Image encryption scheme based on computer generated holography and time-averaged moiré

A technique of computational image encryption and optical decryption based on computer generated holography and time-averaged moir´e is investigated in this paper. Dynamic visual cryptography (a visual cryptography scheme based on time-averaging geometric moir´e), Gerchberg–Saxton algorithm and 3D microstructure manufacturing techniques are used to construct the optical scheme. The secret is embedded into a cover image by using a stochastic moir´e grating and can be visually decoded by a naked eye. The secret is revealed if the amplitude of harmonic oscillations in the Fourier plane corresponds to an accurately preselected value. The process of the production of 3D microstructure is described in details. Computer generated holography is used in the design step and electron beam lithography is exploited for physical 3D patterning. The phase data of a complex 3D microstructure is obtained by Gerchberg-Saxton algorithm and is used to produce a computer generated hologram. Physical implementation of microstructure is performed by using a single layer polymethyl methacrylate as a basis for 3D microstructure. Numerical simulations demonstrate efficient applicability of this technique.

[1]  Xin Sun,et al.  Spread spectrum characteristics of CGH for double random phase encrypted image , 2013 .

[2]  Ernst-Bernhard Kley,et al.  Fabrication and properties of refractive micro-optical beam-shaping elements , 1999, Photonics West - Micro and Nano Fabricated Electromechanical and Optical Components.

[3]  T. Suleski,et al.  Fabrication of high-spatial-frequency gratings through computer-generated near-field holography. , 1999, Optics letters.

[4]  Yurong Wang,et al.  Optical image encryption based on binary Fourier transform computer-generated hologram and pixel scrambling technology , 2007 .

[5]  H P Herzig,et al.  Efficient beam shaping of linear, high-power diode lasers by use of micro-optics. , 2001, Applied optics.

[6]  R. Gerchberg.  A practical algorithm for the determination of phase from image and diffraction plane pictures , 1972 .

[7]  Guofan Jin,et al.  Three-dimensional information hierarchical encryption based on computer-generated holograms , 2016 .

[8]  Frank Wyrowski,et al.  Diffractive Optics for Industrial and Commercial Applications , 1997 .

[9]  Minvydas Ragulskis,et al.  Image communication scheme based on dynamic visual cryptography and computer generated holography , 2015 .

[10]  Moni Naor,et al.  Visual Cryptography , 1994, Encyclopedia of Multimedia.

[11]  G. Spalding,et al.  Computer-generated holographic optical tweezer arrays , 2000, cond-mat/0008414.

[12]  Zenonas Navickas,et al.  Time Average Geometric Moiré—Back to the Basics , 2009 .

[13]  Minvydas Ragulskis,et al.  Image hiding based on time-averaging moiré , 2009 .