Temperature Compensation Circuit, Temperature Compensation Method and Liquid Crystal Display

Patent metadata

Field	Value
Publication number	US-2016149574-A1
Application number	US-201514600893-A
Country	US
Kind code	A1
Filing date	Jan 20, 2015
Priority date	Nov 20, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

Disclosed are a temperature compensation circuit for a display panel, a temperature compensation method and a liquid crystal display. The temperature compensation circuit comprises: a temperature detection unit configured to detect a variation in the temperature; a temperature conversion unit configured to convert the detected variation in the temperature into a voltage compensation value; and a compensation signal generation unit configured to process the voltage compensation value to generate a compensation signal. According to the embodiments of the present disclosure, the common electrode voltage of the display panel can be adjusted in real-time when the temperature varies, so that an amount of flickers presented on the display panel with an polarity inversion can be maintained at minimum, and thus a displaying of picture can be more stable and a visual experience of a viewer can be enhanced.

First claim

What is claimed is:

1 . A temperature compensation circuit for a display panel, comprising:
a temperature detection unit configured to detect a variation in a temperature; a temperature conversion unit configured to convert the detected variation in the temperature into a voltage compensation value; and a compensation signal generation unit configured to process the voltage compensation value to generate a compensation signal for performing a temperature compensation on a common electrode voltage of the display panel.

2 . The temperature compensation circuit of claim 1 , wherein the compensation signal generation unit comprises at least one of a plurality of compensation sub-units: an addition compensation sub-unit, a subtraction compensation sub-unit, a multiplication compensation sub-unit and a division compensation sub-unit.

3 . The temperature compensation circuit of claim 2 , further comprising:
a selection unit configured to select at least one of the compensation sub-units in the compensation signal generation unit to process the voltage compensation value, in order to generate the compensation signal.

4 . The temperature compensation circuit of claim 3 , further comprising:
a storage unit configured to store amounts of flicker presented on the display panel at different temperatures and corresponding common electrode voltage values; an identification unit configured to identify a function relationship between the temperature and the common electrode voltage value when the display panel presents a minimum amount of flicker based on the stored amounts of flicker at the different temperatures and the corresponding common electrode voltage values, and to output a control signal to the selection unit.

5 . The temperature compensation circuit of claim 4 , wherein the selection unit is configured to select the at least one of the plurality of compensation sub-units to generate the compensation signal according to the control signal output from the identification unit.

6 . The temperature compensation circuit of claim 5 , wherein the temperature conversion unit comprises a first operational amplifier, wherein a non-inverting input terminal of the first operational amplifier is configured to receive the variation in temperature output from the temperature detection unit, an inverting input terminal thereof is grounded via a first resistor, and an output terminal thereof is connected to the inverting input terminal thereof via a first feedback resistor and is configured to output the converted voltage compensation value.

7 . The temperature compensation circuit of claim 1 , wherein the temperature detection unit comprises a temperature sensor, wherein the temperature sensor is a thermistor and is disposed on a signal driving circuit board of the display panel to detect an external temperature of the display panel.

8 . The temperature compensation circuit of claim 1 , wherein the temperature detection unit comprises a temperature sensor, wherein the temperature sensor is made of polysilicon and is disposed at Thin Film Transistors side inside the display panel to detect an internal temperature of the display panel.

9 . The temperature compensation circuit of claim 2 , wherein the addition compensation sub-unit comprises
a second operational amplifier whose non-inverting input terminal is configured to receive the voltage compensation value and the common electrode voltage via a second resistor and a third resistor, respectively, whose inverting input terminal is grounded via a fourth resistor, and whose output terminal is connected to the inverting input terminal thereof via a second feedback resistor and is configured to output a sum of the common electrode voltage signal and the voltage compensation value as the compensation signal.

10 . The temperature compensation circuit of claim 2 , wherein the subtraction compensation sub-unit comprises:
a third operational amplifier whose non-inverting input terminal and inverting input terminal are configured to receive the common electrode voltage and the voltage compensation value via a fourth resistor and a fifth resistor, respectively, and whose output terminal is connected to the inverting input terminal thereof via a third feedback resistor and is configured to output a difference between the common electrode voltage signal and the voltage compensation value as the compensation signal.

11 . The temperature compensation circuit of claim 2 , wherein the multiplication compensation sub-unit comprises:
a fourth operational amplifier configured to perform a logarithm operation on a first signal received at its inverting input terminal and to output the same; a fifth operational amplifier configured to perform a logarithm operation on a second signal received at its inverting input terminal and to output the same; a sixth operational amplifier configured to perform an addition operation on signals output from the fourth operational amplifier and the fifth operational amplifier; and a seventh operational amplifier configured to perform an exponent operation on a signal output from the sixth operational amplifier and to output a product of the first signal and the second signal as the compensation signal.

12 . The temperature compensation circuit of claim 2 , wherein the division compensation sub-unit comprises:
an eighth operational amplifier configured to perform a logarithm operation on a first signal received at its inverting input terminal and output the same; a ninth operational amplifier configured to perform a logarithm operation on a second signal received at its inverting input terminal and output the same; a tenth operational amplifier configured to perform a subtraction operation on signals output from the eighth operational amplifier and the ninth operational amplifier; and an eleventh operational amplifier configured to perform an exponent operation on a signal output from the tenth operational amplifier in order to generate the compensation signal.

13 . A liquid crystal display comprising the temperature compensation circuit of claim 1 .

14 . A temperature compensation method for a display panel, comprising:
detecting a variation in the temperature of the display panel; converting the detected variation in the temperature into a voltage compensation value; and generating a compensation signal for performing a temperature compensation on a common electrode voltage of the display panel based on the voltage compensation value.

15 . The temperature compensation method of claim 14 , further comprises:
storing amounts of flicker of the display panel at different temperatures and corresponding common electrode voltage values; identifying a function relationship between the temperature of the display panel and the common electrode voltage value in a case of a minimum amount of flicker based on the stored amounts of flicker of the display panel at the different temperatures and the corresponding common electrode voltage values; and based on the identified function relationship, selecting a corresponding process on the voltage compensation value to generate the compensation signal.

16 . The liquid crystal display of claim 13 , wherein the compensation signal generation unit comprises at least one of a plurality of compensation sub-units: an addition compensation sub-unit, a subtraction compensation sub-unit, a multiplication compensation sub-unit and a division compensation sub-unit.

17 . The liquid crystal display of claim 16 , wherein the temperature compensation circuit furth

Assignees

• Boe Technology Group Co Ltd
• Beijing Boe Optoelectronics

Inventors

• Cui Ziwei
• Wang Luyang
• Zhao Long
• Sun Qi

Classifications

• G09G3/3655

  Details of drivers for counter electrodes, e.g. common electrodes for pixel capacitors or supplementary storage capacitors · CPC title

• G09G3/3696

  Generation of voltages supplied to electrode drivers · CPC title

• G09G2320/041

  Temperature compensation · CPC title

• H03K19/00369 Primary

  Modifications for compensating variations of temperature, supply voltage or other physical parameters · CPC title