The classic PC screen on our desk can only display 2D image content, which looks identical from every viewing direction. A light field display, on the other hand, can simultaneously project different information in different directions. Imagine a display in the center console of the car that shows the driver the navigation while the front passenger can watch a movie at the same time. We go even further and project different image content in up to 1,600 different directions at the same time.
A light field emitter is a planar light source in which both the position and the direction of light emission can be controlled. Our prototype combines a monitor with an array of lenses mounted in front of it at the distance of the focal lengths of the individual lenses. If a pixel is activated behind an individual lens, the light field display emits a parallel bundle of rays whose direction of propagation is defined by the spatial position of the activated pixel behind the individual lens. In this way a 4D light field is projected into space. Its spatial resolution corresponds to the number of individual lenses in the lens array; the angular resolution is determined by the number of monitor pixels behind each individual lens.