Patent · US Expired

Imaging transverse flow velocity using spectral bandwidth of the doppler frequency shift in phase-resolved optical doppler tomography

US6944551B2 · kind B2 · utility

7Cited by
5References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 12, 2003
Grant dateSep 13, 2005
Priority date
Expiry dateMar 12, 2023

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B5/0073
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

The Doppler bandwidth extracted from the standard deviation of the frequency shift in phase-resolved optical Doppler tomography (ODT) is used to image the velocity component transverse to the probing beam. The effective numerical aperture (NA) of the optical objective determines the slope of the dependence of the standard deviation on velocity. In the case where the angle between the probing beam and flow direction is within ±15 degrees to the perpendicular, the Doppler frequency shift is very sensitive to angle position while the Doppler bandwidth is insensitive to flow direction. Linear dependence of the flow velocity on the Doppler bandwidth allows accurate measurement of flow velocity without precise determination of flow direction. In addition, it also extends the dynamic range of the average frequency shift mapping method used in the phase-resolved ODT.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.