CompTIA A+ Core 1 (220-1201)Mobile DevicesMedium
A user reports that their laptop's touchscreen no longer responds to touch, but images and video display normally. Which internal component most likely needs to be replaced?
- ALCD panel
- BBacklight
- CInverter board
- DDigitizer
Show answer & explanationAnswer & explanation
Correct answer: D. Digitizer
The digitizer is the transparent layer that detects touch input and is separate from the LCD panel that renders the image. Since the display works fine but touch input fails, the digitizer is the faulty component.
Why the other options are wrong
- A. The LCD panel controls the visual display, which is working correctly in this case.
- B. A failing backlight would cause a dark or dim screen, not a touch problem.
- C. An inverter board issue would cause dimming/flickering, not loss of touch response.
Digitizer
A transparent touch-sensing layer overlaid on a display that translates finger/stylus contact into input signals.
- Separate component from the LCD/OLED panel
- Failure causes unresponsive touch while display still works
- Often fused with the glass in modern devices
Memory trick: Digitizer 'digs' into your touch, LCD just shows the picture