Hi Wagner,

Check out this web site:-

http://www.corrsys.de/

Optical vehicle speed measuring device looks straight down, not on
an angle. They even explain the theory of operation.

Brent Brown
Electronic Design Solutions
16 English Street
Hamilton, New Zealand
Ph/fax: +64 7 849 0069
Mobile: 025 334 069
eMail:  brent.brown@clear.net.nz