MOBILE TERMINAL AND METHOD OF CONTROLLING THE SAME

• US 20120281027A1
• Filed: 04/26/2012
• Published: 11/08/2012
• Est. Priority Date: 05/02/2011
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Taeyun
• Granted Patent: US 8,872,757 B2
• Time in Patent Office: Days
• US Class Current: 345/690
• CPC Class Codes: G09G 2320/062 Adjustment of illumination source parameters
• CPC Class Codes: G09G 2320/064 by time modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2340/06 Colour space transformation
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336

Abstract

Disclosed are a mobile terminal and a method of controlling a mobile terminal. A different backlight dimming algorithm can be applied according to an application, and a dimming algorithm is selectively applied in association with an input image during executing of a specific application.

Claims

1. A mobile terminal, comprising:

a liquid crystal display panel configured to display information;

a backlight unit configured to emit backlight to the liquid crystal display panel; and

a controller configured to;

select a dimming algorithm from among a plurality of dimming algorithms based on a specific application of at least one application;

execute the specific application;

control luminance of the backlight unit based on the selected dimming algorithm; and

control luminance of the backlight unit based on a different dimming algorithm from the selected dimming algorithm when an image having a luminance value outside a preset reference range is displayed on the liquid crystal display panel during the execution of the specific application.

2. The mobile terminal of claim 1, further comprising:

a memory configured to store a database, wherein the database defines a matching relationship between each application of the at least one application and at least one dimming algorithm of the plurality of dimming algorithms,

wherein selecting the dimming algorithm comprises referencing the database.

3. The mobile terminal of claim 2, wherein the matching relationship for each application is defined based on preset criteria comprising importance of image quality or a degree of power saving.

4. The mobile terminal of claim 2, wherein the controller is configured to:

download the specific application from a source outside the mobile terminal;

install the specific application;

acquire information regarding image quality characteristics of the specific application;

select the dimming algorithm based on the acquired information;

match the selected dimming algorithm with the specific application; and

store the selected dimming algorithm for the specific application in the database.

5. The mobile terminal of claim 4, wherein acquiring the information regarding the image quality characteristics comprises receiving information while downloading the specific application or while scanning an image frame of a specific screen included in the specific application.

6. The mobile terminal of claim 4, wherein the controller is configured to:

provide a user interface configured to acquire the information regarding image quality characteristics during the installation of the specific application; and

acquire the information via the user interface.

7. The mobile terminal of claim 1, wherein the controller is further configured to:

convert a first screen providing the specific application to a second screen, which is different from the first screen, when the image having the luminance value outside the preset reference range is displayed on the liquid crystal display panel; and

control the liquid crystal display panel to display the image having the luminance value outside the preset reference range on the second screen.

8. The mobile terminal of claim 1, wherein the controller is further configured to:

insert specific contents into a first screen provided by the specific application when the image having the luminance value outside the preset reference range is displayed on the liquid crystal display panel; and

control the liquid crystal display panel to display the image having the luminance value outside the preset reference range on the first screen.

9. The mobile terminal of claim 1, wherein:

the plurality of dimming algorithms comprises a first dimming algorithm, the first dimming algorithm configured to;

detect a maximum luminance of a first frame image from an input image;

lower luminance of the backlight by an amount equal to the maximum luminance; and

up-convert pixel data included in the input image; and

the up-converted pixel data compensates for the lowered luminance of the backlight.

10. The mobile terminal of claim 9, wherein:

the plurality of dimming algorithms comprises a second dimming algorithm, the second dimming algorithm configured to;

calculate an average picture level (APL) of the first frame image from the input image;

lower luminance of the backlight by an amount equal to luminance of the APL;

up-convert pixel data included in the input image; and

write the pixel data in the liquid crystal display panel,

wherein writing the pixel data in the liquid crystal display panel compensates for the lowered luminance of the backlight.

11. The mobile terminal of claim 10, wherein the plurality of dimming algorithms comprises a third dimming algorithm, the third dimming algorithm configured to:

calculate the APL of the first frame image from the input image;

lower luminance of the backlight by the amount equal to the luminance of the APL;

separate a luminance value and a chrominance value from each other in each of at least one pixel data of the input image;

up-convert only the luminance value of the separated luminance and chrominance values;

up-convert the pixel data in terms of gamma characteristics;

calculate the pixel data with the up-converted luminance value and an original chrominance value; and

write the calculated pixel data in the liquid crystal display panel.

12. The mobile terminal of claim 11, wherein the controller is further configured to:

detect the maximum luminance of the first frame image from the input image;

execute the first dimming algorithm when the maximum luminance is less than or equal to a preset maximum luminance reference value; and

execute the second dimming algorithm or the third dimming algorithm when the maximum luminance is greater than the preset maximum luminance reference value.

13. A method of controlling a mobile terminal, the method comprising:

receiving a selection of a specific application of at least one application;

executing the specific application;

selecting, via a controller of the mobile terminal, a dimming algorithm from among a plurality of dimming algorithms based on the specific application;

emitting backlight, via a backlight unit of the mobile terminal, to a liquid crystal display panel of the mobile terminal;

controlling luminance of the backlight unit via the controller based on the selected dimming algorithm; and

controlling luminance of the backlight unit based on a different dimming algorithm from the selected dimming algorithm when an image having a luminance value outside a preset reference range is displayed on the liquid crystal display panel during the execution of the specific application.

14. The method of claim 13, further comprising:

defining, via a database, a matching relationship between each application of the at least one application and at least one dimming algorithm of the plurality of dimming algorithms; and

storing the database in a memory of the mobile terminal,

wherein selecting the dimming algorithm comprises referencing the database.

15. The method of claim 14, wherein the matching relationship for each application is defined based on preset criteria comprising importance of image quality or a degree of power saving.

16. The method of claim 14, further comprising:

downloading the specific application from a source outside the mobile terminal via the controller;

installing the specific application via the controller;

acquiring information regarding image quality characteristics of the specific application via the controller;

selecting the dimming algorithm based on the acquired information via the controller;

matching the selected dimming algorithm with the specific application via the controller; and

storing the selected dimming algorithm for the specific application in the database.

17. The method of claim 16, wherein acquiring the information regarding the image quality characteristics comprises:

receiving information, via the controller, while downloading the specific application or while scanning an image frame of a specific screen included in the specific application.

18. The method of claim 16, further comprising:

providing, via the controller, a user interface configured to acquire the information regarding image quality characteristics during the installation of the specific application; and

acquiring the information via the user interface.

19. The method of claim 13, wherein:

the plurality of dimming algorithms comprises a first dimming algorithm, the first dimming algorithm configured to;

detect a maximum luminance of a first frame image from an input image;

lower luminance of the backlight by an amount equal to the maximum luminance; and

up-convert pixel data included in the input image; and

the up-converted pixel data compensates for the lowered luminance of the backlight.

20. The method of claim 19, wherein:

the plurality of dimming algorithms comprises a second dimming algorithm, the second dimming algorithm configured to;

calculate an average picture level (APL) of the first frame image from the input image;

lower luminance of the backlight by an amount equal to luminance of the APL;

up-convert pixel data included in the input image; and

write the pixel data in the liquid crystal display panel,

wherein writing the pixel data in the liquid crystal display panel compensates for the lowered luminance of the backlight.

21. The method of claim 20, wherein the plurality of dimming algorithms comprises a third dimming algorithm, the third dimming algorithm configured to:

calculate the APL of the first frame image from the input image;

lower luminance of the backlight by the amount equal to the luminance of the APL;

separate a luminance value and a chrominance value from each other in each of at least one pixel data of the input image;

up-convert only the luminance value of the separated luminance and chrominance values;

up-convert the pixel data in terms of gamma characteristics;

calculate the pixel data with the up-converted luminance value and an original chrominance value; and

write the calculated pixel data in the liquid crystal display panel.

22. The method of claim 21, further comprising:

detecting the maximum luminance of the first frame image from the input image via the controller;

executing the first dimming algorithm, via the controller, when the maximum luminance is less than or equal to a preset maximum luminance reference value; and

executing the second dimming algorithm or the third dimming algorithm, via the controller, when the maximum luminance is greater than the preset maximum luminance reference value.