Color filters are mainly used in the field of optical display. Color filter (Colorfilter) is an optical filter that expresses color. It can select a small range of light waves to pass through, while reflecting off other undesired wave bands. The color filter is usually installed in front of the light source, so that the human eye can receive a saturated color light. There are infrared filters, green, blue, etc. Color filter is a key component of liquid crystal display (LiquidCrystalDisplay) color display. The LCD flat panel display is a non-active light-emitting component, and its color display must be provided through the internal backlight module (transmissive LCD) or external ambient incident light (reflective or semi-transmissive LCD) to provide the light source, and then with the driver IC (DriveIC) Controlled with liquid crystal (LiquidCrystal) to form a gray scale display (GrayScale), and then through the color filter R, G, B color layer to provide hue (Chromacity), forming a color display screen.