Definition of Schlieren imaging
Schlieren imaging is a method to visualize density variations in transparent media.
The term "schlieren imaging" is commonly used as a synonym for schlieren photography, though this article particularly treats visualization of the pressure field produced by ultrasonic transducers, generally in water or tissue-mimicking media. The method provides a two-dimensional (2D) projection image of the acoustic beam in real-time ("live video").
The unique properties of the method enable the investigation of specific features of the acoustic field (e.g. focal point in HIFU transducers), detection of acoustic beam-profile irregularities (e.g. due to defects in transducer) and on-line identification of time-dependent phenomena (e.g. in phased array transducers). Some researchers say that schlieren imaging is equivalent to an X-ray radiograph of the acoustic field.
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Frequently asked questions
What is Schlieren imaging?
Schlieren imaging is a method to visualize density variations in transparent media.
Sources & credits
- Wikipedia: Schlieren imaging – CC BY-SA 4.0
- Image by Shmuel Ben-Ezra at English Wikipedia – Public domain