This book will serve as a comprehensive technical guide, covering fundamentals, recent advances and issues in the field of optics. The chapters in this book have been written by highly professional authors. This book contains valuable information, which will assist a wide range of readers in practical applications. It also talks about the optical tools, which are used to study light, characteristics of light and different types of fibres. The objective of the book is to serve as a valuable reference for students, educators, scientists, faculty members, researchers, engineers and research strategists in the rapidly evolving field of optics.