Yes, the Quick Keys OLED can be Dimmed or adjusted. The Quick Keys out of the box has the OLED brightness set at Bright. There are three states to the brightness of the OLED lights;

  1. Bright
  2. Medium
  3. Dim
  4. Off

I do not suggest that you set the lights to Off as there will not see the names you have given your button commands. 

The instruction below will walk you through changing the Quick Keys OLED brightness. 

Changing the OLED Brightness: 

The first step is to open the Settings Panel. If you have the Pen Tablet and Quick Keys, it will look like the image to the right.

If you only have the Quick Keys, you will see just the Quick Keys listed in the Device Widow.

[1] Shows the Quick Keys in the Device window.

[2] Select the My Quick Keys from the left-hand navigation.

[3] Select Customize, then select [4] Screen brightness, and then you will have a [5] menu of brightness selections.

If you choose Off, no button commands will be displayed on the Quick Keys OLED display.

Changing the Dial light brightness:

You can also adjust the brightness of the lights on the Dial.

[6] Select the Mode.

[7] You can change the Dial light color and [8] the brightness.

This is adjustable for each mode and can also be set to a specific application.

There is no universal off for the Dial light.