CN101320545A - Temperature compensating device used for display - Google Patents

Abstract

In order to solve the deflection problem of the gamma curve of a display caused by temperature change, the present invention provides a temperature compensation device which is used in a display for compensating the gamma curve of the display. The temperature compensation device comprises a temperature sensor, a storage unit and a temperature compensation unit. The temperature sensor is used for detecting the environmental temperature in the display; the storage unit is used for storing a plurality of numerical data; the temperature compensation unit is coupled with the temperature sensor and the storage unit, selects a numerical datum from a plurality of numerical data according to the environmental temperature detected by the temperature sensor, and transforms an original image datum into a compensation image datum through the selected numerical datum.

Description

The temperature compensation means that is used for display

Technical field

The present invention relates to a kind of circuit arrangement that is used for a display, relate in particular to a kind of temperature compensation means that is used for a display, in order to a gamma curve according to this display of ambient temperature compensation.

Background technology

That LCD has is in light weight, power consumption is few and advantage such as low radiation, therefore be widely used in multiple on the market portable information product, for example mobile computer (notebook) and personal digital assistant (personal digital assistant, PDA) etc.The principle of work of LCD is to convert outer video signal to digital signal earlier, to carry out Flame Image Process, as Gamma correction, adjust image effects such as picture size, aberration, then convert digital signal to analog voltage signal again after, deliver to panel with the driving liquid crystal molecule.With regard to Gamma correction, the panel of display is generally measured the gamma curve characteristic of its panel in advance at the Shi Douhui that dispatches from the factory, so that the design of driving circuit in the display.

Please refer to Fig. 1, Fig. 1 is the synoptic diagram of a known display 10.Display 10 comprises time schedule controller 12, one source pole driver 14 and a panel 16, and its principle of work is as follows.Except producing clock signal Controlling Source driver 14, time schedule controller 12 also can be done after simple image handles raw digital image data SDATA1, and output digital image data SDATA2 is to source electrode driver 14.A digital to analog converter 18 converts Digital Image Data SDATA2 to voltage signal VDATA according to reference voltage V1～Vn-1 in the source electrode driver 14, and exports the light peneration of panel 16 with the control liquid crystal to.In general, before panel 16 dispatches from the factory, can measure the brightness that panel 16 is reflected in advance under different GTGs, its brightness is tied to form a curve to the pass of GTG, is called gamma curve.In order to make output image undistorted, by setting the resistance value of resistance R 1～Rn, display 10 carries out Gamma correction in the Digital Image Data transfer process.Resistance R 1～Rn produces corresponding reference voltage V1～Vn-1 after dividing potential drop, the convertible in view of the above voltage signal VDATA that goes out to meet the gamma curve of panel 16 of digital to analog converter 18.

Yet the measuring process of panel 16 is not considered the factor of temperature, makes its gamma curve be only applicable to a certain temperature conditions among a small circle.If when environment temperature significantly changes (as seasonal variations), the resistance characteristic of resistance R 1～Rn will change thereupon, cause partial pressure value misalignment (reference voltage V1～Vn-1).In addition, the penetrability of liquid crystal molecule also can change along with temperature variation, and influence penetrates the light quantity of liquid crystal molecule, causes the GTG brightness that shows and expects differently, and then causes image fault.As from the foregoing, the environment that can't adaptive temperature significantly changes of known display 10.

Summary of the invention

Fundamental purpose of the present invention is to provide a kind of temperature compensation means that is used for a display, to solve the gamma curve skew that makes this display because of temperature variation, causes the problem of image fault.

The present invention discloses a kind of temperature compensation means that is used for a display, in order to compensate a gamma curve of this display.This temperature compensation means includes a temperature sensor, a storage element and a temperature compensation unit.This temperature sensor is used for detecting an environment temperature of this display interior.This storage element is used for storing many stroke counts Value Data.This temperature compensation unit is coupled to this temperature sensor and this storage element, and this environment temperature that is used for detecting according to this temperature sensor, from this many stroke counts Value Data, select a numeric data, and, change a raw image data and become a compensating image data by selected this numeric data.

The present invention also discloses a kind of temperature compensation that is used for compensating a gamma curve of a display.This temperature compensation includes: store the storage element of many stroke counts Value Data in this display; Detect an environment temperature of this display interior; According to this environment temperature that this temperature sensor detected, from this many stroke counts Value Data, select a numeric data; By selected this numeric data, change a raw image data and become a compensating image data.

Description of drawings

Fig. 1 is the synoptic diagram of a known display.

Fig. 2 is the synoptic diagram of one embodiment of the invention display.

Fig. 3 is the synoptic diagram according to Fig. 2 one temperature compensation means.

Fig. 4 is the synoptic diagram according to the gamma curve of a panel under different temperatures of Fig. 2 display.

Fig. 5 is the synoptic diagram of compensation work principle of the temperature compensation unit of Fig. 3.

Fig. 6 is the process flow diagram of a temperature compensation flow process of one embodiment of the invention.

The reference numeral explanation

10,20 displays

12,210 time schedule controllers

14,220 source electrode drivers

16,230 panels

18 digital to analog converters

The SDATA2 Digital Image Data

V1～Vn-1 reference voltage

R1～Rn resistance

The VDATA voltage signal

200 temperature compensation means

310 temperature sensors

320 storage elements

330 temperature compensation units

The SDATA1 raw digital image data

The CDATA compensating image data

60 flow processs

W0, W15, W25, W35, A, B, C gamma curve

600,602,604,606,608,610 steps

Embodiment

Please refer to Fig. 2, Fig. 2 is the synoptic diagram of one embodiment of the invention display 20.Display 20 can be according to temperature variation, and moderately image data processing is with the shown gamma characteristic of compensating images, and it includes a receiving end IN, a temperature compensation means 200, time schedule controller 210, one source pole driver 220 and a panel 230.Time schedule controller 12, source electrode driver 14 and panel 16 are identical among the framework of time schedule controller 210, source electrode driver 220 and panel 230 and function mode and Fig. 1, do not give unnecessary details at this.Temperature compensation means 200 can be arranged at before the time schedule controller 210 of display 20, anticipate raw digital image data SDATA1 after, export to time schedule controller 210 again; Also or, temperature compensation means 200 is arranged between time schedule controller 210 and the source electrode driver 220, processes digital image data SDATA2 delivers to source electrode driver 220 again.For ease of explanation the present invention, in Fig. 2, temperature compensation means 200 is arranged at before the time schedule controller 210, and in order to the raw digital image data SDATA1 of compensation from receiving end IN reception, and raw digital image data SDATA1 is generally red, green, blue (R, G, B) view data.

Please continue with reference to figure 3, Fig. 3 is the synoptic diagram of temperature compensation means 200 among Fig. 2.Temperature compensation means 200 is used for compensating a gamma curve of display 20, and it includes a temperature sensor 310, a storage element 320 and a temperature compensation unit 330.Temperature sensor 310 is used for detecting an environment temperature of display 20 inside.Storage element 320 is used for storing many stroke counts Value Data.Temperature compensation unit 330 is coupled to temperature sensor 310 and storage element 320, and is used for the environment temperature that detected according to temperature sensor 310, selects a numeric data in storage element 320 many stroke counts Value Datas.Then, temperature compensation unit 330 can be according to an equation, and by selected numeric data, conversion raw digital image data SDATA1 becomes a compensating image data CDATA.This equational output goes into to concern as follows:

$\left[\begin{array}{c}{R}^{\′}\\ G^{\′}\\ B^{\′}\end{array}\right]=\left[\begin{array}{ccc}R1& G1& B1\\ R2& G2& B2\\ R3& G3& B3\end{array}\right]\left[\begin{array}{c}R\\ G\\ B\end{array}\right]+\left[\begin{array}{c}\mathrm{rc}\\ \mathrm{gc}\\ \mathrm{bc}\end{array}\right]...\left(1\right)$

Wherein, $\left[\begin{array}{c}R\\ G\\ B\end{array}\right]$ Be raw digital image data SDATA1; $\left[\begin{array}{c}{R}^{\′}\\ G^{\′}\\ B^{\′}\end{array}\right]$ Be compensating image data CDATA; $\left[\begin{array}{ccc}R1& G1& B1\\ R2& G2& B2\\ R3& G3& B3\end{array}\right]$ And $\left[\begin{array}{c}\mathrm{rc}\\ \mathrm{gc}\\ \mathrm{bc}\end{array}\right]$ It then is selected numeric data of coming out from storage element 320.

In storage element 320, many stroke counts Value Data of storage can be obtained by following method.At first, under different temperature, obtain the gamma curve of different gamma values via a panel of actual measurement display 20.Please refer to Fig. 4, Fig. 4 is the synoptic diagram of gamma curve W1, W15, W25 and the W35 of panel under different temperatures of display 20 of the present invention.Wherein, transverse axis is a GTG value 0～255, and the longitudinal axis is regular brightness, and it is worth between 0～1, and 0,15,25 and 35 ℃ of corresponding environment temperatures of gamma curve W0, W15, W25 and W35, the gamma value of its curve is respectively 1.96,2.11,2.20 and 2.30.At this, the panel 230 of supposing display 20 works in gamma curve W25 when dispatching from the factory.Then, according to the relation between curve and the curve, promptly the relation between gamma curve W0 and W25, W15 and W25, W35 and the W25 calculates each group matrix function Value Data.In brief, can obtain the numeric data of each non-preset temperature from Fig. 4.

Please refer to Fig. 5, Fig. 5 is the synoptic diagram of compensation work principle of the temperature compensation unit 230 of Fig. 3.Fig. 5 is similar to Fig. 4, and it is the synoptic diagram of gamma curve A, B, C.Gamma curve A is the panel 230 of display 20 preset working curve when dispatching from the factory, as the gamma curve W25 of Fig. 4.If because of variation of ambient temperature, the gamma curve of panel is offset to gamma curve C (for example being offset to W35 by gamma curve W25) by gamma curve A.After display 20 starts, can detect the environment temperature of corresponding gamma curve C via temperature sensor 310, and temperature compensation unit 330 can select one group of matrix function Value Data (for example aforesaid from storage element 320 according to testing result $\left[\begin{array}{ccc}R1& G1& B1\\ R2& G2& B2\\ R3& G3& B3\end{array}\right]$ And $\left[\begin{array}{c}\mathrm{rc}\\ \mathrm{gc}\\ \mathrm{bc}\end{array}\right]$ ), its data are (as gamma curve W15 and the W25) that produce according to the relation between gamma curve A and the B.Via the conversion of equation (1), compensating image data CDATA corresponds to gamma curve B, and just equation (1) converts the view data that has the gamma curve A characteristic originally to gamma curve B characteristic view data.Thus, when compensating image data CDATA exports panel to, because the characteristic of panel is gamma curve C, the display characteristic of panel will return back to gamma curve A, and then display frame can reach original display effect, and is not subjected to influence of temperature change.

Please refer to Fig. 6, Fig. 6 is the process flow diagram of a temperature compensation flow process 60 of one embodiment of the invention.Temperature compensation flow process 60 is used for cooperating temperature compensation means 200, and with the gamma curve of panel 230 of compensation display 20, it comprises the following step:

Step 600: beginning.

Step 602: store the storage element 230 of many stroke counts Value Data in display 20.

Step 604 a: environment temperature that detects display 20 inside.

Step 606:, from this many stroke counts Value Data, select a numeric data S1 according to this environment temperature that is detected.

Step 608: by numeric data S1, conversion raw digital image data SDATA1 becomes compensating image data CDATA.

Step 610: finish.

According to flow process 60, the present invention is according to the environment temperature in the display, adjusts the view data of desire output, so that can not lose original gamma characteristic during the panel display image.Suppose that storages in the storage element 230 of display 20 have gamma curve D, E and the F of gamma value Γ 1, Γ 2, Γ 3 (Γ 1＞Γ 2＞Γ 3) respectively, and gamma curve E is the gamma curve that the panel 230 of display 20 dispatches from the factory.If be offset to F because of temperature variation causes the gamma curve of panel, and via selecting numeric data S1 after the temperature detection, its content shape is the matrix data of equation (1) as the aforementioned $\left[\begin{array}{ccc}R1& G1& B1\\ R2& G2& B2\\ R3& G3& B3\end{array}\right]$ And $\left[\begin{array}{c}\mathrm{rc}\\ \mathrm{gc}\\ \mathrm{bc}\end{array}\right].$ And, converting raw digital image data SDATA1 to compensating image data CDATA by equation (1), the gamma characteristic that makes compensating image data CDATA is corresponding to gamma curve D.That is to say that if the gamma curve (gamma curve F) of the extremely low gamma value (Γ 3) of panel curve offset, then conversion image data SDATA1 is corresponding to the gamma curve (gamma curve D) of higher gamma value (Γ 1).Vice versa, and as if the gamma curve (gamma curve D) of panel curve offset to higher gamma value (Γ 1), then conversion image data SDATA1 is corresponding to the gamma curve (gamma curve F) of low gamma value (Γ 3).Thus, the Gamrat performance of panel is kept the display characteristic when dispatching from the factory, and can not cause the picture distortion because of temperature variation.

In sum, temperature compensation means of the present invention comes the compensating digits view data according to environment temperature, remedying the reference voltage misalignment, and defectives such as liquid crystal molecule penetrability change, to keep the original display characteristic of panel, not influenced because of temperature variation.Therefore, temperature compensation means of the present invention is applicable to the environment that temperature significantly changes by display.

The above only is preferred embodiment of the present invention, and all equalizations of doing according to claim of the present invention change and modify, and all should belong to covering scope of the present invention.

Claims (11)

1. temperature compensation means that is used for a display, in order to compensate a gamma curve of this display, this temperature compensation means includes:

One temperature sensor is used for detecting an environment temperature of this display interior;

One storage element is used for storing many stroke counts Value Data; And

One temperature compensation unit, be coupled to this temperature sensor and this storage element, this environment temperature that is used for detecting according to this temperature sensor is selected a numeric data from this many stroke counts Value Data, and, change a raw image data and become a compensating image data by selected this numeric data.

2. temperature compensation means as claimed in claim 1, wherein this temperature compensation unit, is changed this raw image data and is become this compensating image data by selected this numeric data according to an equation.

3. temperature compensation means as claimed in claim 2, wherein this equation is:

A＝(B·C)+D；

Wherein, matrix A is this compensating image data, and Matrix C is this raw image data, and matrix B and D are selected this numeric data.

4. temperature compensation that is used for compensating a gamma curve of a display includes:

Store the storage element of many stroke counts Value Data in this display;

Detect an environment temperature of this display interior;

According to this environment temperature that is detected, from this many stroke counts Value Data, select a numeric data; And

By selected this numeric data, change a raw image data and become a compensating image data.

5. temperature compensation means as claimed in claim 4, wherein changing this raw image data by selected this numeric data, to become this compensating image data be according to an equation, by selected this numeric data, change this raw image data and become this compensating image data.

6. temperature compensation means as claimed in claim 5, wherein this equation is:

A＝(B·C)+D；

Wherein, matrix A is this compensating image data, and Matrix C is this raw image data, and matrix B and D are selected this numeric data.

7. display in order to compensate a gamma curve according to temperature variation, includes:

One receiving end is used for receiving video signals;

Time schedule controller is used for the data that receive are carried out Flame Image Process, to produce one first view data;

The one source pole driver is used for the data that receive are carried out Flame Image Process, to produce a voltage signal;

One panel is coupled to this source electrode driver, is used for receiving this voltage signal, with the display image picture; And

One temperature compensation means is used for compensating a gamma curve, includes:

One temperature sensor is used for detecting an environment temperature of this display interior;

One storage element is used for storing many stroke counts Value Data; And

One temperature compensation unit, be coupled to this temperature sensor and this storage element, this environment temperature that is used for detecting according to this temperature sensor is selected a numeric data from this many stroke counts Value Data, and, change a raw image data and become a compensating image data by selected this numeric data.

8. display as claimed in claim 7, wherein this temperature compensation means is coupled between this receiving end and this time schedule controller.

9. display as claimed in claim 7, wherein this temperature compensation means is coupled between this time schedule controller and this source electrode driver.

10. display as claimed in claim 7, wherein this temperature compensation unit, is changed this raw image data and is become this compensating image data by selected this numeric data according to an equation.

11. display as claimed in claim 10, wherein this equation is:

A＝(B·C)+D；

Wherein, matrix A is this compensating image data, and Matrix C is this raw image data, and matrix B and D are selected this numeric data.

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