Experimental demonstration of ghost-imaging-based authentication in scattering media.

Yin Xiao,Lina Zhou,Wen Chen

doi:10.1364/oe.27.020558

Abstract

Optical imaging in scattering media and its applications are challenging and meaningful. In this paper, we propose and experimentally verify a new optical authentication method using structured-detection-based ghost imaging (GI) in scattering media. Object wave is disturbed by multiple diffusers, and then sequentially modulated by a series of random amplitude-only patterns embedded in a spatial light modulator (SLM). The modulated wave passes through another scattering medium, and its intensity is measured by using a single-pixel bucket detector without spatial resolution. During the decryption and authentication, a reference pattern is first retrieved by using all recorded single-pixel intensity signals. Subsequently, a small number of the recorded single-pixel intensity signals are further randomly selected, and a 1-bit compression operation is applied to these selected intensity signals to generate binary signals as ciphertext. The random amplitude-only patterns corresponding to the selected single-pixel intensity signals serve as principal security keys, and wavelength, axial distance and pixel size can serve as supplementary keys. Two strategies are further developed for the decryption and authentication. It is experimentally verified that the proposed method possesses high robustness and high discrimination capability. The proposed method established by using scattering media can significantly enrich optical security, and provides a promising approach for optical authentication.

Highlights

Optical means becomes a promising and important tool for securing information in recent years
Object wave is disturbed by multiple diffusers, and sequentially modulated by a series of random amplitude-only patterns embedded in a spatial light modulator (SLM)
Since reference pattern needs to be generated for optical authentication, a diffraction intensity pattern just before the SLM is first retrieved by using correlation algorithm with all the recorded single-pixel signals (e.g., 5000) and random amplitude-only patterns embedded in the SLM

Summary

Introduction

Optical means becomes a promising and important tool for securing information in recent years. Since reference pattern needs to be generated for optical authentication, a diffraction intensity pattern just before the SLM is first retrieved by using correlation algorithm with all the recorded single-pixel signals (e.g., 5000) and random amplitude-only patterns embedded in the SLM. Reference pattern needs to be generated for optical authentication, and a diffraction intensity pattern just before the SLM is first retrieved by using correlation algorithm with all the recorded signals and random amplitude-only patterns embedded in the SLM. By using the ciphertext and principal security keys, a diffraction intensity pattern just before the SLM is first retrieved and free-space wave propagation principle is applied to retrieve a decrypted intensity pattern before the SLM (e.g., the object plane) which is correlated with the retrieved intensity pattern [see Fig. 4(a)] to generate a nonlinear correlation map for optical authentication. It is worth noting that the GI-based authentication in scattering media is established over optical encryption and decryption layers without visually rendering object information

Experimental demonstrations and discussion

Findings

Conclusions