New design of spectropolarimeter

Precise measurement of the refractive index and optical rotatory power of a suspension by a delayed optical heterodyne technique

By using an optical heterodyne technique, we have demonstrated the detection of ballistic photons traveling through a suspension. We measured the propagation time of light in a sample with a variable optical delay line in the reference arm of an interferometer, using a superluminescent diode as a light source. The resolution and accuracy in propagation time measurement were 400 and 3 fs, respectively. The minimum detectable rotation angle of 1/10,000 deg was achieved with an integration time of 5 s. This system can measure the refractive index and optical rotatory power of the suspension in a solvent without disturbing heavy scattering from particles in the suspension, because ballistic photons are detected.

An automatic recording magnetooptical rotation spectropolarimeter

The design and construction of an automatic recording spectropolarimeter for measuring magnetooptical rotations (Faraday effect) in a magnetic field is described. The instrument has two opposed 5000 G magnetic fields (one for solution and one for solvent) to give solute rotation directly as a function of wavelength (250-750 mmicro;) to a precision of +/-0.001 degrees in the visible and +/-0.003 degrees in the uv region of the spectrum. A description of the instrument performance and typical spectra is given.