Raman spectroscopy is a unique optical technique that can probe the changes of vibrational modes of biomolecules associated with tissue premalignant transformation. This study evaluates the clinical utility of confocal Raman spectroscopy over near-infrared (NIR) autofluorescence (AF) spectroscopy and composite NIR AF/Raman spectroscopy for improving early diagnosis of cervical precancer in vivo...

Maxwellite NaFe(3+)(AsO4)F is an arsenate mineral containing fluoride and forms a continuous series with tilasite CaMg(AsO4)F. Both maxwellite and tilasite form a continuous series with durangite NaAl(3+)(AsO4)F. We have used the combination of scanning electron microscopy with EDS and vibrational spectroscopy to chemically analyse the mineral maxwellite and make an assessment of the molecular ...

Pigmented tissues are inaccessible to Raman spectroscopy using visible laser light because of the high level of laser-induced tissue fluorescence. The fluorescence contribution to the acquired Raman signal can be reduced by using an excitationwavelength in the near infrared range around 1000nm. This will shift the Raman spectrum above 1100nm, which is the principal upper detection limit for sil...

We report on the first observation of Raman lasing near 630 nm from 532-nm-pumped, glycerolwater microdroplets on a superhydrophobic surface. Results of cavity-enhanced Raman scattering and Raman lasing experiments are described. ©2008 Optical Society of America OCIS codes: 140.3550 Lasers, Raman; 350.3950, Micro-optics; 230.3990, Microstructure devices; 230.5750, Resonators; 190.5650, Raman Ef...

We propose and apply a theoretical description of a Raman amplifier based on the vector model of randomly birefringent fibers to the characterization of Raman polarizers. The Raman polarizer is a special type of Raman amplifier with the property of producing a highly repolarized beam when fed by relatively weak and unpolarized light.

Electric field polarization orientations and gradients close to near-field scanning optical microscope (NSOM) probes render nano-Raman fundamentally different from micro-Raman spectroscopy. With x-polarized light incident through an NSOM aperture, transmitted light has x, y and z components allowing nano-Raman investigators to probe a variety of polarization configurations. In addition, the str...

The enhancement of a dissolved chemical's Raman scattering by a liquid-core optical fiber (LCOF) geometry is absorption dependent. This dependence leads to a disruption of the usual linear correlation between chemical concentration and Raman peak area. To recover the linearity, we augmented a standard LCOF Raman spectroscopy system with spectrophotometric capabilities, permitting sequential mea...

An optical trap has been combined with a Raman spectrometer to make high-resolution measurements of Raman spectra of optically-immobilized, single, live red (RBC) and white blood cells (WBC) under physiological conditions. Tightly-focused, near infrared wavelength light (1064 nm) is utilized for trapping of single cells and 785 nm light is used for Raman excitation at low levels of incident pow...

Advances in instrumentation are making Raman spectroscopy the tool of choice for an increasing number of (bio)chemical applications. Raman is an interesting option for several reasons, including the sensitivity to small structural changes, non-invasive sampling capability, minimal sample preparation, and high spatial resolution in the case of Raman micro-spectroscopy. Herein we discuss the most...