When the laser was invented the occuring patterns - seemingly random bright and dark areas - in the laser spot were considered a disadvantage of this new technolgy. Later scientists began to see the potential of this so-called laser-speckle effect. Since then many various measurement technologies using this phenomenon were discovered. Nowadays this method for measurement is mostly known because of laser-mice. They have a higher precision than LED based optical mice and lack the characteristical glow. Sensors used in these mice are easy to afford and find.

The goal of this work was to use the ADNS-6090 sensor by Avago Technologies to measure rotational speed. For this use hardware and software was designed, which can be easily changed for other laser-speckle based measurements.

Keywords: optical mice, laserspeckles, rotational speed

February 29, 2012