Display apparatus and method of controlling the same

• US 20070081357A1
• Filed: 10/02/2006
• Published: 04/12/2007
• Est. Priority Date: 10/12/2005
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Sung-soo, Park, Yung-jun, Sung, Jun-ho
• Application Number:
  US11/540,598
• Publication Number:
  US 20070081357A1
• Time in Patent Office: Days
• US Class Current: 362/561
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133613 characterized by the sequence of light sources
• CPC Class Codes: G09G 2310/024 Scrolling of light from the illumination source over the display in combination with the scanning of the display screen
• CPC Class Codes: G09G 2310/061 for resetting or blanking
• CPC Class Codes: G09G 2320/064 by time modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• 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 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A display apparatus having a liquid crystal panel, comprises a light source part comprising a plurality of point light sources for supplying light to the liquid crystal panel. The light source part is partitioned into a plurality of light source zones. A light source driving part supplies power to the light source part. A plurality of channel parts sense luminescence of the point light sources for each of the light source zones and output light-emission information of the point light sources based on the sensed luminescence. A controller compares the light-emission information output from the plurality of channel parts with a pre-set reference value. If a difference between the light-emission information and the reference value is out of a predetermined allowable range, the controller sequentially adjusts PWM control signals which are output to the light source driving part, for each of the light source zones.

Claims

1. A display apparatus having a liquid crystal panel, comprising:

a light source part comprising a plurality of point light sources for supplying light to the liquid crystal panel, the light source part being partitioned into a plurality of light source zones;

a light source driving part for supplying power to the light source part;

a plurality of channel parts for sensing luminescence of the point light sources for each of the light source zones and outputting light-emission information of the point light sources based on the sensed luminescence; and

a controller for comparing the light-emission information output from the plurality of channel parts with a pre-set reference value, and, sequentially adjusting PWM control signals if a difference between the light-emission information and the reference value is out of a predetermined allowable range, which control signals are output to the light source driving part, for each of the light source zones.

2. The display apparatus according to claim 1, wherein the light-emission information is white color coordinates of the point light-emitting sources.

3. The display apparatus according to claim 2, wherein each of the plurality of channel parts comprises:

a sensor for sensing luminescence of light emitted from the point light sources; and

a color coordinate calculator for calculating the white color coordinates of the point light sources based on the luminescence sensed by the sensor.

4. The display apparatus according to claim 1, further comprising a PWM delay part for delaying the PWM control signals output from the controller according to a predetermined synchronization signal.

5. The display apparatus according to claim 1, wherein the reference value is a color temperature value and/or a particular region on a gray axis.

6. A method of controlling a display apparatus comprising a liquid crystal panel, and a light source part comprising a plurality of point light sources for supplying light to the liquid crystal panel, the light source part being partitioned into a plurality of light source zones, the method comprising:

sensing luminescence of the point light sources for each of the light source zones;

outputting light-emission information of the light source zones based on the sensed luminescence;

comparing the output light-emission information with a pre-set reference value and sequentially adjusting PWM control signals if the difference between the output and the pre-set reference value is out of a predetermined allowable range, which control signals are output to the light source part, for each of the light source zones; and

delaying the PWM control signals according to a predetermined synchronization signal.

7. The method according to claim 6, wherein the light-emission information is white color coordinates of the point light-emitting sources.

8. The method according to claim 7, further comprising calculating the white color coordinates of the point light sources based on the sensed luminescence.

9. The method according to claim 6, wherein the reference value is a color temperature value and/or a particular region on a gray axis.

10. A computer readable medium of instructions for controlling a display apparatus comprising a liquid crystal panel and a light source part comprising a plurality of point light sources for supplying light to the liquid crystal panel, the light source part being partitioned into a plurality of light source zones, comprising:

a first set of instructions adapted to control the apparatus to sense luminescence of the point light sources for each of the light source zones;

a second set of instructions adapted to control the apparatus to output light-emission information of the light source zones based on the sensed luminescence;

a third set of instructions adapted to control the apparatus to compare the output light-emission information with a pre-set reference value and to sequentially adjust PWM control signals if the difference between the output and the pre-set reference value is out of a predetermined range; and

a fourth set of instructions adapted to control the apparatus to delay the PWM control signals according to a predetermined synchronization signal.

11. A display apparatus having a liquid crystal panel, comprising:

a light source part comprising a plurality of point light sources for supplying light to the liquid crystal panel, the light source part being partitioned into a plurality of light source zones;

a light source driving part for supplying power to the light source part; and

a controller for sequentially adjusting PWM control signals, which control signals are output to the light source driving part, for each of the light source zones.

12. The display apparatus according to claim 11, further comprising a plurality of channel parts for sensing luminescence of the point light sources for each of the light source zones and outputting light-emission information of the point light sources based on the sensed luminescence,

wherein the controller compares the light-emission information output from the plurality of channel parts with a pre-set reference value, and, adjusts PWM control signals if a difference between the light-emission information and the reference value is out of a predetermined allowable range.

13. The display apparatus according to claim 12, wherein each of the plurality of channel parts comprises:

a sensor for sensing luminescence of light emitted from the point light sources; and

a color coordinate calculator for calculating the white color coordinates of the point light sources based on the luminescence sensed by the sensor.

14. The display apparatus according to claim 11, further comprising a PWM delay part for delaying the PWM control signals output from the controller according to a predetermined synchronization signal.