Glossary of Symbols and Acronyms

Introduction to Radiometry

The Electromagnetic Spectrum

The Basics

Propagation of Optical Radiation

Plane and Solid Angles

Projected Area and Projected Solid Angle

f/# and Numerical Aperture

Radiometric Quantities Summarized

Photon Quantities

Spectral Radiant Quantities

Radiance, Radiant Exitance, and Intensity

Exitance-Radiance Relationship

Intensity

Isotropic and Lambertian Sources

Inverse Square Law of Irradiance

Cos3 and Cos4 Laws of Irradiance

Throughput and its Invariance

Area and Solid Angle Products

Basic Radiance and Radiance Invariance

The Equation of Radiative Transfer

Configuration Factors

Power Transfer: Point Source

Power Transfer: Extended Source

Power Transfer: Field Lens Added

Irradiance from a Lambertian Disk

Irradiance from a Lambertian Sphere

The Integrating Sphere

Camera Equation and Image Plane Irradiance

Radiometric Properties of Materials

Overview of Material Properties

Transmission

Reflection

Absorption and the Conservation of Energy

Emission

Specular Transmissivity and Reflectivity

Single-Surface Illustrations

More on Specular Propagation

Transmission: Absorbing and Reflecting Materials

Materials as Targets

Optical Materials Selection Considerations

Generation of Optical Radiation

Planck's Law

Stefan-Boltzmann and Wien Displacement Laws

Rayleigh-Jeans and Wien Approximations

Radiation Laws in Terms of Photons

Kirchoff's Law

Natural Sources

Lambert-Bouguer-Beer Law and Langley Plot

Artificial Sources

Luminescent Mechanisms

Some Luminescent Sources

Detectors of Optical Radiation

Detector Types

Detector Definitions

More Detector Definitions

Detector Figures of Merit

Noise Concepts and Definitions

The Most Unpleasant Noises

More Unpleasant Noises

Thermal Detectors

Thermoelectric Detectors

The Bolometer

Pyroelectric Detectors

Photon Detectors

Photoconductive Detectors

Photoemissive Detectors

Photovoltaic Detectors

Photovoltaic Current and Performance

Detector Interfacing

Single and Multiple Detectors

Detector Array Architectures

Choosing a Detector

Radiometric System Components

Choppers and Radiation References

Baffles and Cosine Correctors

Spectral Separation Mechanisms

Prisms and Gratings

Filters

Calibration and Measurement

Radiometric Calibration Basics

Radiometric Calibration Philosophy

Distant Point Source Calibration

Collimators and the Distant Small Source

More on Collimators

Extended Source Calibrations

Other Calibration Methods

The Measurement Equation

Errors in Measurements

Signal-to-Noise Ratio and Measurement Error

The Range Equation

Radiometric Temperatures

Photometry

Photometric Quantities

Human Visual Response

Color

Sources and the Eye's Response

Appendices

SI Base Quantities, Prefixes, and Uncertainty Reporting

Physical Constants: 2010 CODATA Recommended Values

Source Luminance Values

More Source Values

Solid Angle Relationships

Rays, Stops, and Pupils

Diffraction

Action Spectra and Optical Radiation Regions

Equation Summary

References

Bibliography

Index

Preface

Based on the SPIE bestseller The Art of Radiometry by James M. Palmer and Barbara G. Grant, this Field Guide provides a practical, hands-on approach to the subject that the engineer, scientist, or student can use in real time. Readers of the earlier work will recognize similar topics in condensed form, along with many new figures and a chapter on photometry.

Written from a systems engineering perspective, this book covers topics in optical radiation propagation, material properties, sources, detectors, system components, measurement, calibration, and photometry. Appendices provide material on SI units, conversion factors, source luminance data, and many other subjects. The book's organization and extensive collection of diagrams, tables and graphs will enable the reader to efficiently identify and apply relevant information to radiometric problems arising amid the demands of today's fast-paced technical environment.

I gratefully acknowledge the contributions to my education and career from three professors of Optical Sciences at the University of Arizona, gentlemen all. They are the late Jim Palmer (1937-2007), who mentored me in radiometry for many years and provided the opportunity for me to complete The Art of Radiometry; Emeritus Professor Phil Slater, who selected me as a graduate student and trained me in remote sensing, and who continues to encourage and support me; and Eustace Dereniak, who generously shared his knowledge from the very first, provided me my first opportunities to teach, and has strongly supported my career for more than twenty years. To all, my heartfelt thanks.

This book is dedicated to my family and particularly to the memory of my father, William Grant of Chicago, Illinois, a US Navy veteran of WWII who taught me to play the "Garryowen" as soon as my fingers could reach a piano keyboard.

Barbara G. Grant
October 2011