User:Gb Arivazhagan/Interferometric laser imaging for droplet sizing

Interferometric Laser Imaging for Droplet Sizing or ILIDS is a technique used for characterizing sprays. It is based on Mie Scattering theory. When, a coherent laser source is used to illuminate the droplets, the interference of scattered light from the droplet is considered In the scatter diagram, oscillating lobes are found in wide angle forward scatter region around 40° to 70°. It arises because of the interference between reflected ray and first order refracted ray and the contributions from higher order refracted rays are negligible in the forward scattering region. Based on optical calculations, it is concluded that the angular frequency of fringes is directly proportional to the droplet diameter and hence can provide accurate measurement of droplet size. The technique has its origins in Konig et al. (1986), who focused a single laser beam onto a stream of mono dispersed droplets and measured the resulting fringe pattern in the far field. It was recognized that, this technique had the potential for highly accurate size measurements and applied the technique to measure droplet evaporation. Ragucci et al. (1990) also examined the case of scattering from a single droplet using a Lorenz–Mie calculation to find the oscillation behaviour of the scattered intensity in the far field. Glover et al. (1995) made an extension to the technique by using an illuminated laser sheet and examined the sparse injection sprays in an optical internal combustion engine. They named the technique Interferometric Laser Imaging for Droplet Sizing or (ILIDS).