Laptop LCD display is too dim in darkened room.

Problem:

The laptop display is too dim under low light conditions. When the room light is bright, the display is acceptable.

Affected Models:

Details:

The laptop is equipped with a light sensor that adjusts the LCD brightness based on ambient light conditions. The default configuration of the sensor is not bright enough unless the room light is bright.

Solutions:

  1. Turn off the ambient light sensor: 
    # echo 0 > /sys/devices/platform/asus-laptop/ls_switch

    The screen brightness can now be adjusted via the keyboard brightness keys.

  2. Increase the ambient light sensor ratio: 
    # echo 10 > /sys/devices/platform/asus-laptop/ls_level

    Valid values are 0 - 10.

    The fix can be made permanent by appending the corresponding command to /etc/rc.local.