Shoot First, Focus Later

To get the effect, click on parts of the images in the foreground and background. 

Very intriguing. (thx KS)

From Lytro...

[The light field] is the amount of light traveling in every direction through every point in space. Conventional cameras cannot record the light field.

The light field sensor captures the color, intensity and vector direction of the rays of light. This directional information is completely lost with traditional camera sensors, which simply add up all the light rays and record them as a single amount of light.

[Light field cameras] allow both the picture taker and the viewer to focus pictures after they're snapped, shift their perspective of the scene, and even switch seamlessly between 2D and 3D views.