Sunday the 3rd of June 2007 the first free space optics transmission via Blu Ray Laser took place. Wilfried, DJ1WF, sent some TV Signals via 405nm laser to Hannover. The distance between Laser-TX and the ATV repeater DB0TVH was 11,2km. This was the first known free space TV transmission riding the 405nm wave through the atmosphere. The optical output was around 5mW.



Setup with two lasers and 10 GHz receiver to watch the re-transmitted signal from the ATV repeater

red and violet beam to Hannover	405nm Laser to Hannover

The 405nm-colour is violet. Unfortunately the camera changed it to blue.
The red laser was used before the 405nm-transmission to check the detector sensitivity. It was defocused to a wide radiation angle to see if the optical receiver at DB0TVH was still sensitive like in the beginning.