Smartbox GridPad 8 Manual page 73

You can customize your Sleep screen settings by going to Settings
– Computer. Here you can turn on automatic dimming, the length
of time before the screen automatically turns off and the dwell
time to wake with eye gaze.
Brightness commands
Use the Set brightness commands in Grid 3 to increase or
decrease the brightness of the screen. If you are looking to
conserve battery, having the brightness set to low can help.
Smartbox recommends the brightness of the screen be set to
70%.
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