Spherical self-diffraction for speckle suppression of a spherical phase-only hologram

Area of Science:

• Optics and Photonics
• Holography
• Image Processing

Background:

• Spherical computer-generated holograms (CGHs) often suffer from speckle noise due to the addition of random phase for scattering characteristics.
• Speckle noise significantly degrades the quality of reconstructed images, particularly in spherical phase-only holograms (SPOH).

Purpose of the Study:

• To propose and validate a novel algorithm for speckle noise suppression in SPOH.
• To introduce the Spherical Self-Diffraction (SSD) model and its relation to the Spherical Back-Propagation (SBP) model.

Main Methods:

• Development of the Spherical Self-Diffraction Iteration (SSDI) algorithm.
• Utilizing the Spherical Self-Diffraction (SSD) model, a limiting case of the Spherical Back-Propagation (SBP) model.
• Verification through numerical simulations to confirm the correctness of SBP and SSD models and the effectiveness of the SSDI algorithm.

Main Results:

• The proposed SSDI algorithm demonstrates superior speckle suppression performance compared to conventional methods.
• The SSDI algorithm offers a significant improvement in computing speed.
• Numerical simulations confirmed the effectiveness of the SSDI algorithm and the validity of the SBP and SSD models.

Conclusions:

• The SSDI algorithm is a highly effective method for reducing speckle noise in SPOH.
• The novel SBP and SSD models and the SSDI algorithm represent a significant advancement in holographic image processing.
• This work provides a new approach for enhancing the quality of reconstructed holographic images.