Ultrasound-modulated optical imaging using a powerful long pulse laser.
Ultrasound-modulated optical imaging (or tomography) is an emerging biodiagnostic technique which provides the optical spectroscopic signature and the localization of an absorbing object embedded in a strongly scattering medium. We propose to improve the sensitivity of the technique by using a pulsed single-frequency laser to raise the optical peak power applied to the scattering medium and thereby collect more ultrasonically tagged photons. Moreover, when the detection of tagged photons is done with a photorefractive interferometer, the high optical peak power reduces the response time of the photorefractive crystal below the speckle field decorrelation time. Results obtained with a GaAs photorefractive interferometer are presented for 30- and 60-mm thick scattering media.
Rousseau
Guy
G
Industrial Materials Institute, National Research Council of Canada, Boucherville, Québec, Canada. guy.rousseau@cnrc-nrc.gc.ca
Blouin
Alain
A
Monchalin
Jean-Pierre
JP
D054459:Elasticity Imaging Techniques / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007368:Interferometry / Q000295:instrumentation*; D007834:Lasers; D009391:Nephelometry and Turbidimetry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D041622:Tomography, Optical / Q000295:instrumentation*; D014463:Ultrasonography / Q000295:instrumentation*