Electronic device, display controlling apparatus and method thereof

• US 9,336,725 B2
• Filed: 04/09/2014
• Issued: 05/10/2016
• Est. Priority Date: 04/11/2013
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Cho, Byoungchul, Park, Sangjae
• Primary Examiner(s): Giesy, Adam R
• Application Number:
  US14/249,112
• Publication Number:
  US 20140307007A1
• Time in Patent Office: 762 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G09G 2320/0613 The adjustment depending on the type of the information to be displayed
• 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 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 2380/14 Electronic books and readers
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

There are provided an electronic device and a display controlling apparatus and method. The display controlling apparatus that is driven in a paper mode and includes a backlight includes an image processing device that first converts a gradation value of an input image so as to have image characteristics of the paper mode, and second converts the first converted gradation value of the input image so as to have a upper limit gradation value is scaled up to the maximum gradation value, and a backlight brightness determining unit that determines brightness of light irradiated by the backlight to be lowered in response to the second conversion of the gradation value.

Claims

1. A display controlling apparatus that is driven in a paper mode and includes a backlight, the display controlling apparatus comprising:

an image processing device first converting a gradation value of an input image so as to have image characteristics of the paper mode, and second converting the first converted gradation value of the input image so as to have a maximum gradation value; and

a backlight brightness determining unit determining brightness of light irradiated by the backlight to be lowered in response to the second conversion of the gradation value.

2. The display controlling apparatus of claim 1, wherein the image processing device first converts the gradation value of the input image by associating the gradation value of the input image with a lookup table.

3. The display controlling apparatus of claim 1, wherein the first conversion of the gradation value of the input image includes applying a first upper limit gradation value and a first lower limit gradation value of the paper mode.

4. The display controlling apparatus of claim 1, wherein, in the image processing device the second conversion of the gradation value is performed by applying a scaling factor to the first converted gradation value of the input image.

5. The display controlling apparatus of claim 4, wherein the scaling factor is a ratio of a second upper limit gradation value acquired from the first converted image and the maximum gradation value, and wherein the second upper limit gradation value is the highest gradation value in the first converted image.

6. The display controlling apparatus of claim 4, wherein the backlight brightness determining unit determines to lower the brightness of the backlight by applying the scaling factor to the brightness of the backlight for the input image.

7. The display controlling apparatus of claim 5, wherein the backlight brightness determining unit determines to lower the brightness of the backlight by applying the scaling factor to the brightness of the backlight for the input image.

8. The display controlling apparatus of claim 1, wherein the image characteristics of the paper mode include at least one of a color temperature, brightness, and a contrast ratio.

9. The display controlling apparatus of claim 1, wherein the gradation value of the input image includes a gradation value of each of R, G, and B colors, and the first conversion for the gradation value of the input image and the second conversion for the first converted gradation value of the image are associated with each of gradation values of the R, G, and B colors.

10. The display controlling apparatus of claim 1, wherein the image characteristics of the paper mode are image characteristics with respect to a plurality of different types of papers.

11. The display controlling apparatus of claim 1, wherein the second conversion of the image processing device is implemented by histogram stretching.

12. The display controlling apparatus of claim 11, wherein the backlight brightness determining unit determines the brightness of the backlight to be lowered in accordance with a degree to which the histogram stretching is performed.

13. An electronic device comprising:

a liquid crystal display panel displaying an image having image characteristics of a paper mode and a maximum gradation value;

a backlight irradiating the liquid crystal display panel with light;

an image processing device converting a gradation value of an input image to have the image characteristics of the paper mode and the maximum gradation value; and

a backlight control unit controlling brightness of light irradiated by the backlight to be lowered in response to the gradation conversion of the input image to have the maximum gradation value.

14. A method for displaying an image in a display apparatus including a backlight, the method comprising:

first converting a gradation value of an input image to have image characteristics of a paper mode;

second converting the first converted gradation value of the image to have a maximum gradation value;

controlling brightness of the backlight in response to the second conversion; and

displaying an image of the second converted gradation value.

15. The method of claim 14, wherein the first converting comprises associating the gradation value of the input image with a lookup table.

16. The method of claim 14, wherein the converting the gradation value of the input image to have the image characteristics of the paper mode includes applying a first upper limit gradation value and a first lower limit gradation value to the input image.

17. The method of claim 14, wherein the second converting comprises applying a scaling factor to the first converted gradation value of the image.

18. The method of claim 17, wherein the scaling factor is a ratio of a second upper limit gradation value of the first converted image and the maximum gradation value, and wherein the second upper limit gradation value is the highest gradation value in the first converted image.

19. The method of claim 17, wherein the controlling of the brightness of the backlight comprises lowering the brightness of the backlight by applying the scaling factor to the brightness of the backlight with respect to the input image.

20. The method of claim 18, wherein the controlling of the brightness of the backlight comprises lowering the brightness of the backlight by applying the scaling factor to the brightness of the backlight with respect to the input image.

21. The method of claim 14, wherein the gradation value of the input image includes a gradation value of each of R, G, and B colors, and the first converting and the second converting are associated with each of gradation values of the R, G, and B colors.