Quantum Metrology Imaging and Communication Quantum Optics and Entanglement Two Photon Interference Aberration and Dispersion Cancelation Quantum Metrology Polarization Mode Dispersion Ghost Imaging and Related Topics Quantum Microscopy Correlated and Entangled Orbital Angular Momentum Quantum Communication and Cryptography Appendices A: Review of Optics B: Optical Fields in Quantum Mechanics C: Optical Effects of Aberration and Turbulence D: Phase Matching in Spontaneous Parametric Down Conversion E: Vectorial Scattering Analysis of the Twin Photon Microscope. This book describes the experimental and theoretical bases for the development of specifically quantum mechanical approaches to metrology imaging and communication. In particular it presents novel techniques developed over the last two decades and explicates them both theoretically and by reference to experiments which demonstrate their principles in practice. The particular techniques explored include two photon interferometry two photon optical aberration and dispersion cancellation lithography microscopy and cryptography.