From: Patent Tactics, George Brock-Nannestad


Jos Van Dyck proved that you cannot keep a good idea hidden in these modern 
time. However, it has been successful for some time: the principle was first 
described in a paper given at the AES Convention in Vienna May 2007 (in 
English). You may like to read this patent: US 7,660,208.

The principle is optical like the ELP, however in this case it is not the 
reflected beam whose position is encoded by a linear optical sensor, but the 
illuminating beam, which is colour coded according to the angle it comes 
from. The reflection from the groove seen from a particular direction has a 
colour dependent on the direction it gives to a particular colour according 
to the colour coding scheme and its instant angle of reflection. This colour 
is detected by a videocamera, analysed and converted to a digital signal real-
time. So it is - like the ELP - a velocity-sensitive pickup. I do not yet 
know of any comparisons between the two principles; basically it all comes 
back to the signal-to-noise ratio of the constructions.

Kind regards,



> Researchers at INA in Paris developed a new approach for optical playback 
> of 78 RPM lacquers ("disque souple"). This INA prototype was presented at 
> the AES in Paris by Jean-Hugues Chenot (INA).
> The player is now industrialized by Indeep.