The central focal masking ("dispersion staining") technique is convenient and effective for determining the refractive index of a microfragment by the immersion method and for distinguishing between minerals in an immersion mount. For most microscopes the only modification needed is the installation of a small opaque dot at or near the focal point of the medium power objective. White light illu...

An electrically controllable fiber Bragg grating (FBG) with polarization-dependent characteristics is described. The optic axis of a liquid crystal (LC) can be rearrangeable by means of external electric fields, which results in the change of an effective refractive index of an LC. The reflectivity and Bragg wavelength of an LC-cladding FBG can be controlled according to the refractive index of...

Optical low-coherence interferometry (OLCI) takes advantage of the variation in refractive index in silicon-wire microring resonator (MRR) effective lengths to perform glucose biosensing using MRR interferograms. The MRR quality factor (Q), proportional to the effective length, could be improved using the silicon-wire propagation loss and coupling ratio from the MRR coupler. Our study showed th...

In the present paper, we describe a new and original method to obtain transparent, siloxane-based composites, with high refractive index (up to 1.68). The method is based on the decomposition of Zn-siloxane, mixed with a poly-(dimethyl)-block-(phenyl)siloxane matrix in different ratios. It was found that after treatment of such mixed metal-containing polymer blend with H2S, the nanoparticles of...

Graphene oxides (GOs) have emerged as precursors offering the potential of a cost-effective and large-scale production of graphene-based materials. Despite that their intrinsic fluorescence property has already brought interest of researchers for optical applications, to date, refractive-index modulation as one of the fundamental aspects of optical properties of GOs has received less attention....

PURPOSE It may be possible to restore accommodation to presbyopic human eyes by refilling the lens capsular bag with a soft polymer. In the present study, optical changes were measured that occurred in a pig eye model after the refilling of the capsular bag. METHODS The optical power and spherical aberration in 10 isolated pig lenses were measured under different conditions. They were first d...

The optical properties of Tl4InGa3S8 layered single crystals have been studied by means of transmission and reflection measurements in the wavelength region between 400 and 1100 nm. The analysis of the room temperature absorption data revealed the presence of both optical indirect and direct transitions with band gap energies of 2.40 and 2.61 eV, respectively. Transmission measurements carried ...