Refractive Index Measurement and its Applications

Abstract

The refractive index of a material is one of the most important optical parameters. In this review article we have discussed different methods and techniques for the measurement of refractive indices of various materials. We have considered the literature of the past two decades from 1980 to 2001 and have shown how the techniques have been developed and improved for the measurement of refractive indices. Some applications of refractive index have also been discussed.

Refractive-index determination of solids from first- and second-order critical diffraction angles of periodic surface patterns

“…1,2 Hence, new methods for its determination are still being devised today, 3 many of which are optimized for a particular type of application. In liquids, the refractive index can be measured precisely with common techniques 4 which, however, become demanding when applied to solids. The Abbe refractometer, for example, often requires index-matching fluids of high refractive index to optically couple the solid sample to the prism.…”

Microfluidic integration of porous photonic crystal nanolasers for chemical sensing

“…Although the is significantly less than what can be measured by state-of-the-art measurement systems [19], the PPC offers another significant measurement tool for the lab-on-a-chip. As described above, the emission wavelength of the PPC laser is a function of the material and the geometry of the lattice.…”

Group refractive index reconstruction with broadband interferometric confocal microscopy

“…The illumination beam in V has a field denoted by u 0 (r;k). The field is given in terms of its Fourier spectrum at the beam waist plane z =0: (3) where B(q′/k) is the Fourier expansion of the beam field in the plane z=0, and . The scaling and normalization with k ensures that the beam amplitude at the focus is the same for all frequencies k. For a Gaussian beam, B(q′/k) = B 0 exp(−q ′ 2 α 2 /2k 2 ), where α=π/NA, and NA is the numerical aperture of the focusing of the lens.…”

“…The spatial refractive index distribution determines the behavior of many optical phenomena, including scattering processes and light-induced surface forces, which in turn are relevant to an array of optical sensing, imaging, and manipulation techniques [3]. For example, scattering processes arising from cellular and subcellular refractive index discontinuities are key to diagnostic techniques like diffuse optical tomography and optical coherence tomography [4,5].…”