Digitising images

How does the exhibit work?

Hold your hand over the black plate. The computer and microcontrollers in this setup will show an image of your hand on the screen

What is the science behind it?

Imagine having to describe every scene in a film, every note of your favourite song, every street around your house, ... as a code of ones and zeros. Impossible? Not really. Because that is exactly what your computer does. It uses ones and zeros, so only two symbols, to remember everything. We call this the binary code.

Look at the plate you are holding your hand over. The circles you see are light sensors. These measure whether light hits them and send signals to the microcontrollers (very simple, little "computers" you see at the bottom of the cabinet).

• On every sensor around your hand, there is light. For the microcontrollers, that is 0.

• On every sensor underneath your hand, there is no light. For the microcontrollers, that is 1.

The microcontrollers are connected to a computer, which ensures that you see those zeros and ones on the screen.

To get more fun images, we also gave the computer other commands:

• 0 = white and 1 = black

• 0 = water and 1 = duckling

Binary code in Braille

If you cannot see (well), you learn to read by feeling the text. The letters are a combination of dots. There are either dots sticking out of the paper, or no dots. Just two symbols. That makes it a binary code. We call this dot alphabet Braille.