Secured single-pixel ghost holography

In this paper, we propose and experimentally demonstrate a new optical security method using single-pixel ghost holography. The plaintext is optically encoded into a series of single-pixel data using the designed single-pixel ghost holography, and then a digital hologram just before spatial light modulator (SLM) is retrieved by using a correlation algorithm with all recorded single-pixel data to be stored as a reference in a database. Subsequently, some recorded single-pixel data are randomly selected, and random amplitude-only patterns corresponding to those selected single-pixel data serve as principal security keys. Other parameters, e.g., wavelength and axial distance, can be used as additional security keys. The 1-bit quantization operation is further applied to process those randomly-selected single-pixel data in order to generate binary signals as ciphertext. Finally, different strategies are developed and applied for optical authentication of the decrypted holograms or decrypted objects. Numerical analyses and optical experiments demonstrate that the proposed method possesses high security, high flexibility and high discrimination capability. It is also illustrated that the proposed method possesses high robustness against contaminations. It is believed that the proposed method can provide a promising strategy for greatly enriching optical security field. @ Elsevier, 2020.