DEVICE AND METHOD FOR REDUCING POWER CONSUMPTION IN DISPLAY DEVICES

• US 20140125690A1
• Filed: 10/28/2013
• Published: 05/08/2014
• Est. Priority Date: 11/07/2012
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: KANZAKI, EISUKE, NAKAYAMA, YASUTOMO D.
• Granted Patent: US 9,691,334 B2
• Time in Patent Office: Days
• US Class Current: 345/600
• CPC Class Codes: G09G 2320/0271 Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping
• CPC Class Codes: G09G 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 2370/027 Arrangements and methods specific for the display of internet documents
• CPC Class Codes: G09G 2370/042 for monitor identification
• CPC Class Codes: G09G 3/36 using liquid crystals
• CPC Class Codes: G09G 5/02 characterised by the way in which colour is displayed details of colour display specific for CRTs G09G1/28; specific for flat matrix panels other than liquid crystal displays G09G3/2003; specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 5/10 Intensity circuits

Abstract

Devices and methods are disclosed that reduce the amount of power consumed by an existing display device irrespective of the display mode. One such method includes recognizing a display mode related to light and dark when no voltage is applied to the display device. The method also includes determining a shift direction for the values of an image based on the recognized display mode so that power consumption is reduced in the display device. The method further includes determining a shift amount for the values of the image in accordance with a predetermined process, and converting the values of the image to be converted in the determined shift direction in accordance with the determined shift amount.

Claims

1. A device for reducing power consumption in a display device, the device comprising:

a recognizing unit for recognizing a display mode related to light and dark when no voltage is applied to the display device;

a shift direction determining unit for determining a shift direction for the values of an image based on the display mode recognized by the recognizing unit so that power consumption is reduced in the display device;

a shift amount determining unit for determining a shift amount for the values of the image in accordance with a predetermined process; and

a converting unit for converting the values of the image to be converted in the shift direction determined by the first determining unit in accordance with the shift amount determined by the second determining unit.

2. The device of claim 1, wherein the shift direction determining unit determines that the shift direction is in the direction in which the image becomes brighter in response to the recognizing unit recognizing a first mode in which the screen is light when no voltage is applied, and determines that the shift direction is in the direction in which the image becomes darker in response to the recognizing unit recognizing a second mode in which the screen is dark when no voltage is applied.

3. The device of claim 2, wherein the converting unit converts the values of the image to be converted by changing the settings of the cascading style sheet (CSS) used by the image to be converted.

4. The device of claim 2, wherein the shift amount determining unit determines the shift amount based on a user operation that specifies the allowable level related to change in appearance of the image.

5. The device of claim 2, wherein the shift amount determining unit determines the shift amount based on the values of the image to be converted.

6. The device of claim 2, wherein the shift amount determining unit determines the shift amount for each value of the image to be converted based on a user operation that specifies the allowable level for each value of the image related to change in appearance of the image.

7. The device of claim 1, wherein the converting unit converts the values of the image to be converted by changing the settings of the cascading style sheet (CSS) used by the image to be converted.

8. The device of claim 7, wherein the shift amount determining unit determines the shift amount based on a user operation that specifies the allowable level related to change in appearance of the image.

9. The device of claim 7, wherein the shift amount determining unit determines the shift amount based on the values of the image to be converted.

10. The device of claim 7, wherein the shift amount determining unit determines the shift amount for each value of the image to be converted based on a user operation that specifies the allowable level for each value of the image related to change in appearance of the image.

11. The device of claim 1, wherein the shift amount determining unit determines the shift amount based on a user operation that specifies the allowable level related to change in appearance of the image.

12. The device of claim 1, wherein the shift amount determining unit determines the shift amount for each value of the image to be converted based on a user operation that specifies the allowable level for each value of the image related to change in appearance of the image.

13. A device for reducing power consumption in a display device, the device comprising:

a determining unit for determining whether a display mode of the display device is a normally white mode or a normally black mode;

a shift direction determining unit for determining that a shift direction for the density of an image is in the direction of lower density in response to the determining unit determining the display mode is the normally white mode, and determining that the shift direction for the density of the image is in the direction of higher density in response to the determining unit determines the display mode is the normally black mode;

an acquiring unit for acquiring association information for associating a range of the density of the image with an allowable level related to change in appearance of the image based on a user operation that specifies the allowable level for each image density range;

a calculating unit for calculating the density of the image to be converted by determining the average values of an R value, G value and B value in the image to be converted;

a shift amount determining unit for determining a shift amount for the density of the image to be converted based on the allowable level associated by the association information with a range including the density of the image to be converted as calculated by the calculating unit; and

a converting unit for converting the density of the image to be converted in the shift direction determined by the shift direction determining unit and by the shift amount determined by the shift direction determining unit, by changing the settings related to the colors in the cascading style sheet (CSS) used by the image to be converted.

14. A method for reducing power consumption in a display device, the method comprising:

recognizing a display mode related to light and dark when no voltage is applied to the display device;

determining a shift direction for the values of an image based on the recognized display mode so that power consumption is reduced in the display device;

determining a shift amount for the values of the image in accordance with a predetermined process; and

converting the values of the image to be converted in the determined shift direction in accordance with the determined shift amount.