relative contributions of the ambient light and keyboard backlight to determine the apparent color of keys  16 K. After determining an appropriate adjusted white point to use for display  20 , display  20  can be adjusted to exhibit the new white point (e.g., content may be displayed on display  20  in accordance with the selected white point). If desired, display  14  may be adjusted to exhibit the same white point (or a white point adjustment may be made for display  14  using a larger or smaller scaling factor or using other adjustment techniques). In some configurations, the white point for display  20  may be adjusted without adjusting the white point of display  14  or the white point for display  14  may be adjusted without adjusting the white point of display  20 . 
     The foregoing is merely illustrative and various modifications can be made to the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20180514
Publication Date: 20200407
Grant Date: 20200407
Priority Date: 20170808
Inventors: JOHNSON, PAUL V.
ZHANG, LU
WU, JIAYING
Assignee: APPLE INC
CPC Classifications: [{"code": "G09G2320/062", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0202", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G5/02", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1662", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1681", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1662", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2360/144", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1692", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2360/144", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G5/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/0666", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1616", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/0666", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/1423", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/165", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1692", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/0666", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/1423", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/062", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1616", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2360/144", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1662", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1681", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0202", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G3/34", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G5/02", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09G5/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/165", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1616", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/1423", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/062", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/34", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G5/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1692", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 65274218