Shepherd Spectral Imaging of the Atmosphere

1. Auflage 2002
ISBN: 978-0-08-051751-3
Verlag: Elsevier Science & Techn.
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, Band Volume 82, 304 Seiten, Web PDF

Reihe: International Geophysics

Optical instruments are routinely employed to obtain a wealth of information about the atmosphere, including its composition, temperature, and winds. A bewildering variety of optical instruments have been proposed over the years, making it difficult to decide which instrument should be chosen to make a specific measurement. Spectral Imaging of the Atmosphere traces the historical development of both spectral and imaging methods and places them in a unified framework relevant to observations of the troposphere, stratosphere, mesosphere and thermosphere. The underlying concepts of various measurement methodologies are presented and paired with appropriate applications. A selection of specific spectral imaging instruments, appropriate to illustrate each conceptual type, is described in detail.Shepherd's work provides both scientists and engineers with an in-depth understanding of the fundamental concepts they need to know in order to plan a program of atmospheric measurements. Expected future methods and developments are also presented. Problems designed to test and enhance the reader's understanding of the material are included in each chapter.Provides a unique and unifed approach to the methodology of optical atmospheric observations from the troposphere through the thermosphere, which allows the practitioner to choose the best instrument for a given measurement.Describes state-of-the-art atmospheric observing instruments with an eye to future developments.Includes problems designed to test and enhance students' unerstanding of the material presented in each chapter.Contains concise descriptions of selected current and planned spectral imagers, including the Fabry-Perot spectrometer, the Michelson interferometer and the diffraction grating spectrometer.Written from a scientific perspective in an engineering framework, this work is accessible to atmospheric scientists and instrumentation engineers alike.

Autoren/Hrsg.

Shepherd, Gordon G.

Inhaltsverzeichnis

1;Cover;1
2;Copyright Page;5
3;Contents;8
4;Preface;14
5;Chapter 1. Observing Atmospheric Radiation;16
5.1;1.1 Atmospheric Radiation;16
5.2;1.2 Measuring Atmospheric Radiation;23
5.3;1.3 The Scope of Spectral Imaging;27
5.4;1.4 One-Dimensional (Vertical) Spatial Information;28
5.5;1.5 Two-Dimensional (Horizontal–Vertical) Information;31
5.6;1.6 Three-Dimensional Information;33
5.7;1.7 Spectral Information;35
5.8;1.8 Temporal Information;41
5.9;1.9 Preview;43
5.10;1.10 Problems;44
6;Chapter 2. Spectral Concepts;45
6.1;2.1 Introduction;45
6.2;2.2 The Spectral Concept;46
6.3;2.3 Formal Statement of the Fourier Transform;48
6.4;2.4 Fundamental Properties of the Fourier Integral;50
6.5;2.5 Doing a Fourier Integral Without Integration;51
6.6;2.6 Building Up a Set of Fourier Transforms;52
6.7;2.7 Convolutions and Correlations;53
6.8;2.8 The Dirac Delta Function and the Dirac Comb;54
6.9;2.9 The Discrete Fourier Transform;56
6.10;2.10 The Autocorrelation Function and Power Spectral Density;59
6.11;2.11 Optical Devices as Linear Dynamical Systems;60
6.12;2.12 The Diffraction Grating as a Linear Dynamical System;62
6.13;2.13 The Fabry–Perot Etalon as a Linear Dynamical System;66
6.14;2.14 Problems;67
7;Chapter 3. Instrument Responsivity and Superiority;69
7.1;3.1 Responsivity of an Elementary Photometer;69
7.2;3.2 The Measurement of Irradiance;72
7.3;3.3 Responsivity for Line and Continuum Sources;72
7.4;3.4 Photometer Calibration;74
7.5;3.5 Generalized Definition of Responsivity;76
7.6;3.6 Jacquinot’s Definition of Étendue;77
7.7;3.7 Resolving Power and the Superiority of Spectral Imagers;78
7.8;3.8 Dispersion, Classification and Nomenclature;81
7.9;3.9 Problems;83
8;Chapter 4. Imaging Concepts;85
8.1;4.1 Elementary Detectors and Noise;85
8.2;4.2 Scanning Satellite Imager;87
8.3;4.3 Weather Satellite Imagers;91
8.4;4.4 Introduction to Array Detectors;95
8.5;4.5 The Charge Coupled Device (CCD) Detector;96
8.6;4.6 Spectral Response and Materials;102
8.7;4.7 Considerations Specific to Infrared Array Detectors;103
8.8;4.8 Other Types of Array Detectors;104
8.9;4.9 Early Array Detector Imagers;107
8.10;4.10 CCD Satellite Imagers;110
8.11;4.11 Summary;114
8.12;4.12 Problems;115
9;Chapter 5. The Fabry–Perot Spectrometer;117
9.1;5.1 Introduction;117
9.2;5.2 The Idealized Etalon;118
9.3;5.3 The Real Etalon;122
9.4;5.4 Elementary Fabry–Perot Spectrometer Configuration;123
9.5;5.5 The Spherical Fabry–Perot Spectrometer;124
9.6;5.6 Scanning Methods for Fabry–Perot Spectrometers;127
9.7;5.7 The Application of Fabry–Perot Spectrometers;129
9.8;5.8 Applications of the Fabry–Perot Imager;136
9.9;5.9 Problems;142
10;Chapter 6. The Michelson Interferometer;144
10.1;6.1 Historical Background;144
10.2;6.2 Basic Concept;145
10.3;6.3 Spectral Resolution;148
10.4;6.4 Field of View;149
10.5;6.5 The Real Michelson Interferometer;150
10.6;6.6 Sampling the Interferogram;150
10.7;6.7 Superiority of the Michelson Interferometer;151
10.8;6.8 Scanning Methods for the Ordinary Michelson Interferometer;152
10.9;6.9 Some Atmospheric Applications of the Michelson Interferometer;154
10.10;6.10 Field Widening;157
10.11;6.11 Problems;164
11;Chapter 7. Multiplexers and Modulators;166
11.1;7.1 Spectral Operating Modes;166
11.2;7.2 Multiplexers;167
11.3;7.3 Modulators;169
11.4;7.4 Problems;181
12;Chapter 8. Doppler Michelson Interferometry;183
12.1;8.1 The Measurement of Doppler Temperature;183
12.2;8.2 The Measurement of Doppler Wind;187
12.3;8.3 Phase Stepping Interferometry;188
12.4;8.4 The Wide-Angle Michelson Interferometer;190
12.5;8.5 Cube Corner Doppler Michelson Interferometer;191
12.6;8.6 Achromatizing a Field-Widened Michelson Interferometer;192
12.7;8.7 Thermally Stabilizing a Solid Michelson Interferometer;193
12.8;8.8 A Fully Compensated Solid Doppler Michelson Interferometer;194
12.9;8.9 Defocusing a Wide-Angle Michelson Interferometer;195
12.10;8.10 Polarizing Doppler Michelson Interferometers;196
12.11;8.11 The Phase Quadrature Michelson Interferometer;200
12.12;8.12 Optimized Reflective Wide-Angle Phase-Stepping MI;202
12.13;8.13 Problems;204
13;Chapter 9. Operational Atmospheric Spectral Imagers;206
13.1;9.1 Introduction;206
13.2;9.2 The Wind Imaging Interferometer (WINDII);206
13.3;9.3 ERWIN: An E-Region Wind Interferometer;222
13.4;9.4 MICADO – Michelson Interferometer for Coordinated Auroral Doppler Observations;226
13.5;9.5 The High-Resolution Doppler Imager (HRDI);228
13.6;9.6 CLAES: The Cryogenic Limb Array Etalon Spectrometer on UARS;235
13.7;9.7 MOPITT – Measurements Of Pollution In The Troposphere;238
13.8;9.8 Problems;242
14;Chapter 10. Future Atmospheric Spectral Imagers;245
14.1;10.1 The TIMED Doppler Imager (TIDI);245
14.2;10.2 The Mesospheric Imaging Michelson Interferometer (MIMI);250
14.3;10.3 The Stratospheric Wind Interferometer for Transport Studies (SWIFT);255
14.4;10.4 The Atmospheric Chemistry Experiment (ACE);263
14.5;10.5 The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS);266
14.6;10.6 Problems;269
15;Chapter 11. Grating Spectrometers as Spectral Imagers;270
15.1;11.1 Introduction;270
15.2;11.2 Fundamental Aspects of the Diffraction Grating Spectrometer;272
15.3;11.3 Selected Airglow Missions Accomplished;273
15.4;11.4 Selected Atmospheric Missions Accomplished;281
15.5;11.5 Future Atmospheric Missions using Grating Spectrographs;286
15.6;11.6 Spatial Heterodyne Spectroscopy (SHS);289
15.7;11.7 Problems;292
16;Chapter 12. Postscript;294
17;References;296
18;List of Symbols;312
19;List of Acronyms and Abbreviations;315
20;Author Index;320
21;Subject Index;325