The lytro company is currently developing a light field camera is completely different to current camera architecture. you can capture a “picture” and set the focus later. here are some features of this type of cam taken from their faq page
Shoot now, focus later: Because the camera captures the entire light field, there is no need to focus ahead of time. You can simply capture the moment, and adjust the focus later. This means you can concentrate on what’s happening in the scene, not fiddle with your camera. Lytro pictures can be focused to your liking days, weeks, even years after they’re taken.
Unparalleled speed: This is fast. Since the camera doesn’t focus before a photo is taken, you don’t miss important moments due to autofocus shutter lag.
Living pictures. When shared online, both the photographer and viewer can play with Lytro pictures, including changing the focus.
Low-light sensitivity: Everyone knows low light pictures are usually very entertaining, but they’re also pretty difficult to capture with a regular camera or cell phone. By using all of the available light in a scene, Lytro cameras capture great pictures in low light environments without use of a flash – from clubs to concerts to candlelit dinners.
Immersive 3D: Using the full light field, Lytro cameras will allow you to easily switch between 2D and 3D views or shift the perspective of the scene.
Here are some results to play with. just click the picture to set the focus to that specific point (and depth)
More demo pictures can be found here.