Fig. 2From: Image encryption using spatial nonlinear opticsMain experimental results. a the plaintext and b its direct image, which serves as the ground truth. The cyphertext images at \(E=0\) Vcm\(^{-1}\) (c), \(-500\) Vcm\(^{-1}\) (e), \(-1000\) Vcm\(^{-1}\) (g) and \(-2000\) Vcm\(^{-1}\) (i), and d, f, h, j the corresponding decrypted image with the correct keys. All the images are normalized and plotted with the colormap hotBack to article page