From Focal Stack to Tensor Light-Field Display

We propose a method of using a focal stack, i.e., a set of differently focused images, as the input for a novel light field display called a “tensor display.” Although this display consists of only a few light attenuating layers located in front of a backlight, it can be viewed from many directions (angles) simultaneously without the resolution of each viewing direction being sacrificed. Conventionally, a transmittance pattern is calculated for each layer from a light field, namely, a set of dense multi-view images (typically dozens) that are to be observed from different directions. However, preparing such a massive amount of images is often cumbersome for real objects. We developed a method that does not require a complete light field as the input; instead, a focal stack composed of only a few differently focused images is directly transformed into layer patterns. Our method greatly reduces the cost of acquiring data while also maintaining the quality of the output light field. We validated the method with experiments using synthetic light field data sets and a focal stack acquired by an ordinary camera.