Display apparatus and control method thereof

• US 7,663,320 B2
• Filed: 06/18/2007
• Issued: 02/16/2010
• Est. Priority Date: 10/16/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Jung, Jun-ho, Kim, Hyung-rae, Choi, Hoon, Seong, Ki-bum, Sung, Jun-ho
• Primary Examiner(s): Vu; David Hung
• Application Number:
  US11/764,254
• Publication Number:
  US 20080088243A1
• Time in Patent Office: 974 Days
• Field of Search: 315/149, 315/155, 315/156, 315/157, 315/158, 315/159, 315/169.3, 315/291, 315/307, 315/308
• US Class Current: 315/156
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: H05B 45/24 using electrical feedback from LEDs or from LED modules

Abstract

A display apparatus having a displaying part on which an image is displayed, includes: a backlight unit comprising a plurality of light emitting elements that emit different color light which illuminates the displaying part, the plurality of light emitting elements being arranged in a predetermined pattern; a driving part that applies driving current to the backlight unit to control the operation of the light emitting elements and the intensity of light emitted from each of the light emitting elements; a sensing part that senses the amount of light emitted from the backlight unit; and a controller that detects a level of driving current applied to the backlight unit by the driving part, and if the detected level of driving current exceeds a predetermined reference current level, controls the driving part to adjust the backlight unit based on the amount of light sensed by the sensing part.

Claims

1. A display apparatus having a displaying part on which an image is displayed, comprising:

a backlight unit comprising a plurality of light emitting elements that emit different color lights which illuminate the displaying part, the plurality of light emitting elements being arranged in a predetermined pattern;

a driving part that applies driving currents to the backlight unit to control an operation of the plurality of light emitting elements and intensities of lights emitted from the plurality of the light emitting elements;

a sensing part that senses an amount of light emitted from the backlight unit; and

a controller that detects a level of one of the driving currents applied to the backlight unit by the driving part, and if the detected level of the one driving current exceeds a predetermined reference current level, controls the driving part to adjust the backlight unit based on the amount of light sensed by the sensing part.

2. The display apparatus according to claim 1, wherein the plurality of the light emitting elements comprise a red color light emitting diode, a green color light emitting diode, and a blue color light emitting diode, and

wherein the controller controls the driving part to adjust at least one of an intensity of light emitted from the red color light emitting diode, an intensity of light emitted from the green color light emitting diode, and an intensity of light emitted from the blue color light emitting diode, based on the amount of light that is emitted from the backlight unit and is sensed by the sensing part.

3. The display apparatus according to claim 1, wherein the controller detects a level of driving current applied to a light emitting element, which is adjacent to the sensing part, of the plurality of light emitting diodes of the backlight unit.

4. The display apparatus according to claim 3, further comprising a signal input part to which an image signal is inputted,

wherein the controller checks a gray scale of the inputted image signal and detects the level of driving current applied to the light emitting element adjacent to the sensing part, based on the checked gray scale.

5. The display apparatus according to claim 4, wherein the controller sets weights to the plurality of light emitting elements depending on distances from the sensing part, and detects the level of driving current applied to the light emitting element adjacent to the sensing part using the set weights and the gray scale for each illumination region of the backlight unit.

6. The display apparatus according to claim 1, wherein the controller sets weights to the plurality of light emitting elements depending on distances from the sensing part, and detects the level of driving current applied to the light emitting element adjacent to the sensing part using the set weights and a gray scale for each illumination region of the backlight unit.

7. The display apparatus according to claim 1, wherein, if a number of times in which the level of driving current exceeds the reference current level is more than a predetermined number, the controller controls the driving part to adjust the backlight unit.

8. The display apparatus according to claim 1, wherein, if a gray scale is less than a reference gray scale, the controller controls the driving part to maintain the level of driving current applied to the backlight unit.

17. The display apparatus according to claim 1, wherein the controller sets weights to the plurality of light emitting elements and detects the driving current using the weights and a gray scale for each illumination region of the backlight unit.

19. The display apparatus according to claim 1, wherein the level of driving current is determined by multiplying the gray scale by the weight of the light emitting element and dividing by the sum of the weights of the plurality of light emitting elements.

20. The display apparatus according to claim 1, wherein if the detected level of the driving current does not exceed a predetermined level, the controller controls the driving part to maintain the amount of light sensed by the sensing part.

9. A control method of a display apparatus having a displaying part on which an image is displayed, a backlight unit comprising a plurality of light emitting elements that emit different color lights which illuminates the displaying part, the plurality of light emitting elements being arranged in a predetermined pattern, a driving part that applies driving currents to the backlight unit to control operation of the plurality of light emitting elements and controls intensities of light emitted from the plurality of light emitting elements, and a sensing part that senses an amount of light emitted from the backlight unit, the control method comprising:

detecting a level of driving current applied to the backlight unit by the driving part;

comparing the detected level of driving current with a predetermined reference current level; and

if the detected level of driving current exceeds the predetermined reference current level, controlling the driving part to adjust the backlight unit based on the amount of light sensed by the sensing part.

10. The control method according to claim 9, wherein the plurality of light emitting elements comprise a red color light emitting diode, a green color light emitting diode, and a blue color light emitting diode, and

wherein the controlling the driving part comprises adjusting at least one of an intensity of light emitted from the red color light emitting diode, an intensity of light emitted from the green color light emitting diode, and an intensity of light emitted from the blue color light emitting diode, based on the amount of light that is emitted from the backlight unit and is sensed by the sensing part.

11. The control method according to claim 9, wherein the detecting the level of driving current comprises detecting a level of driving current applied to a light emitting element, which is adjacent to the sensing part, of the plurality of light emitting diodes of the backlight unit.

12. The control method according to claim 11, further comprising inputting an image signal,

wherein the detecting the level of driving current comprises:

checking a gray scale of the inputted image signal; and

detecting the level of driving current applied to the light emitting element adjacent to the sensing part, based on the checked gray scale.

13. The control method according to claim 12, wherein the detecting the level of driving current comprises:

setting weights to the plurality of light emitting elements depending on a distance from the sensing part; and

detecting the level of driving current applied to the light emitting element adjacent to the sensing part using the set weights and the gray scale for each illumination region of the backlight unit.

14. The control method according to claim 9, wherein the detecting the level of driving current comprises:

setting weights to the plurality of light emitting elements depending on a distance from the sensing part; and

detecting the level of driving current applied to the light emitting element adjacent to the sensing part using the set weights and a gray scale for each illumination region of the backlight unit.

15. The control method according to claim 9, wherein the controlling the driving part comprises adjusting the backlight unit if a number of times in which the level of driving current exceeds the reference current level is more than a predetermined number.

16. The control method according to claim 9, wherein the controlling the driving part comprises maintaining the level of driving current applied to the backlight unit if a gray scale is less than a reference gray scale.

18. The control method according to claim 9, wherein the detecting the level of driving current comprises detecting the driving current, and

wherein detecting the driving current comprises setting weights to at least one of the light emitting elements, and detecting the level of the driving current using the set weights and the gray scale.