Química Nova (Jan 2010)

Utilização de um espectrógrafo de projeção como uma ferramenta para demonstrações sobre polarização da luz Projection spectrograph as a tool for light polarization classrooms demonstrations

  • Eduardo Ribeiro de Azevedo,
  • Gregório Couto Faria,
  • Tiago Barbin Batalhão,
  • Jae Antonio de Castro Filho,
  • Ercio Santoni,
  • Josimar Luiz Sartori,
  • Luiz Antônio de Oliveira Nunes

DOI
https://doi.org/10.1590/S0100-40422010000500036
Journal volume & issue
Vol. 33, no. 5
pp. 1204 – 1210

Abstract

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This article describes the use of a projection spectrograph based on an overhead projector for use in classroom demonstrations on light polarization and optical activity. A simple adaptation on a previously developed apparatus allows illustrating several aspects of optical activity, such as circular and linear birefringence, including their wavelength dependence. Specifically, we use the projection spectrograph to demonstrate the optical activity of an aqueous solution of sugar (circular birefringence), of a quartz plate and of an overhead projector transparence film (linear birefringence). A historical survey about the optical activity discovery and the main principles involved is also presented.

Keywords