1 Historical Background -- 1.1 The 17th Century -- 1.2 The 18th Century -- 1.3 The 19th Century -- 1.4 The 20th Century -- 2 Basic Concepts -- 2.1 Light Propagation Through Inhomogeneous Media -- 2.2 Definition of a Schliere -- 2.3 Distinction Between Schlieren and Shadowgraph Methods -- 2.4 Direct Shadowgraphy -- 2.5 Simple Lens-Type Schlieren System -- 2.6 On the Aspect of a Schlieren Image -- 3 Toepler's Schlieren Technique -- 3.1 Lens- and Mirror-Type Systems -- 3.2 Sensitivity -- 3.3 Measuring Range -- 3.4 Estimating the Sensitivity and Range Required -- 3.5 Resolving Power -- 3.6 Diffraction Effects -- 3.7 Magnification and Depth of Field -- 4 Large-Field and Focusing Schlieren Methods -- 4.1 Large Single- and Double-Mirror Systems -- 4.2 Traditional Schlieren Systems with Large Light Sources -- 4.3 Lens-and-Grid Techniques -- 4.4 Large-Field Scanning Schlieren Systems -- 4.5 Moiré-Fringe Methods -- 4.6 Holographic and Tomographic Schlieren -- 5 Specialized Schlieren Techniques -- 5.1 Special Schlieren CutoffsIll -- 5.1.1 Graded Filters -- 5.2 Color Schlieren Methods -- 5.3 Stereoscopic Schlieren -- 5.4 Schlieren Interferometry -- 5.5 Computer-Simulated Schlieren -- 5.6 Various Specialized Techniques -- 6 Shadowgraph Techniques -- 6.1 Background -- 6.2 Direct Shadowgraphy -- 6.3 "Focused" Shadowgraphy -- 6.4 Specialized Shadowgraph Techniques -- 7 Practical Issues -- 7.1 Optical Components -- 7.2 Equipment Fabrication, Alignment, and Operation -- 7.3 Capturing Schlieren Images and Shadowgrams -- 7.4 Commercial and Portable Schlieren Instruments -- 8 Setting Up Your Own Simple Schlieren and Shadowgraph System -- 8.1 Designing the Schlieren System -- 8.2 Determining the Cost -- 8.3 Choosing a Setup Location -- 8.4 Aligning the Optics -- 8.5 Troubleshooting -- 8.6 Recording the Schlieren Image or Shadowgram -- 8.7 Conclusion -- 9 Applications -- 9.1 Phenomena in Solids -- 9.2 Phenomena in Liquids -- 9.3 Phenomena in Gases -- 9.4 Other Applications -- 10 Quantitative Evaluation -- 10.1 Quantitative Schlieren Evaluation by Photometry -- 10.2 Grid-Cutoff Methods -- 10.3 Quantitative Image Velocimetry -- 10.4 Quantitative Shadowgraphy -- 11 Summary and Outlook -- 11.1 Summary -- 11.2 Outlook: Issues for the Future -- 11.3 Closing Remarks -- References -- Appendix A Optical Fundamentals -- A. 1 Radiometry and Photometry -- A.2 Refraction Angle 8 -- A.2.1 Small Optical Angles and Paraxial Space -- A.2.2 Huygens' Principle and Refraction -- A.3 Optical Components and Devices -- A.3.1 Conjugate Optical Planes -- A.3.2 Lensf/number -- A.3.3 The Thin-Lens Approximation -- A.3.4 Viewing Screens and Ground Glass -- A.3.5 Optical Density -- A.4 Optical Aberrations -- A.5 Light and the Human Eye -- A.6 Geometric Theory of Light Refraction by a Schliere -- Appendix B The Schlieren System as a Fourier Optical Processor -- B. 1 The Basic Fourier Processor with no Schlieren Present -- B.2 The Addition of a Schlieren Test Object -- B.3 The Schlieren Cutoff -- B.4 Other Spatial Filters -- B.5 Partially-Coherent and Polychromatic Illumination -- Appendix C Parts List for a Simple Schlieren/ Shadowgraph System -- C.l Optics -- C.2 Illumination -- C.3 Miscellaneous Components -- C.4 Optical Mounts -- Appendix D Suppliers of Schlieren Systems and Components -- D.l Complete Schlieren Systems -- D.2 Schlieren Field Mirrors -- D.3 Light Sources -- D.4 Components -- D.5 Focusing Schlieren Lenses -- D.6 Miscellaneous -- Color Plates.