Optical Information Authentication Research Articles

Optical information authentication using phase-only patterns with single-pixel optical detection.

In this paper, we propose and experimentally demonstrate phase-only authentication based on single-pixel optical imaging through scattering media. The propagating wave is sequentially modulated by using a series of random amplitude-only patterns embedded in a spatial light modulator (SLM), and then a series of one-dimensional (1D) intensity values is recorded by the single-pixel (bucket) detector. Subsequently, an intensity pattern just before the SLM is retrieved by using a correlation algorithm and then further propagates back to the object plane in which the object phase pattern is recovered to serve as reference. Then some single-pixel intensity values are randomly selected from the recorded data, and 1-bit compression is applied to the randomly selected data in order to generate 1D binary signals as ciphertext. A series of random amplitude-only patterns corresponding to the randomly selected single-pixel intensity values serve as principal keys. In a scattering environment, the proposed method is able to carry out phase-only authentication without visually rendering the plaintext, which has not been previously studied. It is found that phase-only authentication is sensitive to security keys, and the proposed method possesses high security. In addition, the proposed method is highly robust to noise contamination and data-loss contamination. Optical experimental results demonstrate the feasibility and effectiveness of the proposed method.

Single-shot in-line holographic authentication using phase and amplitude modulation

In this paper, single-shot in-line holographic authentication using phase and amplitude modulation is presented. Amplitude modulation and phase modulation are presented and conducted at reference wave path to obtain noise-like reference wavefront and to generate the parameters (masks) at reference wave path as security keys for single-shot in-line digital holography, and its application, i.e., optical authentication, is presented to show validity of the proposed digital holographic system. A reference optical path using the cascaded random amplitude-only and phase-only masks is applied as an example. Only one in-line digital hologram is used for object reconstruction, and the recovered objects can be effectively authenticated. It is illustrated that parameters (e.g., masks) flexibly designed at reference wave path can facilitate wavefront retrieval in the CCD plane and also can act like security keys for optical information authentication. @ Elsevier, 2019.

Image authentication using a vector beam with sparse phase information.

We propose a novel optical information authentication scheme that uses Stokes polarimetry of vector beams. Phase-only functions of the plaintext are generated using a modified Gerchberg-Saxton algorithm. Partial information of these phase functions is used to tailor the phase of a vector beam. The Stokes parameters recording of the vector beam generates the ciphertext, which contains sparse information of the input image. In contrast to most authentication schemes, the proposed scheme can authenticate two images from a single real ciphertext. Computer simulation results prove the feasibility of the proposed scheme.

Optical information authentication via compressed sensing and double random phase encoding**This work was supported by the Fundamental Research Funds for the Central Universities (N162410002-4, N151904002), the National Natural Science Foundation of China (No. 61374178).

This paper presents a novel information authentication scheme via compressed sensing and double random phase encoding. Two alternative architectures have been investigated, in which significantly compressed data with micro percentage is sufficient for authentication. At the decoder end, a noise-like image with no leakage of the plaintext is recovered and subsequently authenticated using a nonlinear optical correlation approach. The authentication effectiveness, noise resistance and security performance of the proposed scheme have been experimentally validated.

Shift, rotation and scale invariant optical information authentication with binary digital holography

An optical information authentication system using binary holography is proposed recently, with high security, flexibility and reduced cipher-text size. Despite the success, we point out one limitation of this system that it cannot well verify scaled and rotated versions of correct images and simply regard them as wrong images. In fact, this limitation generally exists in many other optical authentication systems. In this paper, a preprocessing method based Fourier transform and log polar transform is employed to allow the optical authentication systems shift, rotation and scale invariant. Numerical simulation results demonstrate that our proposed scheme significantly outperforms the existing method.

Optical information authentication using compressed double-random-phase-encoded images and quick-response codes.

In this paper, we develop a new optical information authentication system based on compressed double-random-phase-encoded images and quick-response (QR) codes, where the parameters of optical lightwave are used as keys for optical decryption and the QR code is a key for verification. An input image attached with QR code is first optically encoded in a simplified double random phase encoding (DRPE) scheme without using interferometric setup. From the single encoded intensity pattern recorded by a CCD camera, a compressed double-random-phase-encoded image, i.e., the sparse phase distribution used for optical decryption, is generated by using an iterative phase retrieval technique with QR code. We compare this technique to the other two methods proposed in literature, i.e., Fresnel domain information authentication based on the classical DRPE with holographic technique and information authentication based on DRPE and phase retrieval algorithm. Simulation results show that QR codes are effective on improving the security and data sparsity of optical information encryption and authentication system.

Gyrator transform based double random phase encoding with sparse representation for information authentication

Abstract Optical information security systems have drawn long-term concerns. In this paper, an optical information authentication approach using gyrator transform based double random phase encoding with sparse representation is proposed. Different from traditional optical encryption schemes, only sparse version of the ciphertext is preserved, and hence the decrypted result is completely unrecognizable and shows no similarity to the plaintext. However, we demonstrate that the noise-like decipher result can be effectively authenticated by means of optical correlation approach. Simulations prove that the proposed method is feasible and effective, and can provide additional protection for optical security systems.