A New Double Beam Optical Lever Refractometer and the Variation of the Refractive Index of NaCl with Temperature

Abstract

The design and construction of a double beam optical lever are described. Its use is illustrated by describing an experiment to measure changes of the order of 10−5 in the refractive index of NaCl by the method of measuring the change in angle of refraction of a beam of light by a prism of the salt. It is capable of higher sensitivities and has the advantage that it can monitor the motion of the crystal as a whole.

A simple multipurpose double-beam optical image analyzer

“…It can be performed using either a beam splitter [1][2][3][4] or a dichroic mirror. [5][6][7] While the first one allows for spreading the light with a given proportion and in a wide wavelength range, the latter exposes wavelength dependent reflection characteristics.…”