The use of the backlight light guide plate composition
Jan 19, 2022
The composition of the backlight light guide plate:
It is mainly composed of light source, light guide plate, optical film, plastic frame, etc. The backlight has the characteristics of high brightness, long life and uniform light emission. At present, there are mainly three types of backlight sources: EL, CCFL and LED, which can be divided into edge type and direct type according to the distribution position of the light source. With the continuous development of LCD modules to be brighter, lighter and thinner, edge-lit CCFL backlights have become the mainstream of backlight development.
Backlight backlighting is suitable for small reflective LCD applications such as watches, digital desk clocks and monochrome PDAs that require extremely low lighting for use in dim or dim conditions. However, low efficiency, low brightness, and short lifetime make it unsuitable for transmissive back lighting applications such as the large LCDs required for laptop and flat-panel desktop monitors.
The backlight light guide plate has a longer service life than EL (more than 5000 hours), and uses DC voltage, and is usually used in small monochrome displays, such as telephones, remote controls, microwave ovens, air conditioners, instrumentation, stereo audio equipment, etc. However, it is currently not bright enough to provide a backside light source for large transmissive displays. LED backlight and CCFL backlight are basically the same in structure, the main difference is that LED is a point light source, while CCFL is a line light source.
0 Compact Cold Cathode Fluorescent Lamps (CCFLs) provide the brightness and longevity (and light control capability) required for large LCDs, which is why it is still the most common method for backlighting light guides today. However, heat build-up is a concern.
The function of the backlight light guide plate is to guide the scattering direction of light, which is used to improve the brightness of the panel and ensure the uniformity of the panel brightness. Design and production is one of the key technologies. The light guide plate is made by pressing acrylic into a plate with a smooth surface by means of injection molding, and then using a material with high reflection and no light absorption to print diffusion points on the bottom surface of the light guide plate by screen printing, and the cold cathode fluorescent lamp is located on the light guide plate. At the thick end of the side, the light emitted by the cold cathode tube is transmitted to the thin end by reflection. When the light hits the diffusion point, the reflected light will spread to all angles, and then destroy the reflection conditions and emit from the front of the light guide plate. Diffuse points of different size and density can make the light guide plate emit light evenly. The purpose of the reflecting plate is to reflect the light exposed on the bottom surface back into the light guide plate to improve the use efficiency of light.
