CN1763808A

CN1763808A - Image display device color temperature correction device and method

Info

Publication number: CN1763808A
Application number: CN200410050619.XA
Authority: CN
Inventors: 安秉洙
Original assignee: LG Electronics Shenyang Inc
Current assignee: LG Electronics Nanjing Plasma Co Ltd
Priority date: 2004-10-20
Filing date: 2004-10-20
Publication date: 2006-04-26

Abstract

The invention discloses an image display equipment color temperature augmenting device and method, which is characterized by the following: the display mode of R, G and B unit displays image information; the accumulator stores the brilliance level according to the lightness of R, G and B unit; the microprocessor compares the read image lightness average value of display mode with the preset first and second value to obtain the result, which controls the corrected R unit and B unit; the scaler receives the brilliance level of accumulator and forms new checking chart to main certain color temperature according to the microprocessor control signal. The invention can display premium quality image effect, which is fit for self-luminous product of big color coordinate variation.

Description

Image display colour temperature compensating device and method thereof

Technical field

The present invention relates to a kind of image display, relate in particular to a kind of colour temperature compensating device and method thereof of image display.Use in the various display modules on the image display of PDP (plasma display) module,, can guarantee to form certain color reproduction according to picture brightness revisal colour temperature.

Background technology

Usually be protection module on plasma display PDP, the average brightness of the picture signal that utilization is imported is regulated the brightness of picture.This method adopts automatic peak-limitation APL (Auto PeakLimit) loop, and it is the loop that utilizes picture brightness mean value, controls the high-high brightness of picture.

Its control method of simple declaration is as follows: the image bright to integral body, because its APL value is high, institute is so that its high-high brightness deepening; To picture on the whole is dark image, makes high-high brightness in the picture reach the high-high brightness of module, to keep certain mean flow rate.

This control method is to utilize the value of APL to understand fully overall brightness information, regulates lasting pulse (Sustain Pulse) number of decision brightness with this information.Such as, the APL value and pulse (SustainPulse) number that continues are pressed inverse relation control, continuing to exist repeatedly between pulse (Sustain Pulse) number and the picture brightness funtcional relationship rather than linear function relation this moment, is difficult so know correct result.This is the existing shortcoming of the method.

On the other hand, the product of existing use plasma display PDP module in the feature brightness according to the best test figure of think, has a function decision to pass to red R, green G, the picture signal size of blue B pixel.The degree of tilt of adjusting this function reaches the colour temperature of adjusting product, but owing to continue existing repeatedly function characteristic between pulse (Sustain Pulse) number and the picture brightness, can both reach to all brightness that to keep certain colour temperature be impossible.

The characteristic of present employed PDP module is, in case reduce brightness, just reduces the brightness of module shape light body B earlier, and R reduces the brightness of G at last then, so the colour temperature of picture diminishes, and color sensation also is partial to green.

In contrast, in case the brightness of picture brightens, just strengthen the brightness of R and B, so colour temperature just uprises, and color sensation also turns green.

Summary of the invention

The present invention its objective is a kind of image display colour temperature compensating device and the method thereof that can keep certain color temperature according to picture brightness that provide for the problem that overcomes above-mentioned existence proposes.

Be the image display colour temperature compensating device of the present invention that achieves the above object and propose, by forming with the lower part: for displays image information, by red R, green G, the display module that blue B forms each unit; Possess in the image display device of this display module, according to above-mentioned red R, green G, the brightness of each unit of blue B stores the storer of its luminance levels; The picture brightness mean value that reads above-mentioned display module is automatic peak-limitation APL data, compares with first and second definite value of having set, and controls the microprocessor of revisal above-mentioned red R unit and blue B unit colour temperature according to its result; According to above-mentioned microprocessor control signal, receive the luminance levels of storing in the above-mentioned storer and form new looking into, and keep the scaler of certain color temperature with this with table.

Above-mentioned first definite value of having set is the minimum of above-mentioned picture brightness mean value and the warning value of intermediate value, and second definite value is the intermediate value of above-mentioned picture brightness mean value and the warning value of mxm..

Above-mentioned display module is a plasma display.

Be the image display colour temperature correction method of the present invention that achieves the above object and propose, by forming: possess in the image display of storer, scaler and display module the stage that compares by the picture brightness mean value of above-mentioned display module and first and second definite value of having set with the next stage; According to above-mentioned comparative result, adopt suitable luminance levels to come the stage of revisal colour temperature in the luminance levels that above-mentioned storer is stored.

The above-mentioned stage that picture brightness mean value and first and second definite value of having set are compared is: judge that above-mentioned picture brightness mean value is whether below first definite value of having set, or between first definite value of having set and second definite value, or the deterministic process more than second definite value of having set.

The stage of above-mentioned revisal colour temperature comprises the following stage: if above-mentioned picture brightness mean value is below first definite value of having set, with regard to the luminance levels that increases red R, green G unit brightness and the stage of decline colour temperature; If above-mentioned picture brightness mean value is between first definite value of having set and second definite value, the stage of just keeping the white balance of having set; If picture brightness mean value is more than second definite value of having set, then reduce red R, the luminance levels of green G unit brightness and stage of improving colour temperature.

Image display colour temperature compensating device of the present invention and method thereof have following several effect:

The first, the mandatory of revisal conventional art reduces brightness to cause the chromaticity coordinates migration, therefore can keep certain image quality forever.

The second, also be applicable to the product that uses chromaticity coordinates to change self photism device greatly.So can embody more excellent image quality.

The 3rd, irrelevant with the input signal rank, reduce in module the poor of the color reproduction of performance by different way according to overall brightness, so can keep certain characteristic.This just there is no need additional other annexes also can guarantee colour temperature, is more effective.

Description of drawings

Below, be described in more detail as follows with reference to accompanying drawing to image display colour temperature compensating device of the present invention and method thereof.

Fig. 1 is the block diagram of image display colour temperature compensating device of the present invention.

Fig. 2 is by picture brightness presentation video signal and briliancy graph of a relation.

Fig. 3 is the process flow diagram of image display colour temperature correction method of the present invention.

The explanation of major part symbol among the figure:

101: display module 102: microprocessor

103: storer 104: scaler

104a: look into exerciser with table LUT

Embodiment

Fig. 1 is the block diagram of image display colour temperature compensating device of the present invention, and Fig. 2 is by picture mean flow rate presentation video signal value and brightness variation relation figure, and Fig. 3 is the process flow diagram of image display colour temperature correction method of the present invention.

Image display colour temperature compensating device of the present invention is as shown in Figure 1: display module 101; The picture brightness mean value that reads above-mentioned display module is automatic peak-limitation APL data, (T2) compares with first and second definite value (T1) of having set, and controls the microprocessor 102 of brightness according to its relation; Be storage R, G, the storer 103 of the luminance levels of each unit brightness of B; According to above-mentioned microprocessor 102 control signals, form the usefulness of looking into table (LUT) of looking into by the brightness adjusted value of storing in the above-mentioned storer 103 and show exerciser 104a, possess the scaler 104 of exerciser.

Above-mentioned according to APL picture signal and brightness relationship as shown in Figure 2.That is the brightness of picture signal when Fig. 2 (a) represents APL value low (that is, 1/25 window scheme does not limit the scope of picture brightness together automatically), the brightness of picture signal during Fig. 2 (b) expression APL value high (the same maximum constraints scope of flooding white mode).

At this moment, shown in Fig. 2 (a), to the dark picture image of integral body, the high-high brightness signal that exists, owing to do not carry out the process of forcing to reduce brightness, so the brightness maximal value of picture signal is exported maximum briliancy to picture, shown in Fig. 2 (b), as the whole bright images of white all over the screen, the high-high brightness signal of existence, maximum brightness is subjected to mandatory restriction and becomes mean flow rate.

In addition, though do not illustrate, the intermediate range of APL is Fig. 2 (a) and 2 (b) intermediary, and the limited degree of brightness also is the low value of APL and the intermediate value between the high value.Like this restricted the time, the brightness of R, G, each unit of B, different according to luminance levels, thereby produce color temperature difference and the whole color sensation of picture is changed.

The course of work of image display colour temperature compensating device of the present invention is described as follows.

Above-mentioned microprocessor 102 reads 10 bits (bit) picture brightness mean value from above-mentioned display module 101, and according to exporting control signal with first definite value (T1) of having stored and second definite value (T2) comparative result.

Here, above-mentioned first definite value (T1) is the warning value of above-mentioned picture brightness mean value minimum and intermediate value, promptly represents the residing start range of picture brightness mean value, and above-mentioned second definite value is represented the intermediate value and the peaked warning value of picture brightness mean value.

Thereby, the above-mentioned picture brightness mean value of importing be the APL value when first definite value of having set (T1) is following, i.e. colour temperature many scopes that rises are so improve the luminance levels of red R, the green G unit brightness colour temperature that descends in this scope.

In addition, above-mentioned APL value is kept present white balance value between first definite value of having set (T1) and second definite value (T2) time.At last, above-mentioned APL value because colour temperature descends, improves colour temperature so reduce the luminance levels of red R, green G unit brightness when second definite value (T2) is above.

The as above image display colour temperature correction method of the present invention of Gou Chenging is described as follows with reference to Fig. 3: at first, receive the power-on order just from display module, import later on the APL value (S101～S102).

Then, judge the above-mentioned APL value of importing, whether below first definite value of having set (T1) (S103).

Then, according to above-mentioned S103 judged result, below first definite value of having set (T1), the luminance levels that then improves red R, green G unit brightness reduces colour temperature (S104) as if above-mentioned APL value.

Reconstitute according to the luminance levels of the red R that improved, green G unit brightness then and look into table (LUT), and according to the colour temperature that resets, display image signals (S105～S106).

On the other hand, according to above-mentioned judged result (S103), if above-mentioned APL value when first definite value (T1) is above, judges whether below second definite value of having set (T2) (S107) again.

According to above-mentioned judged result (S107), if above-mentioned APL value between first definite value of having set (T1) and second definite value (T2), is then kept the white balance value (S108) that now has been set.

And come display image signals (S109) according to the colour temperature that the above-mentioned value of keeping is set.

In addition, according to above-mentioned judged result (S107), more than second definite value of having set (T2), the luminance levels that then reduces red R, green G unit brightness improves colour temperature (S110) as if above-mentioned APL value.

And reconstitute according to the luminance levels of lowered red R, green G unit brightness and to look into table (LUT), and according to the colour temperature that resets, display image signals (S111～S112).

In sum, image display colour temperature compensating device of the present invention and method thereof, be the APL data that from display module, read 10 bits (Bit), according to microprocessor on the result that compares of the value that has been set, from storer, read the suitable tilt adjustments R, the G value that have been stored, in route marker, constitute new looking into table.Owing to come display frame according to looking into of reconstituting, so just can keep certain colour temperature forever with the value of table.

Claims

1. An image display device color temperature correction device is characterized in that it consists of the following parts: in order to display image information, a display module consisting of red, green, and blue units; according to the brightness of the above-mentioned red, green, and blue units, store its Luminance level memory; read the average value of the screen brightness of the above-mentioned display module, that is, the automatic peak limit data, compare it with the set first and second fixed values, and control and correct the above-mentioned red unit and green unit according to the result The microprocessor of color temperature; according to the control signal of the microprocessor, the luminance level stored in the memory is received and a new look-up table is formed to maintain a certain color temperature.

2. The image display device color temperature correction device according to claim 1, characterized in that said display module is a plasma display.

3. The color temperature correction device for an image display device according to claim 1, characterized in that said first set value is a warning value between the minimum value and the middle value of the average value of the screen brightness, and the second set value is It is the warning value of the middle value and the highest value of the average value of the screen brightness above.

4. A color temperature correction method for an image display device, characterized in that it is composed of the following stages: in the image display device with a memory, a converter and a display module, the display module compares the average value of the screen brightness with the set first and the stage of comparing the second fixed value;

Based on the comparison result, the color temperature is corrected using an appropriate luminance level among the luminance levels stored in the memory.

5. The method for correcting the color temperature of an image display device according to claim 4, wherein the stage of comparing the average value of the screen brightness with the set first and second fixed values is:

It is judged whether the average value of the screen brightness is below the set first fixed value, or between the set first fixed value and the second set value, or above the set second fixed value.

6. The method for correcting the color temperature of an image display device according to claim 4, wherein the stage of correcting the color temperature comprises the following stages:

If the average brightness of the above screen is below the set first fixed value, the brightness level of the red and green unit brightness will be increased and the color temperature will be lowered;

If the average value of the screen brightness is between the set first fixed value and the second set value, the set white balance stage is maintained;

If the average value of the screen brightness is above the set second fixed value, the brightness level of the red and green unit brightness is reduced to increase the color temperature.