Sunlight glitter on a wind-ruffled sea: further studies.
Time-averaged intensities are computed for the glitter pattern of sunlight on a wind-ruffled sea. In the present work the azimuthally asymmetric form of the wave-slope distribution measured by Cox and Munk is used, so that the glitter pattern depends on the wind direction as well as magnitude. Results are calculated for both a clean ocean surface and one covered with an oil film. The glitter pattern is quite different with the oil film due to the quieting action of the oil on the waves, the greater reflectivity of the surface when oil is on the surface, and the larger values of polarization for the reflected light at most typical angles in the glitter pattern. These effects are illustrated and discussed as possible methods for the detection of oil slicks. The glitter pattern observed at satellite altitudes is also calculated.
Isophotes of sunlight glitter on a wind-ruffled sea.
Time-averaged intensities are computed for the glitter pattern of sunlight on a wind-ruffled sea. Isopleths are drawn from these on graphs which simulate glitter-pattern photographs through projections of sea-surface grid points on an inclined plane assumed to be in front of the observer. The intensity computed for each grid point is based on a calculation of the wave-surface orientation required for direct reflection from source to observer at that point; the probability of occurrence of this orientation, determined from the Cox-Munk distribution, is the principal factor in the computed intensity. The curvature of the earth is taken into account, and calculations are made for various cases of source elevation angle, observer altitude, and wind speed (the controlling parameter for the distribution of wave inclinations). Percent polarization is computed for the glitter patterns, and projected isopleths of this quantity are plotted. The effects of variations in wind speed, source elevation angle, and observer height on the morphology of the glitter pattern are shown, and such phenomena as the shifting of a reflected image toward the horizon are clearly demonstrated. It is suggested that the technique developed here could be useful in evaluating models of ocean wave structure and in making remote determinations of the sea state in the region of the glitter pattern.
Infrared System Engineering
Part I The Elements of the Infrared System Chapter 1 Introduction to Infrared System Engineering 1.1 The Development of the Infrared Portion of the Spectrum 1.2 The Market for Infrared Devices 1.3 System Engineering 1.4 The System Engineer 1.5 The Infrared System and the Organization of This Book 1.6 The Literature of the Infrared 1.7 The Symbols and Abbreviations Used in This Book Chapter 2 Infrared Radiation 2.1 The Electromagnetic Spectrum 2.2 Terminology Used in the Measurement of Radiant Energy 2.3 The Measurement of Radiant Flux 2.4 Thermal Radiation Thermal Radiation Laws 2.5 Emissivity and Kirchhoff's Law 2.6 Selective Radiators Absorption Spectra of Gases Absorption Spectra of Liquids and Solids Molecular Emission Spectra 2.7 Aids for Radiation Calculations Radiation Slide Rules Charts and Monographs Tables of Blackbody Functions 2.8 Other Blackbody Relationships Efficiency of Radiation Production Radiation Contrast Chapter 3 Sources of Infrared Radiation 3.1 Blackbody-Type Sources Theoretical Principles Construction of a Blackbody-Type Source 3.2 Standards for Sources of Radiant Energy 3.3 General-Purpose Sources of Infrared The Nernst Glower The Globar The Carbon Arc The Tungsten Lamp The Xenon Arc Lamp The Laser The Sun 3.4 Targets The Turbojet Engine The Turbofan Engine The Boeing 707 Jet Transport Afterburning The Ramjet The Rocket Engine Aerodynamic Heating Personnel Surface Vehicles Stars and Planets 3.5 Backgrounds The Earth The Sky Outer Space Stars and Planets Chapter 4 Transmission of Infrared Radiation Through the Earth's Atmosphere 4.1 The Earth's Atmosphere 4.2 Water Vapor 4.3 Carbon Dioxide 4.4 Other Infrared-Absorbing Gases 4.5 Field Measurements of Atmospheric Transmission 4.6 Laboratory and Analytical Methods of Predicting Atmospheric Transmission 4.7 Tables of Atmospheric Transmission Data 4.8 Scattering Effects in the Atmosphere 4.9 Transmission Through Rain 4.10 Atmospheric Scintillation Chapter 5 Optics 5.1 Refraction and Reflection 5.2 Describing an Optical System 5.3 Factors Affecting Image Quality Diffraction Aberrations 5.4 Typical Optical Systems for the Infrared Reflective Optics Refractive Optics Miscellaneous Considerations in the Choice of Optics 5.5 Auxiliary Optics 5.6 Methods of Generating Scan Patterns 5.7 Optical Materials for the Infrared 5.8 Antireflection Coatings 5.9 High-Reflection Coatings 5.10 Optical Filters 5.11 Collimators Chapter 6 Optical Modulation 6.1 Optical Filtering for Background Discrimination 6.2 The Use of Reticles for Background Suppression 6.3 The Use of Reticles to Provide Directional Information Rotating Reticles Stationary Reticles Two-Color Reticles 6.4 Tracking Systems Without Reticles 6.5 Comments on Reticle Design 6.6 Fabrication of Reticles Chapter 7 Introduction to Detectors 7.1 How the Performance of a Detector is Described 7.2 Thermal Detectors The Thermocouple The Thermopile The Bolometer The Pneumatic or Golay Detector The Calorimetric Detector Problems of Blackening Thermal Detectors 7.3 Photon or Quantum Detectors The Photoelectric Detector The Photoconductive Detector The Photovoltaic or p-n Junction Detector The Photoelectromagnetic Detector Spectral Response of Photon Detectors Fabrication of Photon Detectors 7.4 The Comparison of Detectors 7.5 Optically Immersed Detectors 7.6 Imaging Detectors Infrared Film The Image Converter The Vidicon The Photothermionic Image Converter The Evaporograph The Infrared-Sensitive Phosphor Chapter 8 Noise 8.1 Types of Noise Johnson or Thermal Noise Shot Noise Partition Noise 1/f Noise Generation-Recombination Noise Radiation or Photon Noise Temperature Noise Summary - Noise in Detectors 8.2 Equivalent Noise Bandwidth 8.3 The Statistical Description of Noise 8.4 Meters for the Measurement of Noise Peak-Responding Meter Rms-Responding Meter Average-Responding Meter 8.5 Noise Figure Chapter 9 The Measurement of Detector Characteristics 9.1 Quantities To Be Measured 9.2 The Basic Detector Test Set 9.3 Use of the Basic Detector Test Set Measurement of Detector Area Determining the Operating Point of a Detector Determining the Operating Point for a Detector that Requires Bias Determining the Operating Point for a Self-Generating Detector Calibrating the Amplification of the Test Set Measurement of Frequency Response Measurement of the Detector Noise Spectrum Calculation of the Various Figures of Merit 9.4 The Measurement of Spectral Response 9.5 The Measurement of Time Constant 9.6 The Measurement of Detector Response Contours Chapter 10 Modern Detectors and the Ultimate Limits on Their Performance 10.1 Background-Limited Photon Detectors 10.2 Limitations on the Performance of Thermal Detectors 10.3 Considerations in the Selection of a Detector 10.4 Engineering Data on Selected Detectors Chapter 11 Techniques for Cooling Detectors 11.1 Packaging Cooled Detectors 11.2 Low-Temperature Coolants 11.3 Open-Cycle Refrigerators Liquid-Transfer Refrigerators Joule-Thomson Refrigerators Solid-Refrigerant Coolers Radiative-Transfer Coolers Comparison of Typical Open-Cycle Refrigerators 11.4 Closed-Cycle Refrigerators Joule-Thomson (Closed-Cycle) Refrigerators Claude Refrigerators Stirling Refrigerators Refrigerators Using Other Refrigeration Cycles Comparison of Typical Closed-Cycle Refrigerators 11.5 Solid-State Refrigerators Thermoelectric Refrigerators Thermomagnetic Refrigerators 11.6 Integrating the Detector and Refrigerator Chapter 12 Signal Processing and Displays 12.1 General Considerations 12.2 Preamplifiers Preamplifiers Using Vacuum Tubes Preamplifiers Using Transistors Preamplifiers Using Microelectronics 12.3 Additional Considerations in Signal Processing 12.4 Multiple-Channel Systems 12.5 Displays Chapter 13 The Analysis of Infrared Systems 13.1 The Generalized Range Equation Tradeoff Analysis 13.2 The Generalized Range Equation for a Background-Limited Detector 13.3 The Range Equation for Specific Types of Systems Search Systems Tracking Systems that Use Reticles Tracking Systems that Use Pulse Position Modulation 13.4 Line-Scan Thermal Mapping Systems 13.5 Radiometry 13.6 The Specification of System Performance Chapter 14 The Design of an Infrared Search System 14.1 Preliminary Studies 14.2 System Synthesis and Analysis 14.3 Tradeoff Studies and Final System Design Part II The Applications of Infrared Techniques Chapter 15 An Introduction to the Applications of Infrared Techniques 15.1 The Applications of Infrared Techniques 15.2 Miscellaneous References Chapter 16 Military Applications of Infrared Techniques 16.0 General 16.1 Search, Track, and Ranging Applications 16.1.1 Search Systems 16.1.2 Track Systems 16.1.3 Search and Track Systems 16.1.4 Weapon Guidance 16.1.5 Navigation and Flight Control Systems 16.1.6 Ranging Systems 16.2 Radiometric Applications 16.2.1 Measurement of Flux 16.3 Spectroradiometric Applications 16.3.1 Target and Background Signatures 16.3.2 Miscellaneous 16.4 Thermal Imaging Applications 16.4.1 Reconnaissance 16.5 Applications Involving Reflected Flux 16.5.1 Applications of Image Converter Tubes 16.5.2 Infrared Photography 16.6 Applications Involving a Cooperative Source 16.6.1 Terrestrial Communications 16.6.2 Ranging 16.6.3 Infrared Countermeasures 16.6.4 Command Guidance Chapter 17 Industrial Applications of Infrared Techniques 17.1 Search, Track, and Ranging Applications 17.1.1 Search Systems 17.2 Radiometric Applications 17.2.1 Measurement of Temperature 17.2.2 Position Sensing 17.3 Spectroradiometric Applications 17.3.1 Measurement of Temperature 17.3.2 Miscellaneous 17.4 Thermal Imaging Applications 17.4.1 Nondestructive Test and Inspection 17.5 Applications Involving Reflected Flux 17.5.1 Applications of Image Converter Tubes 17.5.2 Infrared Photography 17.5.3 Miscellaneous 17.6 Applications Involving a Cooperative Source 17.6.1 Intrusion Detection 17.6.2 Miscellaneous Chapter 18 Medical Applications of Infrared Techniques 18.1 Search, Track, and Ranging Applications 18.1.1 Obstacle Detection (Passive) 18.2 Radiometric Applications 18.2.1 Measurement of Temperature 18.3 Spectroradiometric Applications 18.3.1 Miscellaneous 18.4 Thermal Imaging Applications 18.4.1 Diagnostic Assistance 18.5 Applications Involving Reflected Flux 18.5.1 Applications of Image Converter Tubes 18.5.2 Infrared Photography 18.5.3 Miscellaneous 18.6 Applications Involving a Cooperative Source 18.6.1 Obstacle Detection (Active) Chapter 19 Scientific Applications of Infrared Techniques 19.1 Search, Track, and Ranging Applications 19.1.1 Search and Track Systems 19.1.2 Navigation and Flight Control Systems 19.2 Radiometric Applications 19.2.1 Measurement of Temperature 19.2.2 Measurement of Flux 19.2.3 World Weather Watch 19.3 Spectroradiometric Applications 19.3.1 Remote Sensing of the Earth and its Atmosphere 19.3.2 Remote Sensing of Astronomical Bodies 19.3.3 Instrumentation and Miscellaneous Applications 19.4 Thermal Imaging Applications 19.4.1 Earth Resource Surveys 19.4.2 Meteorological Applications 19.4.3 Lunar and Planetary Studies 19.4.4 Miscellaneous 19.5 Applications Involving Reflected Flux 19.5.1 Infrared Photography 19.5.2 Reflectance Properties of Materials 19.6 Applications Involving a Cooperative Source 19.6.1 Space Communications 19.6.2 Miscellaneous Appendix 1 The Symbols and Abbreviations Used in This Book a. Simple English Letter Symbols b. Simple Greek Letter Symbols c. Special and Composite Symbols d. Selected Abbreviations Appendix 2 Symbols and Nomenclature for Radiometry and Photometry Appendix 3 Conversion Factors Appendix 4 The Unpublished Literature of the Infrared Index