Polycom VVX 500 Owner's Manual page 41

You can modify the Backlight On intensity and the Backlight Idle intensity
separately. You can select high, medium, low and off levels for both.
When you modify the Maximum Intensity, you are modifying the entire
backlight intensity scale. For example, if you decrease the Maximum
Intensity, the low, medium and high values for both Backlight On intensity
and the Backlight Idle intensity decrease.
The Backlight On intensity applies for the following events:
• Any key press
• Hookswitch release
• Incoming call
• Ending a call, holding a call, resuming a call by the other party
• A voice or instant message received
If you do not press any keys on the phone after 20 seconds of the
backlight turning on, the backlight dims (or changes) to medium in the
following cases:
• A call is in progress
• A call is on hold
• There is an incoming call (ringing)
• There is an outgoing call (ringing back)
• Any menu shows on the display
In all other cases, the Backlight Idle intensity applies.
To modify the backlight intensity:
1. Press
2. Tap Settings > Basic > Backlight Intensity.
3. Tap Backlight on Intensity.
4. Tap high, medium or low and then tap save. The default level is
medium.
5. Select Backlight Idle Intensity.
6. Tap high, medium, or low and then press the Select soft key. The
default level is low.
7. Select Maximum Intensity.
8. Tap to Down or Up in the bottom bar to set the intensity level.
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