Accurate reconstruction of horizontal parallax-only holograms by angular spectrum and efficient zero-padding

Area of Science:

• Optics and Photonics
• Digital Holography
• Computational Imaging

Background:

• Accurate reconstruction of horizontal parallax only digital holograms (HPO-DHs) typically requires non-paraxial propagation methods like the angular spectrum (AS) method.
• The high space-bandwidth product (SBP) of HPO-DHs leads to computationally intensive reconstructions and challenges with aliasing removal using zero-padding.

Purpose of the Study:

• To develop a novel angular spectrum technique for reconstructing non-paraxial HPO-DHs with a significantly reduced space-bandwidth product (SBP).
• To overcome the computational burden associated with large SBP requirements and zero-padding in HPO-DH reconstruction.

Main Methods:

• Proposed a new AS technique utilizing multi-Fourier transform plane propagation to avoid vertical size increase.
• Employed coherent superposition of vertical tiles derived from multi-Fourier transform calculations.
• Implemented efficient SBP management enabling zero-padding strategies in the x-direction across frequency, space, and space-frequency domains.

Main Results:

• The developed methodology enables the reconstruction of HPO-DHs using the AS method with a substantially reduced SBP.
• Efficient SBP management allows for effective zero-padding strategies, leading to simultaneous suppression of aliased components and enhancement of spatial resolution.
• Numerical simulations and experimental results validate the accuracy and utility of the proposed technique.

Conclusions:

• The novel AS technique effectively reconstructs non-paraxial HPO-DHs with reduced SBP, addressing computational limitations.
• The method allows for simultaneous aliasing suppression and spatial resolution enhancement, proving its practical applicability.
• This approach offers a computationally efficient and accurate solution for HPO-DH reconstruction.