What component illuminates laptop screens?

The component that illuminates laptop screens is the backlight. In LCD (Liquid Crystal Display) screens, the backlight serves as the light source that makes the display visible. The backlight is typically made up of LED (Light Emitting Diode) lights or, in older models, CCFL (Cold Cathode Fluorescent Lamp) technology. It shines through the liquid crystal layers of the display, allowing images and text to be visible to the user.

While the LCD panel itself provides the color and images by manipulating the liquid crystals, it is the backlight that provides the necessary illumination for the screen to be seen. This distinction is essential because it highlights how the different components work together to enable the display's functionality.

The motherboard serves as the main circuit board connecting all components of the laptop, including the display but does not provide illumination. The graphics card is responsible for processing video and rendering images, feeding information to the display, but again, it does not illuminate the screen itself.