LEDs have uniform problems include brightness aspect and color aspect, which would reduce the image quality of LED display. This paper gives a method to correct the color gamut of LED display. The method can solve the uniform problems, while correct the color gamut of LED display accurately, This paper establishes a liner mathematical model of LED display’colors , analyzing the target color gamut of LED display, Then, the correction method with the target color gamut as LED displays’color gamut is introduced, Furthermore,white balance in color gamut correction method is introduced to fix the color coordinates of colors accurately,Experimental results showed that this method can correct the color gamut of LED display into target color gamut accurately.
The LED display is made up of display pixels arranged in array, which has the advantages of high brightness, wide color gamut and high reliability. Has been widely used in various places of image display, when the drive current, temperature change; LED luminous intensity and wavelength will change so that the color gamut is not stable, therefore, the gray level control system of full color LED display mostly single base color by using the method of pulse width modulation PWM, by controlling the pulse width control light time LED, realize the gray level display, while the red, green and blue light LED is regarded as the three color LED display screen. The combination of three primary colors with different gray levels makes up all the colors that can be displayed by the LED display, and forms the color gamut of the LED display.
The luminance characteristic of LED has a certain discreteness. Under the existing process conditions, even if the same batch of LED chip products, the brightness difference can be controlled within 30%, and the wavelength difference can be controlled within 510nm. The tolerance value of human eye to brightness difference value is 5%, and the tolerance value of the main wavelength distribution difference is 12nm. Therefore, when the LED screen displays the same gray level, there is a certain difference between the brightness and chromaticity of the pixels. When the difference reaches a certain extent, the visual perception of the human eye on the quality of LED display will decline sharply. In addition, along with the technical level and the market demand unceasing development, the high uniformity, the high fidelity and so on a series of related visual sense application demand, has proposed the brand-new request to the LED display color ability. In order to make up for the discrete defects of LED and meet more application requirements, the brightness and chrominance correction system has been applied in the control system of LED screen. At present, brightness correction technology has been widely used in engineering production, has been able to better solve the LED bright
Uneven degree has been widely used in LED screen which requires high display quality, such as stage background, commercial advertisement and so on. However, the research of LED gamut is focused on the areas of color fidelity and gamut range. Color correction technology is only a few companies and research and development institutions at home and abroad in the study, has achieved some results. It has been used in some display screens. The existing color correction system uses measurement data as the processing object. Most of them focus on displaying the same primary color, reducing the color difference between the display pixels. It does not require the precise color coordinates of red, green and blue primary colors of the LED display screen, and a few correction systems with three primary colors for accurate color coordinate correction capabilities. Three. It is difficult to determine the display gamut of LED display at the same time without considering the accuracy of the three primary colors and the accuracy of the white field color sitting standard. The gamut correction is based on the former two, while correcting the three primary color coordinates and the white field color coordinates of the LED, which is the basis for the standardization of the LED display effect and the guarantee of color fidelity.