Cameras, both old-school and digital, record light to produce an image. One thing they don't do, however, is record where the light is coming from, until now...
A new camera by a company called Lytro records not only the light of a scene, but also where the light is coming from, bouncing off of people's faces, flower petals, windows, etc. This is called capturing the light field.
Here is an explanation from the Lytro web site about how it works:
Recording light fields requires an innovative, entirely new kind of sensor called a light field sensor. 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.By recording the direction of the light coming into the camera, the Lytro software allows photographers to change the focus within a photograph after a picture has been taken. In the picture above, you can click on the squares to focus on the window, or click on the colorful blobs to focus on the people on the street.
It's a neat effect that may or may not have commercial appeal to photographers on the street but may be very useful for security cameras, where something happening in the foreground or background that would otherwise be out of focus could be made clear. The camera will also allow photographers to take a new kind of 3D image.
The camera isn't available for purchase yet, but the Lytro web site says it will be debuted sometime this year. To see more cool images by this new type of camera, check out their gallery.