New devices and methods are provided for noninvasive and noncontact
real-time measurements of tissue blood velocity. The invention uses a
digital imaging device such as a detector array that allows independent
intensity measurements at each pixel to capture images of laser speckle
patterns on any surfaces, such as tissue surfaces. The laser speckle is
generated by illuminating the surface of interest with an expanded beam
from a laser source such as a laser diode or a HeNe laser as long as the
detector can detect that particular laser radiation. Digitized speckle
images are analyzed using new algorithms for tissue optics and blood
optics employing multiple scattering analysis and laser Doppler
velocimetry analysis. The resultant two-dimensional images can be
displayed on a color monitor and superimposed on images of the tissues.