Raman spectroscopy has been considered like a potentially important clinical tool for real-time diagnosis of disease and evaluation of living tissue, whit the proposal to development noninvasive glucose measurements in a near future, with lower power than other reported studies, in this work are reported experimental tests made with a excitation source of semiconductor laser of 785 nm and 35 mW power.<p> </p> Measurements were made to different glucose concentrations, with variation from 50 mg/dL to 6000 mg/dL. For this, three intervals with different ranges of concentration were analyzed, these tests were put into plastic sampling cells, making incise the beam vertically on sample. In the same way measurements to serum human are reported, for healthy volunteers had 12 hours fasting and non-fasting conditions, with it's corresponding values of glucose taken through a conventional glucometer.<p> </p> Freeze-dried human serum was poured on object-holder, in the case of human serum reconstitute, it was used container in which were previously kept samples. Nine spectra per test were obtained and subsequently average was calculated, the spectra were studied in a range of 500 to 1700 cm<sup>-1</sup>. This work explores the intensity variation of the bands of glucose in 1065 cm<sup>-1</sup> and 1127 cm<sup>-1</sup> as a function of glucose concentration. In the obtained results, there observes a behavior with positive slope in both substances, interrelation being observed between the measurements, being promissory for non-invasive measurement.
This document presents a first approach to study the behavior of a static fluid radiated by infrared light (980nm,100mW) transmitted by a single-mode optical fiber, for this simulation temperature and radiation pressure are calculated based on the intensity delivered by a laser diode. The Computing Fluid Dynamics (CFD) results were based on a mesh Tet/Hybrid, TGrid for a Silica micro-particle and a mesh Hex/Wedge, Cooper for the beam. The results show that as the particle moves along the axis, temperature and pressure decreases, having the points of mayor temperature and pressure around the axis. The conclusion of this work is that it is possible to simulate the interactions between the beam, the micro-particle and the surrounding medium in terms of temperature, velocity and pressure using the energy and viscous model.
An optical fiber trap operates by radiation pressure and transverse force gradient while conventional optical trap operates on longitudinal gradient to trap particles. This subtle difference translates into easy setup and many advantages over conventional single-beam optical tweezers. In this work, we present a brief review of the current situation of fiber optic trap and their applications. Subsequently, we discuss the effect of radiation pressure on micro-organic and inorganic particles. Using a single optical fiber, radiation pressure transfers movement to the micro-particles, so velocity and acceleration are quantified. After that, micro particles are trapped, but now using two optical fibers. Finally, we discuss the results and problems involved with this research.
A comparative analysis of ultraviolet light absorption is presented for distinct photosensitive optical fibers. Fibers are
irradiated by ultraviolet light, coming from a pulsed Nd:YAG Laser (90 mJ, 5-7 ns) at 266 nm. Absorption is analyzed
from ultraviolet to infrared region and it is compared for different photosensitive optical fibers. The final goal of this
work is to identify absorption spectral regions, which would be useful in order to improve fiber grating printing.
Speckle interferometry is a powerful and basic technique to test mechanical parameter. Traditional speckle
interferometry is implemented in laboratory, with bulk components. On the other hand, real applications demands of
more practical set-ups: compact and robust. Optical fibers present a possibility to substitute some bulk components
and to access far and adverse mediums. Based on our experimental experience we discuss the advantages and
disadvantages in the implementation of optical fiber in speckle interferometry. In order to observe high constrast of
fringes; we tested different and conventional fiber. We compare results from different types of fibers and discussed
the viability to implement it in optical speckle interferometry.
It has been recently shown that application of Michelson interferometry, is suitable for monitoring of oxide layers
growing in metallic structures during preliminary states of oxidation processes in aqueous solutions, without any
physical contact with the sample. The qualitative and quantitative interpretation of the observed interferograms allows
evaluation of important physical parameters related to specific corrosion processes . Although the using of aluminum
samples with surfaces polished to certain optical quality is a necessary requirement to obtain well-built interferograms, it
complicates further applications for diffused surfaces typical of industrial conditions. In this work we present preliminary
qualitative results obtained by using a simple experimental setup based on Digital Speckle Pattern Interferometry (DSPI)
, as a proposal to solve this difficulty and on the other hand, to use the benefits of certain powerful tools like low-coherence
optical techniques for further applications on monitoring of corrosion through turbid media.
We proposed a method for the 3D position estimation in particle image velocimetry. The method uses the pattern-matching between theoretical and experimental images by exploiting the scattered energy field and uses genetic algorithm. The simulations and experimental verification of this problem are discussed.