This handbook deals with laser and coherent-domain methods as applied to biomedical diagnostics, environmental monitoring, and materials inspection. It is a second edition of the two-volume Handbook of Coherent-Domain Optical Methods for Biomedical Diagnostics, Environmental and Material Science published by Kluwer Academic Publishers in 2004. The appearance of this book was stimulated by the recent rapid progress in novel photonics technologies on the basis of diode lasers, broadband femtosecond lasers (Ti: Sapphire or Cr: F€orsterite), light-emitting diodes (LEDs), and superluminescence diodes (SLDs). Such technologies are applicable in many fields, namely, biomedical, environmental, and material diagnostics and monitoring. The main ...

We report a method for measuring shear wave velocity in soft materials using phase stabilized swept source optical coherence tomography (PhS-SSOCT). Wave velocity was measured in phantoms with various concentrations of gelatin and therefore different stiffness. Mechanical waves of small amplitudes (∼10 μm) were induced by applying local mechanical excitation at the surface of the phantom. Using the phase-resolved method for displacement measurement described here, the wave velocity was measured at various spatially distributed points on the surface of the tissue-mimicking gelatin-based phantom. The measurements confirmed an anticipated increase in the shear wave velocity with an increase in the gelatin ...

Optical coherence tomography (OCT) is a new, non-invasive, noncontact in vivo imaging technology. We demonstrated that the OCT can be used as a sufficient technique for nanocomposite microcapsule visualization in a liquid medium. As a model system we choose a water/glycerol mixture with viscosity in a variable range from 1.01 to 1.41×103 mPa s, including viscosity of a blood plasma. We have found that tomography spatial resolution is enough to visualize capsules and their aggregates in liquids and to estimate their concentration via two-dimensional (2D) tomography scan analysis. In our experimental conditions microcapsule concentration measured by ...

A big problem in low-coherence interference microscopy is the degradation of the coherence signal caused by shift of the angular and temporal spectrum gates. It limits the depth of field in confocal optical coherence microscopy and degrades images of sample inner structure in most interference microscopy techniques. To overcome this problem we propose numerical correction of the coherence gate in application to full-field swept-source interference microscopy. The proposed technique allows three-dimensional sample imaging without mechanical movement of the microscope components and is also capable of determining separately the geometrical thickness and the refractive index of the sample layers, when the ...

The strong optical scattering of skin tissue makes it very difficult for optical coherence tomography (OCT) to achieve deep imaging in skin. Significant optical clearing of in vivo rat skin sites was achieved within 15 min by topical application of an optical clearing agent PEG-400, a chemical enhancer (thiazone or propanediol), and physical massage. Only when all three components were applied together could a 15 min treatment achieve a three fold increase in the OCT reflectance from a 300 μm depth and 31% enhancement in image depth Zthreshold.

In this paper we present a model of interference microscope image formation, which allows for analysis on unified basis of imaging different types of samples with different interference microscope modalities. The applicability of the proposed model to analysis of the coherence effects, arising in confocal and full-field interference microscopes, when imaging in depth of a layered sample, is shown. The effect of sample transversal structure on the coherence signal is also analyzed, showing that in this case the interference microscope can not be characterized by a single effective aperture and both illuminating and imaging apertures are important.

Optical microscope is a well known instrument with many applications in biomedical imaging and precise measurements. Nowadays a lot of modalities arose, which utilize combination of a microscope arrangement with other optical techniques, such as holography or low-coherence interferometry. The most important features of these modalities are related to the diffraction or coherence effects due to such combination, rather than to exact ways of lens aberrations correction. Therefore for analysis and understanding of these effects a theoretical model is necessary, which would be rigorous enough to take into account the diffraction and coherence effects and in the same time simple ...

Atherosclerosis is the most common underlying cause of vascular disease, occurring in multiple arterial beds including the carotid, coronary, and femoral arteries. Atherosclerosis is an inflammatory process occurring in arterial tissue, involving the subintimal accumulation of low-density lipoproteins (LDL). Little is known about the rates at which these accumulations occur. Measurements of the permeability rate of LDL, and other lipoproteins such as high-density lipoprotein (HDL) and very low-density lipoprotein (VLDL), could help gain a better understanding of the mechanisms involved in the development of atherosclerotic lesions. The permeation of VLDL, LDL, HDL, and glucose was monitored and quantified in normal ...