The present invention relates generally to display systems. More specifically, the present invention relates to a system and method for reducing power consumption in display systems.
This section is intended to introduce the reader to various aspects of art, which may be related to various aspects of the present invention that are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Portability has become an increasingly important characteristic of display products. Display products such as laptops or mobile computers, personal digital assistants, and mobile telecommunication devices have become widespread largely due to the flexibility and convenience they provide through portability. However, obtaining portability often requires the display device to be powered by a battery source, and a short battery life may decrease the benefits of portability and usefulness of the device in general.
In portable products with relatively large screens, a relatively large portion of power needed to operate the device is consumed by the light sources that illuminate the display. Therefore, portable electronic devices with large displays running on battery power may experience a relatively limited battery life. One method of extending battery life for portable displays has been to decrease the light illumination of the display. However, this method conserves battery life at some expense to display performance. Dimmed illumination may cause difficulties in viewing because of low contrast and brightness. A more efficient method of extending battery life for portable display devices is desired.
Advantages of the invention may become apparent upon reading the following detailed description and upon reference to the drawings in which:
One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
Electronic devices powered by batteries have a useful run time determined in part by the life of the batteries. This includes portable display products such as portable LCD displays that are powered by batteries. The run time of such devices is further limited by the power required by the display. For devices with a relatively large screen size, a large percentage of the total power consumed is used to illuminate the display area. An exemplary embodiment of the present invention extends battery life in an electronic device by removing illumination from selective zones of the display area at opportunistic times (e.g., when certain portions of the display are not in use).
Backlighting systems for display devices may comprise multiple types of light sources, such as cold cathode fluorescent lamps (CCFLs) or light emitting diodes (LEDs). Such light sources may be equally and geometrically spaced across the display area such that each light source is responsible for lighting a specific portion of the display. Therefore, an electronic device may turn off a zone of the display by turning off the light sources in that zone. Thus, the illuminated area of the display is decreased, power is conserved, and the run time of the battery and the electronic device is extended.
The memory 106 may be adapted to hold machine-readable computer code that causes the processor 104 to perform an exemplary method in accordance with the present invention. The lighting control logic 110 may be adapted to receive output from the processor and control the status of the light source 112 in response thereto. The light source 112 may be adapted to illuminate the display 114, and may comprise CCFLs, LEDs, or any other light source appropriate for illuminating a display 114. Furthermore, the light source 112 may be spaced such that the processor 104 and/or the lighting control logic 110 may cause individual light sources or groups of light sources to be turned off or on to selectively illuminate only the identified image zones of the display area.
In one exemplary embodiment, the electronic device 100 may turn off illumination in display zones corresponding to a border of the image so that only the image itself is illuminated. For example, an LCD display panel displaying a wide screen movie would have borders across the top and bottom of the display. Since the borders are not part of the image, the light sources in the zones of the display area corresponding to borders may be turned off. Thus, power may be conserved without jeopardizing the quality of the image.
In another exemplary embodiment, the electronic device 100 may reduce the image size such that it occupies a smaller portion of the display area. For example, if an LCD display panel has a resolution of 1280×720, then some number of individual light sources could illuminate the entire 1280×720 pixel array. An image could likewise occupy the entire 1280×720 pixel array. However, a user may choose to decrease the size of the image, thereby decreasing the area of the illuminated display. If a user chooses to display an image at only 25% of the display size, the electronic device 100 may receive this low power user image size preference and adjust the image size responsive to the low power user image size preference request so that the adjusted image displayed by the electronic device 100 occupies an image zone that is smaller than the entire display size. In this example, the processor 104 and/or the lighting control logic 110 may reduce the image size so that rather than occupying the entire 1280×720 pixel array (921,600 pixels), the image would only occupy a 640×360 pixel array (230,400 pixels). Light sources within the image zone would be illuminated, and light sources outside the image zone would not be illuminated.
Additionally, the user may choose a customize option 208, enabling selection of the border settings, as represented by block 210; borders may either be illuminated (block 214) or not illuminated (block 212). The user may also input the display content area settings, as represented by block 216, to either select the display area as 100% of the original image size, as represented by block 218, or select the display area as a certain percentage (n %) of the original image size, as represented by block 220. Selecting n % of the original image also allows the user to select a location, as represented by block 222, on the display screen of which the n % image will appear. After choosing the content area setting and border setting, the user may then save the settings at block 224 so that the customized image display settings may be more quickly reached from the customized save settings menu option (block 226) the next time the device is in use.
At block 228, the user command is delivered to the processor 104 (
In another exemplary embodiment of the present invention, fixed choices of image sizes may also be made available to a user. For example, the electronic device 100 (
While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.
Number | Date | Country | Kind |
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200710124031.8 | Oct 2007 | CN | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US07/83200 | 10/31/2007 | WO | 00 | 3/19/2010 |