Controllable Optical Vortex Array for Image Encoding

Optical cryptosystems mostly use spatial distributions of amplitude, phase, and polarization of light to encrypt two-dimensional data/image. In this letter, we demonstrate the use of light carrying an array of optical vortices for image encryption. Spatially concatenated orthogonal states of optical vortices allow high-dimensional encoding and minimize the quality degradation during practical implementation. These features offer an efficient way to design an optical cryptosystem.