Display control for the always-on display mode of a computing device

Abstract

Systems and methods are provided herein for refreshing pixels of a display operating in an always-on mode. The method includes identifying a plurality of pixels of the display that are activated while the display is operating in the always-on mode, and dividing the plurality of pixels into at least a first pixel subset and a second pixel subset, the first pixel subset and the second pixel subset being mutually exclusive. The method may also include alternately activating and deactivating the first pixel subset and the second pixel subset.

Description

Technical Field

[0001] The present disclosure relates to controlling the display of a computing device. Specifically, the present disclosure generally relates to controlling the display screen of a computing device, particularly a wearable computing device such as a smartwatch or other smart wearable device. Specifically, aspects of the disclosed invention utilize a high-resolution organic light-emitting diode ( "OLED") display to periodically turn off different pixel sets on the display, providing a full image for display such that a user can seemingly continuously view the display screen at a glance, while also helping to prevent visual artifacts from occurring on the display.

Background Art

[0002] In mobile computing devices, particularly smart wearable devices, it is desirable to present content for display in a quickly accessible and visible manner. The goal is to enable the user to access information by viewing the content and / or to execute actions such as button presses quickly without explicitly invoking the main system display. A common way to achieve this is to put the mobile computing device into an "always-on display" ( "AOD") mode. In AOD mode, content is displayed on the screen even when the user is not explicitly interacting with the device.

[0003] Mobile computing devices spend most of their time in an idle state. This is particularly true for wearable computing devices, as user interactions with wearable computing devices are short and often omitted. Thus, wearable computing devices spend most of their time in AOD mode, displaying the same content for long periods of time.

[0004] When an OLED display displays still image content for a long time, it is prone to image persistence, which appears as a visual artifact of the still image "beneath" the newly displayed content shown when the screen is refreshed. These visual artifacts appear as "ghosts" or duplicates of previously displayed images. The presence of these visual artifacts can be essentially temporary, but may indicate a problem or defect in the quality of the display. In some cases, the visual artifacts are permanent and "burn in", making the visual artifacts permanently visible.

[0005] Existing solutions for reducing visual artifacts include the use of more expensive and high-performance OLED panels, or user interface solutions that shift the content across the screen to minimize the proportion of time that a still image is displayed. SUMMARY OF THE INVENTION

[0006] Aspects and advantages of embodiments of the present disclosure are shown in part in the following description, or can be learned from the description, or can be learned through the practice of the embodiments.

[0007] In one embodiment, a method for refreshing pixels of a display operating in an always-on mode can be provided. The method includes identifying a plurality of pixels of the display that are activated while the display is operating in the always-on mode, and dividing the plurality of pixels into at least a first pixel subset and a second pixel subset, wherein the first pixel subset and the second pixel subset are mutually exclusive. The method may also include alternately activating and deactivating the first pixel subset and the second pixel subset.

[0008] These and other features, aspects, and advantages of the various embodiments of the present disclosure will become better understood with reference to the following description and the appended claims. The accompanying drawings, which are incorporated herein and constitute a part of this specification, illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the relevant principles.

[0009] A detailed description of embodiments directed to those skilled in the art is set forth herein, which reference the accompanying drawings.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0011] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the present disclosure and is not a limitation of the present disclosure. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the present disclosure. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still another embodiment. Accordingly, the present invention is intended to embrace such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0012] The present disclosure generally relates to controlling a display screen of a computing device, and more particularly, a wearable computing device such as a smartwatch or other smart wearable device. Specifically, aspects of the disclosed invention utilize an OLED display to periodically turn off different pixel sets on the display to provide a full image for a display such that a user can seemingly continuously view the display screen while also helping to prevent visual artifacts from occurring on the display.

[0013] The proposed invention utilizes the use of a high-resolution OLED display to address the deficiencies of prior systems by periodically turning off different pixel sets while the content is being displayed in AOD mode. This enables the "relaxation" of the pixel level of the afterimage elements while continuously displaying an image with static elements in AOD mode. The pixels displaying the content can be subdivided into pixel groups. Each pixel group can represent the displayed content with complete representation, except that the overall resolution is lower (e.g., 160 ppi instead of 320 ppi) than if each pixel remained permanently on to display the content. Next, each pixel group can be turned off while other pixel groups remain on or are turned back on, thereby sequentially relaxing the pixels of each group. When the circulation of each pixel set is completed, the entire screen area of the display is "refreshed", and if it can be continuously circulated in this way, local pixel-level relaxation is possible while the computing device continuously displays the desired image content for a long time during AOD mode.

[0014] This method of controlling pixel relaxation in a pixel group is advantageous because it can be implemented in software without changing the underlying display hardware. For example, an alpha display layer, which is a display layer located on top of all other display layers, can be used. This alpha display layer can contain information about which pixels should be turned off for each cycle of pixel relaxation. When a user interface image of the display content is composed (e.g., when various display layers are output for display), the alpha display layer indicates which pixels should be turned off regardless of what is to be displayed in the layer below the alpha display layer. Thus, the display content is displayed without significant impact by turning off different pixel groups. Further, each time the display content needs to be updated (e.g., when the display time is changed), the alpha display layer can switch to a different set of pixels to be turned off. Thus, excessive use of pixels can be avoided, and "ghost" images can be more appropriately prevented without the need to change the hardware of the computing device.

[0015] Referring now to the drawings, FIG. 1 shows a representation of display content 100 when different pixel groups are turned off, according to some embodiments of the present disclosure.

[0016] The first representation 105 shows an enlarged portion of the displayed content 100 with the first pixel set 110 turned off. In the first representation 105, the pixels constituting the display content 100 are divided into square units of four pixels. The first pixel set 110 can include, for example, the upper left pixel of a four-pixel square unit and the lower right pixel of a four-pixel square unit. When these pixels are turned off, the display content 100 can be displayed at a lower resolution than when all four pixels of the four-pixel square unit are turned on.

[0017] The second illustration 115 shows an enlarged portion of the display content 100 with the second pixel set 120 turned off. The second pixel set 120 may include, for example, the upper right pixel of a 4-pixel square unit and the lower left pixel of a 4-pixel square unit. When these pixels are turned off, the display content may be displayed at a lower resolution than when all 4 pixels of the 4-pixel square unit are turned on.

[0018] In some embodiments, the first pixel set 110 and the second pixel set 120 include only one pixel that is turned off, such as only one pixel of a 4-pixel square unit. Additional details regarding the selection of the two or one pixel to turn off in each of the first pixel set 110 and the second pixel set 120 are described below in connection with FIG. 3.

[0019] FIG. 2 shows a display 200 of a wearable computing device according to some embodiments of the present disclosure. Aspects of the present disclosure are contemplated for use in any computing device including a display, particularly an OLED display, but aspects of the present disclosure are particularly advantageous for mobile computing devices and wearable computing devices because the content displayed on these types of computing devices can typically be presented in a quickly accessible manner (e.g., "at a glance"). Thereby, the user can access information by viewing the content and, in some cases, can even perform actions quickly without the need to call the computing system, such as by performing a "wake-up" function that activates the computing system. This is generally achieved by operating the computing device in the AOD mode, in which the content is displayed on the display even when the user is not explicitly interacting with the computing device, particularly a wearable computing device where the interaction between the user and the device is often short and omitted. Thus, these devices spend most of their time in this AOD mode and display the same content for a long time.

[0020] The display 200 may include various information that a user of a wearable computing device may desire to access. For example, the display 200 may include the current date, the current time, the number of steps walked by the user of the wearable computing device, battery information of the wearable computing device, notification information of various software applications, setting information, weather information of the current location of the wearable computing device, display options, and the like.

[0021] FIG. 3 shows a process 300 for selecting pixels to turn off on a display of a wearable computing device according to some embodiments of the present disclosure.

[0022] As described above with respect to FIG. 1, the area of the display 100 can be subdivided into square units of four pixels, such as pixel units 305. Two different approaches can be used to control the display 100. In the first approach 310, four separate pixel groups (e.g., four groups of one pixel, each corresponding to one pixel of the pixel unit 305) can be used. In the second approach 315, two separate pixel groups (e.g., two groups of two pixels each, where the pixels within the same group are arranged diagonally to each other, such as the upper left pixel and the lower right pixel) can be used.

[0023] In the first approach 310, each of the four-pixel groups (e.g., each individual pixel of the pixel unit 305) can be turned off in sequence. For example, as shown in operation 320, the bottom-right pixel of the pixel unit 305 can be turned off first. After a period such as one minute, the bottom-right pixel of the pixel unit 305 can be turned back on, and then the bottom-left pixel of the pixel unit 305 can be turned off. This can be repeated in sequence for the top-left and top-right pixels, and then operation 320 can be repeated indefinitely, and the entire display is refreshed after four cycles. The first approach 310 is advantageous because the display can enable pixel relaxation for each of the individual pixels in sequence within the pixel unit 305 while maintaining the desired display resolution (e.g., 320 PPI).

[0024] In the second approach 315, each of the two-pixel groups can be turned off in sequence. For example, as shown in operation 325, the pixel group including the bottom-right pixel and the top-left pixel can be turned off. After a period such as one minute, the pixels of this first pixel group can be turned back on, and the other two pixels of the pixel unit 305 (e.g., the second pixel group including the top-right pixel and the bottom-left pixel of the pixel unit 305) can be turned off. Then, operation 325 can be repeated indefinitely. The second approach 315 is advantageous because although the display resolution is halved (e.g., from 320 PPI to 160 PPI), the number of refresh cycles required to refresh the entire display is less, which can save the battery life of the wearable computing device.

[0025] In either approach, the pixels are mutually exclusive within one pixel group. For example, a pixel can be assigned only to one of the four groups in the first approach 310 or one of the two groups in the second approach 320.

[0026] When a pixel turns off, the resulting perceived display luminance may be affected. For example, a display calibrated at 3 nits will be displayed at a perceived luminance of 1.5 nits if the second approach 315 (turning off two pixels at a time) is used. In some embodiments, it may be desirable for the luminance to decrease when the computing device is operating at night or in other low light conditions, or when the computing device is docked for charging.

[0027] However, in normal ambient light conditions, it may be desirable to maintain a target display luminance set by the ambient luminance. To compensate for the decrease in perceived luminance, the display luminance values of the pixels that are not currently off can be boosted. For example, given a desired luminance of 75 nits, using the first approach 310, the display luminance value of the on pixels can be boosted to 100 nits while the fourth pixel is off. Using the second approach 315, each of the two on pixels can be boosted to 150 nits while the other two pixels are off.

[0028] In some embodiments, this change in display luminance may be dynamically affected based on the external luminance detected, for example, by the ambient light sensor input. However, using only this measurement value may cause the display to be dimmer than the desired value in a given environment. Therefore, a custom lookup table can be used in the AOD mode. For example, when using the second approach 315 (two pixels are turned off per cycle), the custom lookup table needs to specify a desired luminance value that is twice that of the normal display mode (for example, if the normal operating mode requires a luminance of 50 nits, a computing device operating in AOD requires a luminance of 100 nits).

[0029] In some embodiments, both the first approach 310 and the second approach 315 may involve using an alpha layer. The alpha layer is a display layer implemented in software that can control which pixels are ultimately displayed, regardless of the signals controlling the underlying hardware of the pixels. For example, the display can be composed of multiple display layers to show different information or provide different display functions. The layers are implemented as software layers and are combined before being output for display. The alpha layer may be a display layer that converts the underlying content for display to be partially or fully transparent, which can uniformly attenuate the brightness of the resulting display and / or can be used, for example, with dither settings, to selectively display certain pixels. When the layers are composited, the alpha layer may be the final or last layer in the stack of multiple display layers, indicating which pixels (s) should be made more or less transparent and / or which pixels should be turned on or off.

[0030] In some embodiments, both the first approach 310 and the second approach 315 may involve adding a blurring step of 1 to 3 pixel widths before turning a pixel off. In particular, in the second approach 315 (where 2 out of each 4-pixel square unit are turned off in each cycle), some display content may appear to have "block noise" as the pixels are turned off. To prevent the appearance of this block noise, the blurring step can be applied to the original image being displayed (e.g., before applying a pixel-off filter). The blurring step may involve matrix operations that are performed across the entire display without knowing which pixels are to be turned off. In this way, the blurring effect diffuses the transition from on pixels to off pixels.

[0031] Figure 4 shows a chart 400 that depicts a comparison of afterimage contrast according to some embodiments of the present disclosure. Afterimage contrast is used to measure the visibility of artifacts when switching from static content to a normal user interface. The first curve 405 represents that, using the second approach 320 (where 2 pixels are turned off every cycle for every 4-pixel square unit), there is a significant reduction in afterimage contrast compared to other methods.

[0032] Figure 5 shows a method 500 for displaying content on a display of a computing device according to some embodiments of the present disclosure. In some embodiments, method 500 can be executed by one or more processors of the computing device and can be stored on a non-transitory computer-readable medium as instructions executable by one or more processors of the computing device.

[0033] At block 505, method 500 may include identifying a plurality of pixels that are displaying content on the display of the computing device. For example, if the display is currently configured to display content (such as a date, time, battery information, weather information, etc.), method 500 may include identifying the location of the displayed content and the corresponding pixels associated with that location. In some embodiments, the pixel on / off switching operation can be performed on all pixels that display content on the display, as described below. In an alternative embodiment, the pixel on / off switching operation can be performed on only a subset of the pixels that display content.

[0034] At block 510, method 500 may include dividing the identified pixels into a subset of at least two pixel groups. As previously described with respect to FIG. 3, the pixels for displaying the content can be divided into square units of four pixels. However, in other embodiments, the pixels can be divided into groups or units of other sizes and / or shapes. Each of these square units of four pixels can then be subdivided into two or more pixel groups. In one embodiment, each square unit of four pixels is divided into four pixel groups, i.e., one for each pixel within the square unit of four pixels. In different embodiments, each square unit of four pixels is divided into two pixel groups. That is, one includes the upper left and lower right pixels of the square unit of four pixels, and the other includes the upper right and lower left pixels of the square unit of four pixels.

[0035] In any of the embodiments, the pixels of each square unit of four pixels are then grouped into larger pixel groups. For example, in a first embodiment, each upper left pixel of each square unit of four pixels can be grouped into a first plurality of pixels (a "pixel group"). In another example, in a second embodiment, each pair of identified pixels (e.g., the upper left pixel and the lower right pixel) of each square unit of four pixels can be grouped into a first pixel group. In the first embodiment, this grouping results in four pixel groups corresponding to the positions of the pixels of each square unit of four pixels. In the second embodiment, this grouping results in two pixel groups corresponding to the two sets of paired pixels of each square unit of four pixels.

[0036] At block 512, method 500 may include alternately activating and deactivating the identified subset of pixel groups from block 510. For example, method 500 may include "circulating" through turning off each pixel group in turn while turning on all the remaining pixel groups and then turning off each pixel group in turn. Additional details regarding the alternating activation and deactivation of pixel groups are described below in connection with FIG. 6.

[0037] Figure 6 shows a method 513 for alternately activating and deactivating pixel subsets on a display of a computing device, according to some embodiments of the present disclosure. In some embodiments, method 513 can be executed by one or more processors of a computing device and can be stored on a non-transitory computer-readable medium as instructions executable by one or more processors of the computing device.

[0038] At block 515, method 513 can include determining whether the display of the computing device is operating in AOD mode. This can be done, for example, by checking one or more settings in memory to determine whether the display of the computing device is currently in AOD mode.

[0039] If the computing device is not in AOD mode (No at block 515), method 513 can end (block 520). In this case, the computing device can be in a normal display mode and thus can turn off the display after a set period (user-defined or otherwise) or can manage the display of content on the display of the computing device in other ways.

[0040] If the computing device is in AOD mode (Yes at block 515), method 513 can include turning off a first pixel group of the plurality of pixel groups identified at block 510 (at block 525). For example, in a first embodiment, method 513 can include turning off all pixels of a first plurality of pixels corresponding to the bottom left pixel of each 4-pixel square unit. In a different example, in a second embodiment, method 513 can include turning off all pixels of a first plurality of pixels corresponding to one matching pixel pair (e.g., the top left pixel and the bottom right pixel) of each 4-pixel square unit.

[0041] In some embodiments, method 513 can implement an alpha display layer that includes information indicating individual pixels that are turned off when a first pixel group is turned off. Next, this alpha display layer can be used to turn off the indicated pixels by identifying the positions of the pixels to be turned off with respect to the pixel power supply and activation logic of the computing device. Thereafter, this alpha display layer can be regenerated for each new pixel group and / or when the display content is updated.

[0042] At block 530, method 513 may include waiting for a certain period of time while the first pixel group is turned off. In some embodiments, this period may be one minute. This period allows the turned-off pixels to "rest" completely and not display content, thereby increasing the lifespan of the pixels until the display content is "burned in" to the pixels.

[0043] At block 535, method 513 may include turning the pixels of the first pixel group back on. This can be performed by identifying which pixels should be turned back on from the alpha display layer and providing instructions for these pixels to the pixel power supply and activation logic of the computing device.

[0044] At block 540, method 513 may include turning off a second pixel group of the plurality of pixel groups identified at block 510. For example, in a first embodiment, method 513 may include turning off all pixels of a second pixel group corresponding to the upper left pixel of each four-pixel square unit. In a different example, in a second embodiment, method 513 may include turning off all pixels of a second pixel group corresponding to one matching pixel pair (e.g., the upper right pixel and the lower left pixel) of each four-pixel square unit.

[0045] Next, method 513 can be repeated in whole or in part. For example, method 513 can then be repeated for each identified pixel group to alternately turn off and on one or two pixels out of each 4-pixel square unit. This allows the desired display content to be displayed at the desired normal resolution or at a resolution lower than normal while turning off pixels and thus sequentially relaxing them.

[0046] In some embodiments, method 513 may include adding a blurring step of 1 to 3 pixel widths before turning off the pixels. In particular, in the second approach 315 (where 2 pixels out of each 4-pixel square unit are turned off in each cycle), some display content may appear to have "block noise" because the pixels are turned off. To prevent the appearance of this block noise, a blurring step can be applied to the pixels that are on.

[0047] In some embodiments, method 513 may also include a step of brightening the pixels. When the pixels are turned off, the resulting perceived brightness of the display may be affected. For example, a display calibrated at 3 nits will be displayed with a perceived brightness of 1.5 nits when 2 pixels out of each 4-pixel square unit are turned off. In some embodiments, it may be desirable for the brightness to decrease, such as when the computing device is operating at night or in other low-light conditions, or when the computing device is docked for charging.

[0048] However, under normal ambient light conditions, it may be desirable to maintain the target display brightness set by the ambient brightness. To compensate for the perceived brightness reduction, the display brightness values of pixels that are not currently off can be boosted. For example, given a desired brightness of 75 nits and using an embodiment where one pixel is turned off per 4-pixel square unit, the display brightness values of the three on pixels can be boosted to 100 nits while the fourth pixel is off. In an embodiment where two pixels out of each 4-pixel square unit are turned off, each of the two on pixels can be boosted to 150 nits while the other two pixels are off.

[0049] In some embodiments, this change in display brightness may be dynamically affected based on, for example, the external brightness detected by the ambient light sensor input. However, using only this measurement value may cause the display to be dimmer than the desired value in a given environment. Therefore, a custom lookup table can be used for the AOD mode. For example, when two pixels are turned off per cycle, the custom lookup table needs to specify a desired brightness value that is twice that of the normal display mode (e.g., if the normal operating mode requires a brightness of 50 nits, a computing device operating in AOD requires a brightness of 100 nits).

[0050] In some embodiments, it may be desirable to increase the AOD brightness of pixels beyond the hardware limits set for the computing device. For example, in the case of a display programmed with a maximum AOD brightness of 150 nits, when one pixel out of each 4-pixel square is turned off, the perceived brightness may appear to be 112.5 nits. In another example, in the case of a display programmed with a maximum AOD brightness of 150 nits, when two pixels out of each 4-pixel square are turned off, the perceived brightness may appear to be 75 nits. Therefore, in scenarios with particularly high ambient brightness (e.g., operation of a computing device under sunlight), two different approaches can be used to compensate for and achieve the desired brightness.

[0051] In one embodiment, a hardware approach can be used. To increase the luminance of pixels using hardware, method 513 may include generating an instruction to provide an increased current to the currently-on pixels. This increase in current corresponds to the required increase in luminance needed based on the number of pixels turned off in each 4-pixel square unit. For example, when 2 out of each 4-pixel square unit are turned off, to achieve a luminance value of 150 nits, an instruction can be generated to increase the current to the on pixels as if the desired luminance of the on pixels is 300 nits.

[0052] In a second embodiment, a software approach can be used. For example, if the detected ambient lux condition exceeds 10,000, method 513 can include operating all pixels turned on for a certain period (e.g., 1 - 5 minutes), and after this duration, the "dimming effect" can be enabled by alternately turning off different pixel groups as described above. In some embodiments, this "dimming effect" can be combined with an existing pixel shift method to extend the duration of the on state of all pixels of AOD during the period, so that even if a pixel is currently on, the pixel is still relaxed.

[0053] FIG. 7 shows a wearable computing device 600 according to some embodiments of the present disclosure. As shown, the wearable computing device 700 can be worn, for example, on a user's arm 602 (e.g., wrist). For example, the wearable computing device 600 may include a band 604 and a housing 610. In some embodiments, the housing 610 may include a conductive material (e.g., metal). In an alternative embodiment, the housing 110 may include a non-conductive material (e.g., plastic material, ceramic material).

[0054] The housing 610 can be coupled to the band 604. In this way, the band 604 can be fastened around the user's arm 602 to secure the housing 610 to the user's arm 602.

[0055] In some embodiments, the wearable computing device 600 may include a display screen 612. The display screen 612 can display content (e.g., time, date, biometric authentication, etc.) for the user to view. In some embodiments, the display screen 612 may include an interactive display screen (e.g., a touch screen or a non-contact screen). In such embodiments, the user can interact with the wearable computing device 600 via the display screen 612 to control the operation of the wearable computing device 600.

[0056] In some embodiments, the wearable computing device 600 may include one or more input devices 614 that can be operated (e.g., pressed) by the user to interact with the wearable computing device 600. For example, the one or more input devices 614 may include mechanical buttons that can be operated (e.g., pressed) to interact with the wearable computing device 600. In some embodiments, the one or more input devices 614 can be operated to control the operation of a backlight (not shown) associated with the display 612. It should be understood that the one or more input devices 614 can be configured to enable the user to interact with the wearable computing device 600 in any suitable manner. For example, in some embodiments, the one or more input devices 614 can be operated by the user to navigate content (e.g., one or more menu screens) displayed on the display screen 612.

[0057] The wearable computing device 600 is shown as an exemplary computing device, but the details of the present disclosure can be contemplated to be implemented in other types of computing devices such as smart cellular phones, personal computers, tablet computers, personal digital assistants, laptop computers, and the like.

[0058] The subject matter of the present disclosure has been described in detail with respect to various specific embodiments thereof, but each example is provided for illustrative purposes and is not intended to limit the present disclosure. Those skilled in the art will understand from the foregoing that such changes, modifications, and equivalents can be readily made to such embodiments. Accordingly, the present disclosure does not exclude including such modifications, variations, and / or additions to the subject matter as will be readily apparent to those skilled in the art. For example, features illustrated or described as part of one embodiment can be used with another embodiment to produce further embodiments. Accordingly, the present disclosure is intended to include such changes, modifications, and equivalents.

Claims

1. A method for refreshing pixels of a display operating in an always-on mode, comprising: identifying a plurality of pixels of the display that are activated while the display is operating in the always-on mode; dividing the plurality of pixels into at least two pixel subsets including a first pixel subset and a second pixel subset that are mutually exclusive; alternately activating and deactivating the first pixel subset and the second pixel subset respectively.

2. Dividing the plurality of pixels into the at least two pixel subsets comprises: dividing the plurality of pixels for displaying content into units of four pixels; assigning each pixel of each unit of four pixels to one of the at least two pixel subsets. The method according to claim 1.

3. Each unit of four pixels is a 2×2 pixel unit for displaying content. The method according to claim 2.

4. The at least two pixel subsets include two pixel subsets, and assigning each pixel of each unit of four pixels to at least one of the two pixel subsets comprises: identifying two identified pixels of the unit of four pixels as pixels separated from each other diagonally in the 2×2 pixel unit; assigning the two identified pixels to one of the two pixel subsets; assigning the other two pixels of the unit of four pixels to a second subset of the two pixel subsets. The method according to claim 3.

5. The at least two pixel subsets include four pixel subsets, and assigning each pixel of each unit of four pixels to one of the four pixel subsets includes assigning each pixel of the unit of four pixels to a different pixel subset of the four pixel subsets. The method according to claim 3.

6. Alternately activating and deactivating the first pixel subset and the second pixel subset respectively comprises: turning on a second subset of the four pixel subsets; turning off a third subset of the four pixel subsets; waiting for a certain period of time; turning on the third subset of the four pixel subsets; Turning off a fourth subset of the four pixel subsets, the method according to claim 5. **Claim 7** Making the first pixel subset and the second pixel subset alternately active and inactive respectively includes Turning off at least one of the at least two pixel subsets Waiting for a certain period Turning on at least one of the at least two pixel subsets Turning off a second subset of the at least two pixel subsets, the method according to claim 1. **Claim 8** The method according to claim 1, further including increasing the brightness of one of the at least two pixel subsets currently being displayed by increasing the current provided to the pixels of the pixel subset. **Claim 9** Making the first pixel subset and the second pixel subset alternately active and inactive respectively includes Identifying which pixels of the display need to be turned off based on the pixel subset of the at least two pixel subsets Providing the identified pixels to an alpha display layer Using the alpha display layer to turn off the identified pixels, the method according to claim 1. **Claim 10** The method according to claim 1, further including performing an image blurring step before turning off one of the at least two pixel subsets. **Claim 11** A computing device comprising A display One or more processors A memory including instructions that, when executed by the one or more processors, cause the one or more processors to perform operations, the operations including Identifying a plurality of pixels of the display that are activated while the display is operating in an always-on mode Dividing the plurality of pixels into at least two pixel subsets including a first pixel subset and a second pixel subset that are mutually exclusive Making the first pixel subset and the second pixel subset alternately active and inactive respectively, a computing device. **Claim 12** Dividing the plurality of pixels into the at least two pixel subsets includes Dividing the plurality of pixels for displaying content into units of four pixels; Assigning each pixel of each four-pixel unit to one of the at least two pixel subsets, the computing device according to claim 11.

13. The computing device according to claim 12, wherein each four-pixel unit is a 2×2 pixel unit for displaying content.

14. The at least two pixel subsets include two pixel subsets, and assigning each pixel of each four-pixel unit to at least one of the two pixel subsets includes identifying two identified pixels of the four-pixel unit as pixels separated from each other diagonally in the 2×2 pixel unit; assigning the two identified pixels to one of the two pixel subsets; and assigning the other two pixels of the four-pixel unit to a second pixel subset of the two pixel subsets, the computing device according to claim 13.

15. The at least two pixel subsets include four pixel subsets, and assigning each pixel of each four-pixel unit to one of the four pixel subsets includes assigning each pixel within the four-pixel unit to a different pixel subset of the four pixel subsets, the computing device according to claim 13.

16. Alternately activating and deactivating the first pixel subset and the second pixel subset respectively includes turning on a second subset of the four pixel subsets; turning off a third subset of the four pixel subsets; waiting for a certain period; turning on the third subset of the four pixel subsets; and turning off a fourth subset of the four pixel subsets, the computing device according to claim 15.

17. Alternately activating and deactivating the first pixel subset and the second pixel subset respectively includes turning off at least one of the at least two pixel subsets; waiting for a certain period; and turning on the at least one of the at least two pixel subsets, Turning off a second pixel subset of the at least two pixel subsets, the computing device according to claim 11.

18. The operation further includes increasing the brightness of one pixel subset of the at least two currently displayed pixel subsets by increasing the current provided to the pixels of the pixel subset, the computing device according to claim 11.

19. Making the first pixel subset and the second pixel subset alternately active and inactive respectively, Identifying which pixels of the display need to be turned off based on the pixel subset of the at least two pixel subsets, Providing the identified pixels to an alpha display layer, Using the alpha display layer to turn off the identified pixels, the computing device according to claim 11.

20. The operation further includes performing an image blurring step before turning off one pixel subset of the at least two pixel subsets, the computing device according to claim 11.

Images