Holographic optical element printing method using tunable focus lens and rotating mirror

Abstract

Provided is a holographic optical element printing method using a tunable focus lens and a rotating mirror. According to an embodiment, a holographic printer includes: a first optical engine and a second optical engine configured to adjust a phase of an incident collimated beam and emit the collimated beam; and a first reduction optical system and a second reduction optical system configured to reduce the beam emitted from the first optical engine and the second optical engine and to allow the beam to enter a holographic material, wherein each of the first optical engine and the second optical engine includes: a rotating mirror configured to reflect while adjusting the phase of the incident collimated beam through rotation; and a tunable focus lens configured to refract while adjusting the phase of the incident collimated beam reflected from the rotating mirror through focus tuning. Accordingly, by using a combination of a tunable focus lens and a rotating mirror, instead of using an SLM of a holographic printer, quality of an HOE may be enhanced, a printing time per hogel may be reduced and a total recording time may be greatly reduced when holographic printing of the HOE is performed.