Earlier quoted context omitted.
You can do it with both, actually. Light field data allows you to simulate different viewing angles of the same scene. Depending on the sensor quality you can use this to "see around" objects which occlude the scene from a specific angle (like if you view the image from the center of the field of view). Some limitations, of course, similar to stereoscopic imagery. Using stereoscopic as an example, you can synthesize…
Ah, I see what you mean. You're constrained to viewpoints on the sensor, though, no? So usually a small square.
I think it worked by making a point cloud that fits the camera observations.
Obstruction is not a big issue in that use case, but if there was obstruction, the system could choose to ignore pixels that were obstructed when constructing the image.