4 March 1999 Transform method for laser speckle strain-rate measurements in biological tissues and biomaterials
Author Affiliations +
Proceedings Volume 3726, Saratov Fall Meeting '98: Light Scattering Technologies for Mechanics, Biomedicine, and Material Science; (1999) https://doi.org/10.1117/12.341432
Event: Saratov Fall Meeting '98: Light Scattering Technologies for Mechanics, Biomedicine, and Material Science, 1998, Saratov, Russian Federation
Abstract
Laser speckle strain measurements in biological tissues and some synthetic biomaterials, such as translucent dental composites and ceramics, are often complicated by the physical properties of the materials. For example, speckles generated by illuminating soft biological tissue with laser light are subject to rapid decorrelation due to the Brownian movement of water and scattering particles in the tissues and to cellular motions. In addition, the penetration of the laser beam into the tissue or translucent biomaterial results in multiple scattering and a complete depolarization of the speckle field. This may complicate the evaluation of the strain field when a force is applied to the material because the speckle pattern shift is providing information from the surface of the material as well as from the bulk sample, where the strains may or may not be the same as on the surface. This paper presents a variation of a speckle processing scheme originally called the `Transform Method' for evaluating both surface and bulk strain rates and total strains in biological tissues and translucent biomaterials. The method is not a correlation-based technique, but instead relies upon 2D frequency transforms of time series of 1D speckle pattern records stacked into 2D arrays. The method is insensitive to speckle field depolarization and, compared to correlation-based techniques, is relatively insensitive to speckle decorrelation. Strain rates and total in-plane strains were measured in both hard (cortical bone) and soft (artery segments) biological tissues and in translucent biomaterials (dental ceramics). Potential applications to medical diagnostics and biomaterials science are also discussed.
© (1999) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Sean J. Kirkpatrick, Sean J. Kirkpatrick, } "Transform method for laser speckle strain-rate measurements in biological tissues and biomaterials", Proc. SPIE 3726, Saratov Fall Meeting '98: Light Scattering Technologies for Mechanics, Biomedicine, and Material Science, (4 March 1999); doi: 10.1117/12.341432; https://doi.org/10.1117/12.341432
PROCEEDINGS
8 PAGES


SHARE
Back to Top