Laser Doppler velocimetry of basilar membrane vibration

Laser Doppler velocimetry of basilar membrane vibration.

A method is described for the measurement of basilar membrane (BM) vibration velocimeter (LDV). The instrumentation was coupled to a compound microscope which served to visualize reflective glass microbeads placed on the BM. The laser beam of the LDV was focused in the microscope object plane and positioned over the reflective bead. We show examples of frequency tuning curves and displacement i...

Laser Doppler Velocimetry

Thermographic laser Doppler velocimetry.

We propose a point measurement technique for simultaneous gas temperature and velocity measurement based on thermographic phosphor particles dispersed in the fluid. The flow velocity is determined from the frequency of light scattered by BaMgAl10O17:Eu2+ phosphor particles traversing the fringes like in conventional laser Doppler velocimetry. Flow temperatures are derived using a two-color rati...

Laser Doppler Vibrometry measurements of human cadaveric tympanic membrane vibration

OBJECTIVE To determine the feasibility of measuring tympanic membrane (TM) vibrations at multiple locations on the TM to differentiate normal eardrums from those with associated ossicular pathologies. DESIGN Cadaveric human temporal bone study. SETTING Basic science laboratory. METHODS A mastoidectomy and facial recess approach was performed on four cadaveric temporal bones to obtain acce...

Diffractive beam splitter for laser Doppler velocimetry.

A miniaturized sensor head for the optical measurement of velocities of fluids based on laser Doppler velocimetry is demonstrated. Holographic optical elements mounted on a glass substrate are used for beam splitting and deflection. Volume holograms in dichromated gelatin exhibit good optical efficiency (75% transmission of a cascade of two holographic optical elements). With diffractive device...