Patent ID: 11927785
Assignee: SINGAPORE UNIVERSITY OF TECHNOLOGY AND DESIGN
Field: Optics (Instruments)
Classification: CPC G  B | IPC B  G

Claim 12:
13. A method of forming a holographic optical element, the method comprising:
forming a hologram portion comprising a plurality of groups of unit regions, each group of unit regions of the hologram portion being configured to produce a respective holographic image under a respective light illumination having a respective predetermined wavelength; and
forming a colour filter portion on the hologram portion, the colour filter portion comprising a plurality of groups of unit regions, each group of unit regions of the colour filter portion being arranged on a corresponding group of the plurality of groups of unit regions of the hologram portion,
wherein said forming the colour filter portion comprises spatially arranging the plurality of groups of unit regions of the colour filter portion to collectively form a predetermined colour image thereon viewable under a white light illumination, and
wherein the light illuminations associated with the plurality of groups of unit regions of the hologram portion, respectively, for producing the respective holographic images are laser illuminations and the respective predetermined wavelengths of the laser illuminations are different from each other.