DISPLAY DEVICE AND BRIGHTNESS CONTROL METHOD CAPABLE OF REDUCING POWER CONSUMPTION OF DISPLAY DEVICE

• US 20130169692A1
• Filed: 03/27/2012
• Published: 07/04/2013
• Est. Priority Date: 12/29/2011
• Status: Abandoned Application

• Current Assignee: HannStar Display Corporation
• Original Assignee: HannStar Display Corporation
• Inventors: Wang, Chao-Hsin
• Application Number:
  US13/430,717
• Publication Number:
  US 20130169692A1
• Time in Patent Office: Days
• US Class Current: 345/690
• CPC Class Codes: G09G 2310/066 Waveforms comprising a gently increasing or decreasing portion, e.g. ramp
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2320/064 by time modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 2320/0673 for control of gamma adjustment, e.g. selecting another gamma curve
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336

Abstract

A display device includes a display panel, a backlight module, a driving circuit and a control unit. The driving circuit is electrically connected to the backlight module and used for providing a driving voltage for the backlight module. The control unit is electrically connected to the display panel and the driving circuit. The control unit controls the driving voltage to vary within a predetermined ratio range periodically so as to make a backlight brightness of the backlight module vary periodically in response to the driving voltage within the predetermined ratio range and controls a display parameter of the display panel to vary periodically according to the backlight brightness of the backlight module so as to compensate the backlight brightness of the backlight module. Accordingly, the invention can reduce power consumption of the backlight module effectively so as to reduce power consumption of the display device.

Claims

1. A display device comprising:

a display panel;

a backlight module;

a driving circuit electrically connected to the backlight module, the driving circuit being used for providing a driving voltage for the backlight module; and

a control unit electrically connected to the display panel and the driving circuit, the control unit controlling the driving voltage to vary within a predetermined ratio range periodically so as to make a backlight brightness of the backlight module vary periodically in response to the driving voltage within the predetermined ratio range and controlling a display parameter of the display panel to vary periodically according to the backlight brightness of the backlight module so as to compensate the backlight brightness of the backlight module.

2. The display device of claim 1, wherein the control unit controls the driving voltage to decrease from an upper bound of the predetermined ratio range to a lower bound of the predetermined ratio range and then controls the driving voltage to increase from the lower bound of the predetermined ratio range to the upper bound of the predetermined ratio range during each cycle.

3. The display device of claim 2, wherein the upper bound of the predetermined ratio range is 100% and the lower bound of the predetermined ratio range is 80%.

4. The display device of claim 2, wherein a period of each cycle is larger than or equal to one minute.

5. The display device of claim 1, wherein the display parameter comprises brightness, contrast, gamma value or combination thereof.

6. A brightness control method capable of reducing power consumption of a display device, the display device comprising a display panel and a backlight module, the brightness control method comprising:

controlling a driving voltage of the backlight module to vary within a predetermined ratio range periodically so as to make a backlight brightness of the backlight module vary periodically in response to the driving voltage within the predetermined ratio range; and

controlling a display parameter of the display panel to vary periodically according to the backlight brightness of the backlight module so as to compensate the backlight brightness of the backlight module.

7. The brightness control method of claim 6 further comprising:

first controlling the driving voltage of the backlight module to decrease from an upper bound of the predetermined ratio range to a lower bound of the predetermined ratio range and then controlling the driving voltage to increase from the lower bound of the predetermined ratio range to the upper bound of the predetermined ratio range during each cycle.

8. The brightness control method of claim 7, wherein the upper bound of the predetermined ratio range is 100% and the lower bound of the predetermined ratio range is 80%.

9. The brightness control method of claim 7, wherein a period of each cycle is larger than or equal to one minute.

10. The brightness control method of claim 6, wherein the display parameter comprises brightness, contrast, gamma value or combination thereof.