A backlight is a core light-emitting component for LCD displays. Since LCDs do not emit light by themselves, a backlight provides a uniform and stable light source to ensure clear display. A backlight unit usually consists of a light source, light guide plate, diffuser, reflector, and brightness enhancement film. It features uniform brightness, low power consumption, long lifespan, and customizable thickness. By light source, backlights include LED, EL, and CCFL types. By structure, they are divided into edge-lit and direct-lit types. Backlights are widely used in LCD modules, instruments, home appliances, medical devices, automotive displays, industrial control, and other products.