Ghost imaging for three-dimensional optical security

Optical authentication via photon-synthesized ghost imaging using optical nonlinear correlation

“…5(a) that due to the use of sparsity strategy, information related to any object cannot be clearly observed. Since the recovered object still contains some invisible but useful information, nonlinear correlation algorithm [24][25][26][27][28][29][30][31][32] is applied to verify the reconstructed object. Fig.…”

“…where N a ðξ; ηÞ and N s ðξ; ηÞ denote nonlinear correlation distributions respectively corresponding to addition and subtraction cases, asterisk denotes complex conjugate, FT and IFT respectively denote 2D Fourier transform and inverse Fourier transform, taðξ; ηÞ denotes the originally added image [taðξ; ηÞ ¼ t 1 ðξ; ηÞþt 2 ðξ; ηÞþt 3 ðξ; ηÞ], tsðξ; ηÞ denotes the originally subtracted image ½tsðξ; ηÞ ¼ t 1 ðξ; ηÞÀt 2 ðξ; ηÞÀt 3 ðξ; ηÞ, and p denotes the strength of applied nonlinearity [24][25][26][27][28][29][30][31][32]. To illustrate the proposed method aforementioned, a flow chart is given in Fig.…”

“…Since sparse reference intensity patterns are applied, the reconstructed objects [i.e.,Ĝ a ðξ; ηÞ andĜ s ðξ; ηÞ] cannot clearly render the visual information. Nonlinear correlation algorithm [24][25][26][27][28][29][30][31][32] is applied to compare the reconstructed objects with the original image (used as reference). The optical authentication methods corresponding to addition and subtraction cases are respectively described by…”

Optical Encryption Scheme with Multiple Users Based on Computational Ghost Imaging and Orthogonal Modulation

“…Recently as a development of GI, the computational ghost imaging (CGI) is successfully applied in the field of optical cryptography [26], which noticeably reduces the number of bits required to transmit and store, because the ciphertext is not a complex-valued matrix but simply an intensity vector. Subsequently, many methods were proposed to improve the security and develop its application [27][28][29][30][31][32]. In addition, several secret sharing schemes were proposed based on combination theory [33][34][35], in which a secret image is encrypted into multiple parts and transmitted separately to multiple users, and the secret can only be decrypted by the qualified set of users.…”

Detecting the Trajectory of Moving Object for Single-Pixel Imaging System

“…In recent years, single-pixel imaging system [6][7][8][9][10][11][12][13] has been paid more and more attention and has been successfully applied in many fields, such as threedimensional imaging [6][7][8][9], optical security [10] and so on [11]. Single-pixel imaging system needs to modulate the illumination light intensity, and the reflected light is detected by single-pixel no-scanning detector.…”