I think similar threads have been posted concerning this but this short video encompasses and briefly explains the technologies of sound and vision for a full rounded 'experience'.
cnn hologram fake alien invasion: together with sound beaming straight into your mind,strontium-barium sulphates as the medium to write the hologram onto (as in chemtrail composition).
http://uk.youtube.com/watch?v=xfQ4nrqZ-2o&feature=email