Bushwalk Australia

http://www.lytro.com/

Go to the gallery, find a photo, click on the point that you want focussed, and then try & understand... HOW???

http://player.sbs.com.au/naca#/naca/wna ... xes-focus/

Closing quote –
“And because the camera captures so much light, you can also take your own 3D photos.”

Yeah, their "science" section doesn't really enlighten. If it was my invention, I might keep quiet about that too. There must be more than one sensor...they are recording distance information.
Life's hard enough with 2D photos.....