Optical Cryptosystems. Naveen K. Nishchal
Shenzhen University with whom I have had the opportunity to interact and learn the subject.
I must thank Elsevier, OSA, and SPIE for allowing me to reuse some of their diagrams/images published in various journals. Thanks are due to Jessica Fricchione, Poppy Emerson, and Sarah Armstrong from IOP Publishing, UK, for guiding me on many issues while preparing the manuscript.
I wish to extend my sincere thanks to all my students, Dr Sudheesh K Rajput, Dr Isha Mehra, Dr Dhirendra Kumar, Dr Areeba Fatima, Alok K Gupta, Avishek Kumar, Praveen Kumar, and Yatish. My continuous interactions with them have led me to a deeper understanding of the subject. They helped me in preparing this manuscript and drawing some of the difficult diagrams.
Finally, I owe a lot to my family—particularly to my wife Rinki and my son Anvit for allowing me to spend long hours in preparing this manuscript and for their support throughout. I also thank my other family members in appreciation of their patience, encouragement, and constant support while this manuscript was being prepared.
Author biography
Naveen Kumar Nishchal
Dr Naveen Kumar Nishchal is an associate professor in the Department of Physics at the Indian Institute of Technology (IIT) Patna. He joined IIT Patna in December 2008. Dr Nishchal received his PhD degree in physics from IIT Delhi in 2005. He joined Instruments Research and Development Establishment, Dehradun, under Defence Research and Development Organisation, as a Scientist ‘C’ in July 2004 and worked until June 2007. Subsequently, he moved to IIT Guwahati and worked as an assistant professor in the Department of Physics from June 2007 to November 2008. He has been a visiting researcher to the Oulu Southern Institute, University of Oulu, Finland. His research interests include optical information processing, image encryption, watermarking, digital holography, interferometry, correlation-based optical pattern recognition, and fractional Fourier transform-based signal processing. Dr Nishchal is a senior member of OSA, SPIE, and life member of the Optical Society of India. He is a life member of Indian Science Congress Association, and Lasers and Spectroscopy Society of India. He has authored or co-authored 60 peer-reviewed international journal papers, two book chapters, and 150 papers in various conferences/seminars/symposia.
List of acronyms
| AES | Advanced encryption standard |
| AT | Amplitude-truncated |
| BE | Beam expander |
| BR | Bacteriorhodopsin film |
| BS | Beam splitter |
| CC | Cross-correlation |
| CCA | Chosen-ciphertext attack |
| CCD | Charge-coupled device camera |
| CGH | Computer generated hologram |
| CMOS | Complementary metal-oxide semiconductor |
| COA | Ciphertext-only attack |
| CPA | Chosen-plaintext attack |
| CS | Compressive sensing |
| CT | Computed tomography |
| 1D | One-dimensional |
| 2D | Two-dimensional |
| 3D | Three-dimensional |
| DCT | Discrete cosine transform |
| DES | Data encryption standard |
| DH | Digital holography |
| DOE | Diffractive optical element |
| DRPE | Double random phase encoding |
| DWT | Discrete wavelet transform |
| EFJPS | Encrypted fractional joint power spectrum |
| EMD | Equal modulus decomposition |
| ERA | Error reduction algorithm |
| FT | Fourier transform |
| FFT | Fast Fourier transform |
| FRT | Fractional Fourier transform |
| FrT | Fresnel transform |
| FWT | Fractional wavelet transform |
| GSA | Gerchberg–Saxton algorithm |
| GT | Gyrator transform |
| GWT | Gyrator wavelet transform |
| HIOA | Hybrid input–output algorithm |
| HM | Holographic mask |
| HOE | Holographic optical element |
| HT | Hartley transform |
| HWP | Half wave plate |
| IDEA | International data encryption algorithm |
| IFT | Inverse Fourier transform |
| JPS | Joint power spectrum |
| JTC | Joint transform correlator |
| KPA | Known-plaintext attack |
| LC | Liquid crystal |
| LCT | Linear canonical transform |
| LCTV | Liquid crystal television |
| LED | Light-emitting diode |
| MATLAB | Matrix laboratory |
| MEMS | Micro-electro-mechanical systems |
| MO | Microscope objective |
| MGSA | Modified Gerchberg–Saxton algorithm |
| MRI | Magnetic resonance imaging |
| MSE | Mean square error |
| MZI | Mach–Zehnder interferometer |
| NIST |
National Institute of Standards |