When I first entered the internet in 2000, the first G-Shock I found was a DW-9005V. It looked black on the picture, but it was actually dark blue when I bought it a short while later. The coolest feature on this watch was the reversed display. A black background with white digits.

In the meanwhile I now have several G-Shocks with a reversed display, but how does it work...

The LCD's of a G-Shock contain a liquid that can act as a solid. The compounds having this ability are called Liquid Crystals. The most used liquid crystals are cholesterol derivates. One of most important  abilities of a liquid crystal is that it is able to turn polarized light when put on an electric potential. The twist of the light depends on the voltage.

On a day I discovered a student, making his homework with a Casio calculator with a reversed display. He told me that it was really quit simple. You only had to open up your calculator and turn around the protection of the LCD screen.

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