Backlight control circuit, electronic device and display panel driving method

Patent metadata

Field	Value
Publication number	US-2016284282-A1
Application number	US-201414413150-A
Country	US
Kind code	A1
Filing date	Jan 17, 2014
Priority date	Dec 17, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

A display panel driving method for driving a LED module of an electronic device to emit light, the method includes steps: controlling to scan a left-eye image and a right-eye image when the electronic device works at a 3D mode (S 401 ); controlling the LED module to turn off and does not emits light during a predetermined period less than a scanning time of the left-eye image or the right-eye image, after switching to scan the left-eye image and the right-eye image (S 402 ); and controlling the LED module to turn on and emit light after the predetermined period has passed (S 403 ). The present invention also provides a backlight control circuit and an electronic device, the present invention capable of controlling the backlight module to emit light via the same signal and do not cause the interference between different signals.

First claim

What is claimed is:

1 . A backlight control circuit, configured to drive a light-emitting diode (LED) module of an electronic device to emit light, comprising a time schedule controller and a LED driving unit, the time schedule controller comprising a display signal output pin, the time schedule controller outputting image signals with a first frequency to a display screen via the display signal output pin to execute a scanning for an image, thus driving the display screen to display the corresponding image, wherein, the time schedule controller further comprises a backlight control pin, the backlight control pin is connected to the LED module;
wherein, when the electronic device is worked at a three-dimensional (3D) mode, and when the time schedule controller switches scanning a left-eye image and a right-eye image, the time schedule controller controls the backlight control pin to output a backlight control signal with a first voltage to the LED module to control the LED module to turn off and does not emits light during a predetermined period less than a scanning time of the left-eye image or the right-eye image; the time schedule controller further controls the backlight control pin to output a backlight control signal with a second voltage to the LED module to control the LED module to turn on and emit light until the scanning time of the left-eye image or the right-eye image is finished, after the predetermined period has passed.

2 . The backlight control circuit of claim 1 , wherein when the electronic device works at the 3D mode, the time schedule controller controls a scanning frequency for scanning the left-eye image or the right-eye image to be a second frequency which is N times the first frequency, thus the left-eye image or the right-eye image would be scanned N times reputedly during the scanning time of the left-eye image or the right-eye image; the time schedule controller outputs the backlight control signal with the first voltage to the LED module to control the LED module to turn off and not to emit light during a period of the left-eye image or the right-eye image is scanned M times which is less than the N times, and then outputs the backlight control signal with the second voltage to the LED module to control the LED module to turn on and emit light after the left-eye image or the right-eye image has been scanned M times, until the scanning time of the left-eye image or the right-eye image is finished.

3 . The backlight control circuit of claim 1 , wherein the time schedule controller controls the scanning frequency for scanning the left-eye image or the right-eye image to be the first frequency, the time schedule controller outputs the backlight control signal with the first voltage to control the LED module to turn off and not to emit light during the predetermined period less than the scanning time, from starting scan the left-eye image or the right-eye image; the time schedule controller then outputs the backlight control signal with the second voltage to control the LED module to turn on and emit light after the left-eye image or the right-eye image has been scanned the predetermined period, until the scanning time of the left-eye image or the right-eye image is finished.

4 . The backlight control circuit of claim 1 , wherein the LED module comprises an anode input port and a plurality of LED strings connected between the anode input port and ground in parallel, each LED string comprises several LEDs and a metal oxide semiconductor field effect transistor (MOSFET) connected between the anode input port and ground in series, the backlight control pin is connected to a drain of the MOSFET of each LED string, the time schedule controller controls the backlight control pin to output the backlight control signal with the first voltage to control the MOSFET of all of the LED strings to turn off, thus the LED module does not emit light; the time schedule controller further controls the backlight control pin to output the backlight control signal with the second voltage to the MOSFET of all of the LED strings to turn on all of the LED strings, thus the LED module emits light.

5 . The backlight control circuit of claim 1 , wherein control time sequences of all of the LEDs of the LED module are the same.

6 . An electronic device, comprising a light-emitting diode (LED) module, a display screen, and a backlight control circuit, the backlight control circuit being configured to drive a light-emitting diode (LED) module of an electronic device to emit light, comprising a time schedule controller and a LED driving unit, the time schedule controller comprising a display signal output pin, the time schedule controller outputting image signals with a first frequency to a display screen via the display signal output pin to execute a scanning for an image, thus driving the display screen to display the corresponding image, wherein, the time schedule controller further comprises a backlight control pin, the backlight control pin is connected to the LED module;
wherein, when the electronic device is worked at a three-dimensional (3D) mode, and when the time schedule controller switches scanning a left-eye image and a right-eye image, the time schedule controller controls the backlight control pin to output a backlight control signal with a first voltage to the LED module to control the LED module to turn off and does not emits light during a predetermined period less than a scanning time of the left-eye image or the right-eye image; the time schedule controller further controls the backlight control pin to output a backlight control signal with a second voltage to the LED module to control the LED module to turn on and emit light until the scanning time of the left-eye image or the right-eye image is finished, after the predetermined period has passed.

7 . The electronic device of claim 6 , wherein when the electronic device works at the 3D mode, the time schedule controller controls a scanning frequency for scanning the left-eye image or the right-eye image to be a second frequency which is N times the first frequency, thus the left-eye image or the right-eye image would be scanned N times reputedly during the scanning time of the left-eye image or the right-eye image; the time schedule controller outputs the backlight control signal with the first voltage to the LED module to control the LED module to turn off and not to emit light during a period of the left-eye image or the right-eye image is scanned M times which is less than the N times, and then outputs the backlight control signal with the second voltage to the LED module to control the LED module to turn on and emit light after the left-eye image or the right-eye image has been scanned M times, until the scanning time of the left-eye image or the right-eye image is finished.

8 . The electronic device of claim 6 , wherein the time schedule controller controls the scanning frequency for scanning the left-eye image or the right-eye image to be the first frequency, the time schedule controller outputs the backlight control signal with the first voltage to control the LED module to turn off and not to emit light during the predetermined period less than the scanning time, from starting scan the left-eye image or the right-eye image; the time schedule controller then outputs the backlight control signal with the second voltage to control the LED module to turn on and emit light after the left-eye image or the right-eye image has been scanned the predetermined period, until the scanning time of the left-eye image or the right-eye image is finished.

9 . The electronic device of claim 6 , wherein the LED module comprises an anode input port and a plurality of LED strings connected between t

Assignees

• Shenzhen China Star Optoelect

Inventors

• Zhang Hua
• Zhang Xianming

Classifications

• H05B45/38

  using boost topology · CPC title

• H05B45/46

  having LEDs disposed in parallel lines · CPC title

• H05B47/155

  Coordinated control of two or more light sources · CPC title

• G09G3/342

  using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines · CPC title

• G09G2320/0209

  Crosstalk reduction, i.e. to reduce direct or indirect influences of signals directed to a certain pixel of the displayed image on other pixels of said image, inclusive of influences affecting pixels in different frames or fields or sub-images which constitute a same image, e.g. left and right images of a stereoscopic display · CPC title