Generalized Optics-Free Cross-Correlation Ghost Imaging via Holographic Projection with Grayscale and Binary Amplitude-only Computer-Generated Holograms

TL;DR

This paper introduces an optics-free ghost imaging method using holographic projection with grayscale and binary amplitude-only CGHs, enabling high-quality imaging without traditional optical components, especially useful in challenging wavelength regimes.

Contribution

It presents a novel optics-free ghost imaging scheme utilizing computer-generated holograms and digital micromirror devices, advancing practical applications in difficult-to-fabricate optical regimes.

Findings

Successful replication of light intensity distributions with symmetry

Enhanced imaging quality with sparse target patterns

Potential for high-speed, optics-free imaging in challenging regimes

Abstract

In certain applications or wavelength regimes, essential optical components for imaging systems are either unavailable or challenging to fabricate. To address this, we propose an optics-free classical ghost imaging (GI) scheme utilizing visible light. By employing grayscale and 0-1 binary amplitude-only computer-generated holograms (CGHs), generated via a modified Gerchberg-Saxton algorithm combined with Otsu's thresholding method, we achieve accurate replication of light intensity distributions with central symmetry in the holographic projection plane. Experimentally, we first optimized system parameters by analyzing the point spread function (PSF) and subsequently demonstrated cross-correlation GI through the precise replication of dynamic speckle patterns. Furthermore, by incorporating sparse target patterns, we significantly enhanced the imaging quality. Given the high-speed modulation capabilities of digital micromirror devices (DMDs) for 0-1 binary amplitude-only CGHs, the proposed scheme represents a significant advancement toward practical implementation, particularly in the X-ray regime where conventional optics are difficult to employ.