Color gamut of tft display
The display principle of the color TFT display is to use color filters of three colors of RGB to filter the light from the backlight to form the pattern we need. The three color filters and backlight will have a great impact on the color expression ability of the display screen. The higher the color gamut, the stronger the display’s ability to express colors, and the more colorful the picture looks.
There are many ways to measure color, the two commonly used ones are SRGB and NTSC. The LCD panel industry usually uses NTSC as the standard for measurement. Due to different product positioning, the color gamut of IPS mode displays is usually higher than that of TN mode displays.
Are NTSC and sRGB the same?
NTSC was formulated by the FCC of the United States in 1953. Since it was designated earlier and the electronics industry developed very rapidly, it is not a standard color gamut. sRGB is the standard color gamut established by IEC in 1999. The color space of sRGB is smaller than NTSC, with an approximate ratio of 3:4.
TN display color gamut
IPS display color gamut
Is it possible to convert between NTSC and sRGB?
The relationship between different color spaces，Picture from BenQ
Conversion between NTSC and sRGB is possible, but the area of the color space cannot be simply calculated. For example, 72% of the NTSC color space area is the same as 100% of the sRGB area. However, their positions in CIE1931 are different, and the colors they can express are different. What we need is that the three colors of red, green and blue are more intense, not other colors. , so we can only say that their color coverage is the same.
How to improve the color gamut of tft display?
From the above discussion, we can know that there are two important factors that affect the color gamut of TFT display, one is the color filter and the other is the backlight.
Color filters are made of dyes. The more dyes used, the stronger the color expression ability, but the transmittance of the corresponding color filters will become worse, which is very fatal for tft display.
Color film spectrum
Effect of backlight on color gamut
LED spectrum
Backlight is another important factor. Most of the light generated by the backlight will be absorbed by the color filter. Only a small part will shoot out. If the spectrum of the backlight is very different from the spectrum of the color filter, the light efficiency will be very low and the color gamut will be poor. When the two spectra match well, the light efficiency and color gamut will be improved. Changing the backlight spectrum is achieved by changing the ratio of phosphors. The whole process is difficult to implement and requires a lot of time and money. If you have any needs in this regard, please contact us.
