Refractive Index Of Transparent Liquids Research Articles

A Quantitative Experiment of Liquid Dispersion Using Merely a Partially Submerged Mirror and Sunlight

The refractive index (RI) is probably the single most important parameter in optical systems. Chromatic dispersion, on the other hand, indicates how the RI depends on the wavelength and is central in, e.g., optical communication systems. Chromatic dispersion also plays an important role when teaching optics due to the captivating natural phenomenon of the rainbow and the white light decomposition with a prism. In this work, we propose and explore a method to characterize the refractive index of transparent liquids in the visible range without any dedicated equipment or device (such as prisms, goniometer, laser, detector, etc.).

Instrumentation of the light refraction for measuring the refractive index of transparent liquids

We propose new instrumentation to measure the refractive index (RI) of transparent liquids as a function of temperature. The physical phenomenon used to carry out the measurement is the light refraction that occurs in transparent liquids. A width change in a reference object is produced by light refraction, which is related to the RI. Image processing was used to measure the object width using an image from a digital microscope. The instrument measures the RI from a range of 15°C to 100°C with an accuracy of 10 − 4 % . The measurement procedure was calibrated with distilled water and acetonitrile samples, and the Sellmeier and Cauchy equation was used to compare our results. Finally, as an appropriate application, the RI of lophine in a solution was measured.

Noncontact Optical Fiber Sensor for Measuring the Refractive Index of Liquids

A noncontact optical fiber sensor for measuring the refractive index of transparent liquids is proposed. It operates by calculating the path of a focused laser beam at 635 nm that travels across the boundaries of a liquid sample. The optical power Fresnel reflections are detected and, subsequently, the refractive index is determined as the ratio between the traveled beam paths when the liquid is deposited versus a reference without the liquid sample. Additionally, a mathematical analysis of the geometrical case is included. The theoretical data from our sensor are in good agreement with the experimental results. The resolution achieved by the sensor is better than 10−3 RIU.

Refractive index of a transparent liquid

This article describes an alternative method to determine the refractive index of transparent liquids. The method only requires a laser pointer, a ruler and a modified fish tank.

A single-element interferometer for measuring refractive index of transparent liquids

A simple and stable method based on a single-element interferometer for accurately measuring refractive index of transparent liquids was demonstrated. The refractive index is measured by rotating a rectangular optical glass cell which contains sample liquid and air simultaneously, and by calculating interference fringe shift number which is detected from an interferogram. This method was successfully used to measure the refractive indices of various transparent liquids including distilled water, ethanol and NaCl–water and ethanol–water solutions at various concentrations. The temperature- dependent refractive index of distilled water was also measured. Furthermore, our method is simple to implement, vibration insensitive, and of high accuracy up to 10−4.

Integrated optofluidic index sensor based on self-trapped beams in LiNbO3

We show that self-trapped beams can form in structured monolithic lithium niobate chips. In particular, they are observed to be unaffected when crossing few hundred microns wide gaps. The technique is employed to fabricate an index sensor constituted of a buried circular optical waveguide crossing a fluidic channel in a lithium niobate substrate. Fluidic channels are realized by precision dicing while the optical waveguides are induced by photorefractive beam self-trapping controlled by the pyroelectric effect. The self-aligning property of this latter waveguides provides a simple fabrication technique of an integrated sensor that accurately measures the refractive index of transparent liquids.

Roughened Glass Slides and a Spectrophotometer for the Detection of the Wavelength-Dependent Refractive Index of Transparent Liquids

We describe a method to determine the wavelength-dependent refractive index of liquids by measurement of light transmittance with a spectrophotometer. The method is based on using roughened glass slides with different a priori known refractive indices and immersing the slides into the transparent liquid with unknown refractive index. Using the dispersion data on the glass material it is possible to find the index match between the liquid and the glass slide, and hence the refractive index of the liquid.

Measurement of the difference in the refractive indices of sintered glasses

Methods of measuring the refractive index (RI) of glasses have been known for a long time and are widely used in laboratory practice and in the production of optical glass. These methods have a fairly high accuracy with comparatively simple equipment. The RI of glasses is determined most frequently by means of Pulfrich or Abbe refractometers or by the immersion method. The goniometric method is used to study the optical constants of glasses [i, 2]. In [3] a method is proposed for determining the RI of transparent liquids in a wedge-shaped cuvette by double reflection of a laser beam.

Effect of laser radiation on the refractive index of transparent liquids containing absorbing particles

Theoretical and experimental investigations were made of the effect of laser radiation on the refractive index of transparent liquids containing absorbing particles. A study was made of dependences of the change in the refractive index on the energy density of the radiation, concentration, absorption coefficient, and size of the particles, and also on the sample settling time. It is shown that the kinetics of bubble growth during boiling is governed by the process of heat transfer in the particle–vapor–liquid system and the bubble size increases mainly under gasdynamic equilibrium conditions. It is noted that this effect may be used to observe low concentrations of absorbing particles and also to obtain information on their material and size.

The direct determination of the temperature dependence of the refractive index of liquids and solids

A technique is described which allows a direct determination of the temperature dependence of the refractive index of transparent liquids and solids. It consists of an interferometric examination of a liquid or solid whose temperature changed in time linearly. For all the tested liquids except water, delta n/ delta t was found to be constant in the range 25-60 degrees C. The values delta n/ delta t determined for H2O, C6H12 and CCl4, and the value of delta 2n/ delta t2 obtained for water, are in good agreement with literature.