In this paper an inexpensive optical device is described, which is capable of measuring the optical reflectance at different angles, while keeping the laser spot stationary at one point of the surface. This is accomplished by applying cylindrical optics. Its use is demonstrated in a surface plasmon resonance (SPR) sensor. A coil-operated vibrating mirror is used to obtain an angle scan of about...

Films consisting of amorphous carbon dispersed in tetragonal nanocrystalline zirconia were characterized for their optical properties by reflectance measurements. The optical constants of each component of the composite have been extracted; the experimental reflectance spectra have been fitted to Maxwell-Garnett effective medium theory, leading to the effective dielectric constants of the film....

Reflectance measurements acquired from within the subdiffusion regime (i.e., lengthscales smaller than a transport mean free path) retain much of the original information about the shape of the scattering phase function. Given this sensitivity, many models of subdiffusion regime light propagation have focused on parametrizing the optical signal through various optical and empirical parameters. ...

We have experimentally studied the dispersion of optical conductivity in few-layer graphene through reflection spectroscopy at visible wavelengths. A laser scanning microscope (LSM) with a supercontinuum laser source measured the frequency dependence of the reflectance of exfoliated graphene flakes, including monolayer, bilayer and trilayer graphene, loaded on a Si/SiO2 Fabry-Pérot resonator in...

Moth-eye nanostructures, discovered to coat corneae of certain nocturnal insects, have inspired numerous technological applications to reduce light reflectance from solar cells, light-emitting diodes, and optical detectors. Technological developments require such nanocoatings to possess broadband antireflective properties, transcending the visual light spectrum, in which animals typically opera...

To investigate both the optical and electrical properties of InN, we have measured the infrared reflectance spectra of InN thin films and performed the fitting analyses of the infrared spectra to obtain not only phonon frequencies and the damping factors but also the carrier concentration of InN. In this paper, we extend the aim of those analyses to the electron mobility and demonstrate that th...

It is demonstrated, using reflectance difference spectroscopy, scanning tunneling microscopy, and low-energy electron diffraction, combined with deliberate straining of the surface, that the presence of atomic steps dramatically changes the optical anisotropy of the Si(001) surface. The step-induced reflectance difference signal originates predominately from rebonded steps and is comparable in ...

PURPOSE Developed herein is a three-dimensional (3D) flow contrast imaging system leveraging advancements in the extension of laser speckle contrast imaging theories to deep tissues along with our recently developed finite-element diffuse correlation tomography (DCT) reconstruction scheme. This technique, termed speckle contrast diffuse correlation tomography (scDCT), enables incorporation of c...

When unity reflectance is approached, the Fourier-transform method of calculating the reflectance spectrum of an optical grating modulated by a slowly varying envelope becomes unacceptably inaccurate. The modified Fourier transform method of Bovard [Appl. Opt. 29, 24 (1990)] can achieve complete accuracy for quarter-wave gratings. We report herein the extension of Bovard's method to non-quarter...

We describe a system for rendering bubbles in natural environments using filtered environment maps. The system incorporates the optical properties of soap bubbles such as the interference patterns generated by the film. We describe a mathematical model to simulate the reflectance properties of the bubbles using a bidirectional reflectance field. This BRDF is used to filter an environment map ca...