Through the phone menus you can change the contrast used on the display.
This option is shown on J169 phones only. If the phone also has button module's attached, you can separately adjust the contrast of each modules display.
Procedure
Press the button.
Use the cursor keys to select Settings.
Use the cursor keys to select Display.
Use the cursor keys to select Contrast.
Use the left/right cursor keys to adjust the contrast as required.