Black Instrument Cluster Effect Questions !  

Hey Guys

As some of you will know, a large group of selected vehicles in the Lexus range have an instrument cluster design which enables the entire cluster assembly to be Completely Black when the vehicle is off. You turn the key to the different positions, and depending on the vehicle, different lighting up sequences occur.

Anyway! My question is this:

What causes that effect of total blackness?
(as Lexus clusters are so frekin expensive on Ebay, i cant pull one down and find out for my self..)
Ive got one solution, that is that the perspex covering to the instrument cluster is tinted dark black. When the vehicle is turned on, the lights (LEDS?) in the cluster are Brighter than normal to make up for the black tint = resulting in a (eg. White for some vehicles) White light for the gauges that is easy to read.

For my project car, im creating a new dash-Assembly, and would love this effect. Ill upload pics to my websight, so you guys can see what im upto

Thanks in advance for anyone who can help me