Roughly 1 in 10 men are fully or partly colour blind. A smaller percentage of women are color blind. There are various types of color deficits:

Vischeck is a way of showing you what things look like to someone who is color blind. You can try Vischeck online - either run Vischeck on your own image files or run Vischeck on a web page. You can also download programs to let you run it on your own computer.

- Deuteranope (a form of red/green color deficit) -- shown above
- Protanope (another form of red/green color deficit) -- similar effect as shown above
- Tritanope (a blue/yellow deficit- very rare) -- shown in the next slide

http://www.vischeck.com/vischeck/vischeckImage.php