Lytro unveils radical new camera design | Deep Tech - CNET News: Conventional digital cameras uses lenses to focus a subject so it's sharp on the image sensor. That means that for an in-focus part of the image, light from only one direction reaches the sensor.
For light-field photography, though, light from multiple directions hits each patch of the sensor; the camera records this directional information, and after-the-shot computing converts it into something a human eye can understand.
The result that a Lytro camera image is a 3D map of whatever was photographed, and that means people can literally decide what to focus on after they've taken the photo.
"It's got an instant shutter. You press the button--bang! It takes the picture right away," Ng said. "We have that unique feature--shoot first, focus later. The camera doesn't have to physically focus while you take the shot."