Full text loading...
Geometry of the photoacoustic Doppler flow measurement system.
PAD measurement of the fluid flow in a scattering medium with various speeds. [(a)–(f)] PAD spectra for the average flow speeds from . PSD: power spectral density. (g) PAD shifts calculated from the spectra in (a)–(f). The squared dots plot the mean shifts, the error bars plot the standard deviations of the shifts, and the solid line plots the theoretical mean shifts calculated from Eq. (2) .
PAD signals and spectra measured from the same flow in a scattering medium and in a clear medium. The flow has an average speed of . (a) and signals of the measurement in the scattering medium. (b) and signals of the measurement in the clear medium. (c) PAD spectra obtained from the signals in (a) and (b). PSD: power spectral density.
Negative PAD-shifted ac signals of a flow measured in the scattering medium. The flow has an average speed of . Its direction is reversed from the direction for the data plotted in Fig. 3 and is away from the transducer.
Article metrics loading...