NEC AccuSync LCD72VM User Manual page 59

Brightness
Adjust the background screen brightness by using backlight inverter.
Control range (BAR): 0.0% to 100.0%
Factory setting: 100%
Actual brightness control range: 30% to 100%
30% = (Brightness value [cd/m^2] when user controls Brightness Max) x 0.3
Brightness (Icon select) Brightness (Adjust)
1. During Brightness function operate, Brightness Icon and slide bar color is changed from Normal
condition.
2. "+" Value increase (to bright)
3. "-" Value decrease (to dark)
4. At exiting from this state, adjusted value is saved to EEPROM.
Brightness (Reset)
Recall Brightness value to factory setting
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