Multilayer recording holographic data storage using a varifocal lens generated with a kinoform

Area of Science:

• Optics and Photonics
• Holographic Data Storage
• Information Technology

Background:

• Holographic data storage offers high density.
• Previous methods required mechanical adjustments for multilayer recording.
• Achieving axial multiplexing efficiently is a challenge.

Purpose of the Study:

• To present a new method for multilayer holographic recording.
• To enable axial positioning of holograms without mechanical parts.
• To investigate shift selectivity and multiplexing capabilities.

Main Methods:

• Utilized a kinoform to generate a varifocal lens.
• Introduced a defocus phase to a phase modulation pattern.
• Combined a random phase mask with a computer-generated reference pattern.
• Employed coaxial holographic data storage setup.

Main Results:

• Demonstrated successful multilayer recording along the optical axis.
• Achieved axial displacement of focus positions.
• Experimental results confirmed the feasibility of the proposed method.
• No mechanical movement was required for hologram positioning.

Conclusions:

• The proposed kinoform-based varifocal lens method allows efficient axial multiplexing in holographic data storage.
• This technique eliminates the need for mechanical scanning, simplifying the system.
• It paves the way for advanced, compact holographic storage devices.