Optical detectors

Abstract

Optical detectors are applied in all fields of human activities from basic research to commercial applications in communication, automotive, medical imaging, homeland security, and other fields. The processes of light interaction with matter described in other chapters of this handbook form the basis for understanding the optical detectors physics and device properties. This chapter starts with a brief historical sketch of first experiments facilitating development of optical detectors. The overview of photo detector types is followed by the description of the most important properties and different detection regimes. A detailed description of different types of optical detectors is presented in the following sections. The device structure and physics as well as important materials for fabrication, figures of merit, and brief application notes are given for photoconductors, photodiodes, quantum well photodetectors, semiconductor detectors with intrinsic amplification, charge transfer detectors, photoemissive detectors, and thermal photodetectors. The chapter includes also a brief overview of imaging systems, principles of black and white and color photography, and recent developments in polymer-, hybrid-, and nanotechnology-based optical detectors.