A method for preparing a colorful three-dimensional hologram based on holographic polymer dispersed liquid crystal gratings comprises: first, in a 441.6 nm laser interference field, preparing with holography a holographic master (7) which stores the reflected (or transmitted) light wave information (amplitude and phase) of an object captured; then using an object light (6) to irradiate the holographic master at a Bragg angle to generate a diffraction light (8); and using the diffraction light and a reference light (10) to simultaneously irradiate a holographic base board (9) comprising a photosensitizer, a co-initiator, a monomer capable of free radical polymerization , and a liquid crystal so that, when total optical paths of the two laser beams reaching the holographic base board are equivalent to each other, optical coherence occurs between the two laser beams on the holographic base board, thereby obtaining a colorful three-dimensional hologram based on holographic polymer dispersed liquid crystal gratings from which an image of the captured object can be observed in the sunlight.
METHOD FOR PREPARING COLORFUL THREE-DIMENSIONAL HOLOGRAM BASED ON HOLOGRAPHIC POLYMER DISPERSED LIQUID CRYSTAL GRATING