Holography is divided into two processes which are recording and reproduction, the interference fringes is generated on the holographic plate through the superposition between the reference light and the reflected light during the recording. Then, after the holographic plate is processed in the darkroom, an image exactly same to the original object will be reproduced from the interference pattern on the photosensitive sheet by diffraction. Compared with ordinary photographic, Holography not only records the amplitude of light field of the object, but also records the relative phase of the reflected light waves. Holography is widely used in holographic microscopy, holographic security, data storage, deformation measurement, holographic interferometry and etc.

Three-dimensional color holograms can reflect the original information of objects more accurately than monochromatic holograms, so they have a broad application prospect in holographic display. In order to realize high-definition, large-format and THREE-DIMENSIONAL color holographic display, holographic Angle multiplexing, holographic rotation multiplexing and holographic wavelength multiplexing are used to realize multi-multiplexing holographic display in liquid crystal thin film, and RGB tri-color laser is used to realize the reproduction of RGB image components. The RGB image components are recorded in three different holograms, which are recorded at the same recording point of the liquid crystal film using angular multiplexing. The green laser is used as a recording light to record three holograms at the same time, and then the red, green and blue laser reads the corresponding holograms respectively. These three RGB images are combined into three-dimensional color holograms.

At present, three-dimensional color holographic technology in three-dimensional film, television, exhibition, microscopy, interferometry, projection lithography and surveillance, underwater detection, metal interior detection, preservation of precious historical relics, works of art, information storage, remote sensing, The study and recording of transient phenomena, transient processes (such as explosions and combustion) with extremely rapid changes in physical states have been widely used.