The Special Issue "Liquid Crystal Optical Devices" discusses recent developments in the rapidly advancing subject of liquid crystals (LCs). The book is composed of several contributions from researchers in the field of liquid crystals that deal with the broadly with aspects of optical devices ranging from a theoretical viewpoints to practical implications of the properties of LCs. This is the first Special Issue devoted solely to recent advances in the rapidly expanding subject of LCs, a unique class of substances that combines both ordered structures with quasi-liquid-like properties. This Special Issue offers a broad perspective of the present state of the art in design and an up-to-date account of the most recent advances and progress in the field of LCs, providing thorough coverage of the demonstrated optical devices and the comprehensive analysis needed by professionals and engineers in the field of LC. The material is carefully structured, providing readers with a solid foundation of the principles, capabilities, use, and limitations of LC optical devices. In addition, this book covers the principles, recent advances and future developments of liquid crystal beam steering devices as well as recent advances in adaptive liquid crystal lenses.