Pellin polarimeter, paris
A ph. & f. Pellin, paris polarimeter, c 1900. Many substances have the property, called optical activity, of rotating the plane of polarization of the light that has passed though a sample. The amount of rotation depends on the thickness and the concentration of the sample and therefore one can learn various properties of a sample by measurements of its polarization. A polarimeter enables one to do that by the use of nicol prisms at both ends. This polarimeter has a glass tube about 58 cm long through which the polarized light passes. At the other end is a polarization detector that is rotatable to measure the change in angle. The signature reads ph & f. Pellin paris. The height is adjustable. The angle scale range is 100Ã‚Â°-0-100Ã‚Â° and is about 28 cm in diameter.