Digital holography for recognition and security of 3D objects

Abstract

Three-dimensional (3D) object recognition has been achieved by comparing either holograms or the reconstructed images from respective holograms using conventional and nonlinear joint fractional transform correlators. For 3D information security, an encrypted image has been used as digital watermark. The encryption scheme is based on polarized light encoding and the photon counting technique. Multiple images may also be used as watermark. A multiple image encryption system has been proposed which is based on phase mask multiplexing and photon counting imaging.