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The purpose of this paper is to discuss the light scattering of nonspherical particles that is very important for the research on the aerosol optical properties.

In this paper, the authors use the spheroid model as the characteristic particle shape to study the single scattering albedo of real nonspherical particles. Meanwhile, the extinction and scattering cross section of spheroids are calculated with the T matrix method combined with the improved geometric optics approximation method (IGOM).

Through this combination, the extinction and scattering cross section of spheroids can be obtained in the larger size range and aspect ratio range. Furthermore, the comparison of the single scattering albedo for the spheroids and their equivalent spheres is conducted in order to investigate the difference of the spherical and nonspherical particles.

Simulation experiments indicate that the single scattering albedo of spheroids can be calculated well with this combination, and it has some obvious influence on the variation of the aspect ratio, incident wavelength, and complex refractive index of spheroid particles.

This paper aims to reports the further developments of an optical sensing technique, relying on Mie scattered and reflected light, from the ice surface and volume, to determine the ice accretion rate as well as the ice type.

By measuring the optical intensity of the backscattered and reflected light, the paper demonstrates that it is possible to obtain information on the onset of icing as well as determine the thickness and type of ice accreted on the leading edge of a wing in real time.

This work is important in the design and development of optical direct ice detection sensors for aerospace applications.

This work is aimed at showing a new approach to ice detection.

Original concept follow on paper from pervious publication.

Outlines research work into the assessment of light‐scattering techniques for manufactured surfaces inspection. Describes the three type of commercial sensors that have been available so far: glossometers, peak intensity meters and light distribution measuring instruments and how they work. Describes the laboratory rig supporting equipment and analysis methodologies employed in order that numerous surfaces could be examined and classified. The outcome was an atlas of typical manufactured surfaces and a small ruggedized test bed sensor. Concludes that by using this rig and the atlas the whole 3‐dimensional light scatter image can be examined to select the appropriate sensor.

The effects which are produced by pearlescent pigments are intimately connected to optics and the interaction of light with matter. Pearlescent pigments are optical filters which reflect and transmit light which falls upon them. In order to understand pearlescent pigments, therefore it is first necessary to understand some of the basic laws of optics. I would like to review some of these laws to talk about light and its interaction with matter, how it can be separated into its components, the laws of reflection and refraction and how all of these laws apply to pearlescent pigments.

Physical bases of light scattering by cylinders are discussed. Method and apparatus for measuring the scattered light flux distribution with angle are described. The unnormalized angular distribution of relative fibers length for fibrous structures with low optical density is verified to be in agreement with experimental results. The experimental reliability is discussed in terms of apparatus performance and fibrous sample parameters.

There are various temperature measuring systems presented in the literature and on the market today. Over the past number of years a range of luminescent‐based optical fibre sensors have been reported and developed which include fluorescence and optical scattering. These temperature sensors incorporate materials that emit wavelength shifted light when excited by an optical source. The majority of commercially available systems are based on fluorescent properties.Design/methodology/approach – Many published journal articles and conference papers were investigated and existing temperature sensors in the market were examined.Findings – In optical thermometry, the light is used to carry temperature information. In many cases optical fibres are used to transmit and receive this light. Optical fibres are immune to electromagnetic interference and are small in size, which allows them to make very localized measurements. A temperature sensitive material forms a sensor and the subsequent optical data are transmitted via optical fibres to electronic detection systems. Two keys areas were investigated namely fluorescence based temperature sensors and temperature sensors involving optical scattering.Originality/value – An overview of optical fibre temperature sensors based on luminescence is presented. This review provides a summary of optical temperature sensors, old and new which exist in today's world of sensing.

The harsh environment of space, especially radiation of direct solar rays, can potentially raise the temperature of the spacecraft to harmful levels. Thermal control coatings (TCCs) fix the thermal condition of the spacecraft acceptable for its components. This is possible by diffusely reflecting all effective ultraviolet (UV), visible (VIS) and near infrared (IR) (NIR) wavelengths of solar radiation and emmition of IR energy. The most commonly used TCCs have used ZnO as a pigment, but absorption of the UV light by ZnO pigment can change the ideal condition of these TCCs. The aim of his study is the using the porous ZnO particles as pigment to prevent the UV absorption.

To enhance the efficiency of these coatings, in the present study, nano-porous zinc oxide particles were synthesized and used as pigments for white TCCs.

The results revealed that the proposed TCC (TPZ), Thermal control coating with porous ZnO had better reflection (scattering) and emittance properties in comparison with the coating using ZnO as a pigment (TZ coating); so this coating had a solar absorptance value equal to 0.141, whereas this value for TZ was 0.150. Furthermore, TPZ showed higher thermal emittance (0.937) in comparison with TZ (0.9). These changes were because of the improvement in the refractive index, shape and surface area of the pigments. The general trend of the scattering coefficients for the prepared coating, as calculated from the Kubelka–Munk equation, showed that scattering was more efficient in the UV region, as compared with the TCC containing ZnO pigments.

This type of pigment for the first time is evaluated in TCCs.

The behaviour of light in white prints is dominated by the presence of titanium dioxide pigment, which is responsible for opacity. The pigment also strongly influences gloss and is responsible for the whiteness of prints.

Laser‐scattering techniques have aided the correct orientation of mechanical components in automatic assembly. The same techniques can also lend themselves to certain types of inspection.

This paper aims to present a review of the design and development of the turbidimeter for measuring the turbidity level in water. Monitoring the turbidity level of water is important because it is related to public health.

A precise and reliable turbidimeter can provide vital data that reveals the water condition level. Several turbidimeter units are discussed briefly. Three types of turbidimeter design – single beam, ratio and modulated four beams – are elaborated with some illustrations of the design concept. Various improvements and innovations for upgrading turbidimeter design are also discussed.

This paper elaborated on a new method of estimating the water turbidity level in water samples using an optical tomography system based on the independent component analysis method. The results showed that a tomography-based turbidimeter can measure slight changes in the level of turbidity when the volume of contaminants is changed slightly. The turbidimeter can also provide a profile of the distribution of the turbidity in the water sample.

A turbidimeter based on the optical tomography concept can be a valuable tool in determining the level of pollution in rivers, sea, etc.