The classification of volumetric display systems: characteristics and predictability of the image space

A diverse range of volumetric display systems has been proposed during the last 90 years. In order to facilitate a comparison between the various approaches, the three subsystems that comprise displays of this type are identified and are used as a basis for a classification scheme. The general characteristics of a number of volumetric display system configurations are examined, with emphasis given to issues relating to the predictability of the volume within which images are depicted. Key characteristics of this image space are identified and the complex manner in which they depend upon the display unit subsystems are illustrated for several current volumetric display techniques.