I'll second it - LaserDisc was an analog medium - not digital. CED was analog also, but used a "stylus" to pick up capacitance changes from the "groove" depth.

I'll second it - LaserDisc was an analog medium - not digital. CED was analog also, but used a "stylus" to pick up capacitance changes from the "groove" depth. There's plenty of information out there on both processes; very interesting to see, you should check it out...