CN101866636A - A field color gamut liquid crystal display - Google Patents

Abstract

The invention provides a field color gamut liquid crystal display, which comprises a backlight source, wherein the backlight source consists of three light emitting diodes which sequentially emit red light, green light and blue light, and the brightness of the backlight source is determined by looking up a table of a current liquid crystal signal and a liquid crystal signal of a previous picture when a red sub-picture, a green sub-picture and a blue sub-picture are displayed. The field color gamut liquid crystal display provided by the invention is adopted to look up the current liquid crystal signal and the liquid crystal signal of the previous picture, and then the product of the original backlight signal and the current liquid crystal signal is divided by the search result in the look-up table to obtain the corrected backlight signal, so that the color error or color cast phenomenon caused by the insufficient liquid crystal reaction speed is eliminated by changing the brightness of the backlight source.

Description

A field color gamut liquid crystal display

technical field

The invention relates to a driving technology of a liquid crystal display, in particular to a brightness compensation technology of a backlight source in a field color gamut liquid crystal display.

Background technique

Field Sequential Color Liquid Crystal Display (FSC-LCD) is an ultra-thin liquid crystal display with high resolution and high color saturation. Its principle is to display red, green and blue in sequence. The screen, through the persistence of vision of the human eye, uses the time-mixing method to accumulate the three primary colors on the retina to synthesize and present a color image. Because the display does not need to use color filters, it greatly improves the light transmittance, reduces power consumption and manufacturing costs. In addition, the field color gamut liquid crystal display greatly increases the pixel aperture ratio to improve the resolution and color of the displayed image. saturation.

On the other hand, although the field color gamut liquid crystal display has better color rendering characteristics and can greatly reduce power loss, there is also a serious problem-color break-up (CBU, Color Break-Up). This phenomenon often occurs when there is a relative speed between the human eye and the viewing object. For example, when the human eye shakes or the screen moves, each color gamut of the same screen is imaged at different positions on the retina, resulting in rainbow-like ribbons on the edge of the object. The CBU phenomenon not only degrades the image quality, but even causes eye fatigue when watching for a long time.

In view of this, how to design a novel field color gamut liquid crystal display to solve and eliminate color errors when the display displays images is a problem faced by relevant technical personnel.

Contents of the invention

Aiming at the above-mentioned defects in the prior art field color gamut liquid crystal display when displaying images, the present invention provides a brand new field color gamut liquid crystal display. Cause color errors and improve the user's viewing experience.

According to one aspect of the present invention, a field color gamut liquid crystal display is provided, which includes a backlight source composed of three light-emitting diodes that sequentially emit red light, green light, and blue light, and when displaying red sub- screen, green sub-screen and blue sub-screen, the brightness of the backlight is determined by looking up the current LCD signal and the LCD signal of the previous screen.

Preferably, the current liquid crystal signal is divided by the look-up table result, and then multiplied by the original backlight signal to obtain the current backlight signal of the backlight source.

Preferably, the field color gamut liquid crystal display is a field color gamut thin film transistor liquid crystal display.

Preferably, the brightness of the image seen by human eyes on the liquid crystal display is the product of the brightness of the backlight and the light transmittance of the liquid crystal.

With the field color gamut liquid crystal display of the present invention, the current liquid crystal signal and the liquid crystal signal of the previous screen are looked up in a table, and then the product of the original backlight signal and the current liquid crystal signal is divided by the lookup result in the lookup table to obtain the corrected Backlight signal, so that by changing the brightness of the backlight to eliminate the color error or color cast caused by the liquid crystal response speed is not fast enough.

Description of drawings

Readers will have a clearer understanding of various aspects of the present invention after reading the detailed description of the present invention with reference to the accompanying drawings. in,

FIG. 1 shows a schematic diagram of the principle of using the liquid crystal signal look-up table of two adjacent frames to compensate the backlight signal of the backlight source according to the field color gamut liquid crystal display of the present invention.

Detailed ways

The specific implementation manners of the present invention will be described in further detail below with reference to the accompanying drawings.

In the prior art, in order to solve the color separation phenomenon produced by the FSC-LCD, a stencil algorithm is proposed. As far as the traditional field color gamut liquid crystal display is concerned, when there is a relative speed between the human eye and the image, it will be seen that the three color fields of red (R), green (G) and blue (B) are staggered on the retina to form a For this reason, the main focus of the Stencil algorithm is to try to reduce the light intensity of the R, G, and B three color fields, so as to reduce the intensity of the color bands pulled out due to staggering on the retina, so as to suppress color separation. At the same time, in order to maintain the original image, another color field is inserted to display the main intensity and rough color of the overall image. The original R, G, and B three color fields only need to display lower light intensity to display the correct color. image content.

More specifically, the backlight module is locally controlled to obtain the liquid crystal signals of the R, G, and B color fields and the backlight signal respectively, and the minimum value of the R, G, and B liquid crystal signal values is taken as the liquid crystal signal of the first color field, and matched with other Color backlight forms the first color screen of the Stencil type FSC-LCD. The liquid crystal signal of the second color field is the original red liquid crystal signal minus the minimum liquid crystal signal. With red backlight distribution, it becomes a red sub-color field picture, and so on, green And the blue sub-color field also knows its color picture through this calculus process.

However, it needs to be pointed out that in the design process of the current stencil algorithm, the response speed of the liquid crystal is regarded as an ideal situation, that is, the response time of the liquid crystal is close to zero, but in the actual situation, the response speed of the liquid crystal is Limited, and cannot achieve the ideal infinite speed. In this way, for example, the sky in the second frame of FSC-LCD should have a low gray level, but limited by the high gray level of the sky in the previous frame, the LCD cannot reach the target gray level in a sub-frame , the sky will have too much red to show the correct color (like blue).

Aiming at the above-mentioned shortcomings of the Stencil algorithm, FIG. 1 shows a schematic diagram of the principle of using the liquid crystal signal look-up table of two adjacent frames to compensate the backlight signal of the backlight in the field color gamut liquid crystal display according to the present invention. Referring to FIG. 1 , in general, the main principle is to correct the original backlight signal of the backlight source, and to characterize the current backlight signal as a function of the original backlight signal through a specific mathematical model.

As shown in Figure 1, assuming that the resolution of the screen is 1920*1080, and the backlight partition of the backlight is 24*24, firstly, the current liquid crystal signal 203 and the previous liquid crystal signal 201 are sent to the look-up table 205, preferably, the look-up table 205 is a color palette in the display, and the search result 207 is obtained by looking up the table. Next, the current liquid crystal signal 203 is divided by the search result 207, and based on the proportional relationship between the screen resolution and the backlight partition, the divided result is averaged to obtain the correction coefficient of the backlight signal in each backlight partition . Finally, the original backlight signal 10 is multiplied by the correction coefficient, and the resulting product is used as the current backlight signal 30 .

With the field color gamut liquid crystal display of the present invention, the current liquid crystal signal and the liquid crystal signal of the previous screen are looked up in a table, and then the product of the original backlight signal and the current liquid crystal signal is divided by the lookup result in the lookup table to obtain the corrected Backlight signal, so that by changing the brightness of the backlight to eliminate the color error or color cast caused by the liquid crystal response speed is not fast enough.

Hereinbefore, specific embodiments of the present invention have been described with reference to the accompanying drawings. However, those skilled in the art can understand that without departing from the spirit and scope of the present invention, various changes and substitutions can be made to the specific embodiments of the present invention. These changes and substitutions all fall within the scope defined by the claims of the present invention.

Claims (4)

1. A field color gamut LCD comprises a backlight source, which is characterized in that the backlight source is composed of three light emitting diodes which sequentially emit red light, green light and blue light, and when a red sub-picture, a green sub-picture and a blue sub-picture are displayed, the brightness of the backlight source is determined by the current liquid crystal signal and the liquid crystal signal of the previous picture by looking up a table.

2. The liquid crystal display of claim 1, wherein the current liquid crystal signal is divided by the look-up table result and multiplied by the original backlight signal to obtain the current backlight signal of the backlight source.

3. The gamut liquid crystal display according to claim 1, wherein the gamut liquid crystal display is a gamut thin film transistor liquid crystal display.

4. The field color gamut liquid crystal display according to claim 1, wherein the brightness of an image viewed by the human eye from the liquid crystal display is a multiplication of the brightness of the backlight source and the light transmittance of the liquid crystal.

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