Analysis of reconstruction quality for computer-generated holograms using a model free of circular-convolution error

Area of Science:

• Optics and Photonics
• Digital Holography
• Computational Imaging

Background:

• Practical applications often require converting continuous complex-amplitude computer-generated holograms (CGHs) to discrete amplitude-only or phase-only formats compatible with spatial light modulators (SLMs).
• Existing models may not accurately capture the effects of this discretization, leading to wavefront propagation errors during CGH formation and reconstruction.

Purpose of the Study:

• To propose a refined model for emulating wavefront propagation in discretized CGHs, eliminating circular-convolution errors.
• To comprehensively analyze the impact of various discretization parameters on CGH performance.
• To determine optimal quantization strategies for current and future SLM devices.

Main Methods:

• Development of a refined propagation model that avoids circular-convolution errors inherent in discrete Fourier transforms.
• Systematic evaluation of factors including quantization (amplitude/phase), zero-padding, random phase, resolution, reconstruction distance, wavelength, pixel pitch, phase modulation deviation, and pixel-to-pixel interactions.
• Performance analysis based on simulation and experimental validation (implied).

Main Results:

• The proposed model accurately emulates wavefront propagation for discretized CGHs.
• Quantized amplitude and phase, zero-padding rate, random phase, resolution, reconstruction distance, wavelength, pixel pitch, phase modulation deviation, and pixel-to-pixel interaction significantly influence CGH reconstruction fidelity.
• Specific optimal quantization levels and parameter settings are identified for various SLM characteristics.

Conclusions:

• A robust model is presented for accurate simulation of discretized CGH wavefront propagation.
• Understanding the interplay of discretization parameters is crucial for optimizing CGH performance with SLMs.
• The study provides guidance for selecting optimal quantization strategies to maximize the fidelity of holographic reconstructions.