Holography (from Latin, whole+ drawing compound) refers to a technology that allows diffracted light emitted by an object to be reproduced in the same position and size as before. Observing this object from different positions, the image it displays will also change. So the photos taken by this technology are three-dimensional. This technology can be used for optical storage, replication and information processing. Although holography has been widely used to display static three-dimensional images, it is still impossible to display objects arbitrarily by using three-dimensional volume holography.