An inverter and backlight are two important display components. The inverter converts DC power to the higher voltage AC power that is required by the backlight. The backlight shines through the screen and illuminates the display. Two common types of backlights are cold cathode fluorescent lamp (CCFL) and LED. LED monitors use LED-based backlights that do not have fluorescent tubes or inverters.

LCD monitors use CCFL technology for the backlight. The fluorescent tube is connected to an inverter. In most laptops, the inverter, as shown in Figure 1, is behind the screen panel and close to the LCD. The backlight, as shown in Figure 2, is behind the LCD screen. To replace the backlight, you must completely disassemble the display unit.