Oregon Medical Laser Center Newsletter. Jan 1998. Steven Jacques.
This month we emphasize laser speckle.
The purposes of this gallery are:
Links are provided to the websites and viewers are encouraged to visit the original sites which have more pictures, discussions, references to papers, job opportunities, software, lists of staff, etc.
Laser speckle is an indicator for motion.
Figure 1: (A) Speckle pattern from a stationary block of titanium dioxide in epoxy resin observed with a CCD camera from above. The fine pattern of light and dark spots is the speckle pattern, an interference pattern of photons backscattered from the block. (HeNe laser, 632.8 nm).
(B) Image of same block while being moved by hand during the 0.1-s integration time of the CCD camera. The speckle intensities appear to fluctuate and the time averaging of this fluctuation during the camera integration time yields a field of "grey" pixels.
The Oregon Medical Laser Center and the Dental School at the Oregon Health Sciences University are investigating the use of speckle to characterize the mechanical properties of biological tissues. Applications in dermatology, dentistry, and cardiology are being studied.
Oregon Medical Laser Center