Display Types (LCD, LED, OLED, Plasma)
Most laptops use either LCD (liquid crystal) or LED (light-emitting diode) displays.
A standard LCD display uses a fluorescent backlight, and is often referred to as an LCD-CCFL (cold cathode fluorescent) display.
Many recent systems use LEDs in place of CCFL components for backlighting. These displays are sometimes referred to as LCD-LED displays.
Organic LED (OLED) displays are common in digital cameras and mobile phones, but have been used in only a few prototype laptops so far.
Plasma displays have not been used in laptops for many years because of their high power con-sumption.
Other Laptop Display Components
A typical LCD-CCFL laptop display includes an inverter (provides power to the backlight), a backlight, and a Wi-Fi antenna. Figure 3-16 shows the location of the inverter, Wi-Fi antennas and wires, and a webcam in a typical laptop display.
If the inverter fails, there is no power to run the backlight. Inverter failure is the most common cause of LCD display failure. However, inverter replacement is relatively inexpensive, and invert-ers can be purchased for do-it-yourself (DIY) replacement.
A CCFL backlight failure is much less common than an inverter failure. If the CCFL backlight fails, a complete disassembly of the display down to individual component level is required, or the display assembly should be replaced.
When servicing the inverter on a typical laptop, follow this general procedure:
1.After removing power from the system (including the battery), follow the procedure to remove the screen assembly.
2.Follow the procedure to remove the display panel from the screen assembly.
3.Disconnect the wires from the inverter.
4.Remove any screws or clips used to secure the inverter.
5.Remove the inverter.
To replace the inverter, reverse this process.
Chapter 3: Laptops 77
Webcam
Microphone
Wi-Fi antennas
Antenna wires and wire guides
Inverter
Figure 3-16 Wi-Fi antennas, wires, CCFL inverter, and webcam in a typical LCD-CCFL display.
Wi-Fi Antenna Components
When servicing the antennas on a typical laptop, follow this general procedure:
1.After removing power from the system (including the battery), turn over the unit and open the cover over the Wi-Fi radio card.
2.Disconnect the wires from the Wi-Fi radio card.
3.Follow the procedure to remove the screen assembly.
4.Follow the procedure to remove the display panel from the screen assembly.
5.Remove the antennas and wires. When reassembling the screen assembly, be sure to replace the wires into the guides located on either side of the display.