Physicists discover fundamental property of light can be changed

[Master Oblivious]

Nanophotonics is uncovering the angular momentum of light is not always a multiple of Planck's constant as previously thought. They are going to apply this discovery to furthering the security of optical communications.

http://phys.org/news/2016-05-physicists.html

Where's the "light" coming from when you are asleep and dreaming seeing images of light? Or even just closing your eyes and imagining?