If you can't read the display in normal ambient light (and assuming you have normal eyesight) then there is no doubt that the display is faulty. In the office under flourescent lighting plus ambient daylight I can easily see a blue display across the office, approx 10 metres. You should be able to turn the dimmer all the way down and still be able to see the display easily at night and quite clearly under ambient daylight.
If this is not the case contact
[email protected] and get it fixed before your warranty expires. If you follow Hugo's instructions then make sure you know what you're doing because you won't have a warranty when you've finished.
Rob