Book excerpt: Optical Computing Hardware provides information pertinent to the advances in the development of optical computing hardware. This book discusses the two application areas, namely, high-performance computing and high-throughput photonic switching. Organized into 11 chapters, this book begins with an overview of the requirements on hardware from s system perspective. This text then presents the self-electro-optic-effect devices (SPEED), the vertical-cavity-surface- emitting microlasers (VCSEL), and the vertical-to-surface transmission electrophotonic device (VSTEP). Other chapters consider the fundamental principles of the devices and their operation either as logic devices or for optical interconnection applications. This book discusses as well the planar optical microlens as an example of a refractive microlens of the gradient-index type and explains the diffractive optical elements. The final chapter describes a method for writing and reading optically in parallel from a three-dimensional matrix by means of two-photon interaction in photochromic organic materials. This book is a valuable resource for engineers, scientists, and researchers.