A Faraday Isolator (FI) is a nonreciprocal optical device which transmits the linearly polarized light in one direction and deflects the backward beam. It usually consists of a Faraday Rotator and two polarizers. The Faraday Rotator is made of magneto-optical active material which is placed into the permanent magnet system (Nd-Fe-B). Three types of the magneto-optical active materials are available: Terbium-doped glass, Terbium-Gallium-Garnet (TGG) crystals or Yttrium-Iron-Garnet (YIG) crystals.

The FI protects laser by attenuating the reflected and backscattered light by several orders of magnitude (104 to 106). It is also used when some devices have extreme sensitivity to optical feedback which can cause intensity instabilities, frequency pulling and other undesirable effects.

Scientific offers a variety of optical isolator models:

Highly transparent (HT) single stage isolators. Isolation 38-44 dB, wavelength 500-1250 nm (fixed), clear aperture 3-15 mm. Transmission >90%.

Broadband isolators. Isolation >38 dB. Center wavelength - 800 nm (other designs are also available on request). Bandwidth - 130 nm. Clear aperture is 3-12 mm. HT and SE modifications are also available.

Tunable isolators. Peak isolation 38-42 dB. Central wavelength - 780 nm. Tuning range from 700 to 860 nm. Other wavelengths available upon request. Simple and convenient operation.

Single stage isolators with side exit (SE). Isolation 38-44 dB, wavelength from 500 to 1250 nm (fixed), bandwidth - 30 nm. Clear aperture 3-16 mm. Transmission ~85%.

Double stage isolators. Isolation >60 dB. Wavelength is 800 - 1150 nm (fixed). Bandwidth - 30 nm. Clear aperture 3-12 mm.

Isolators for IR optical range. Isolation - 30 dB. Wavelength 1.25 - 3.39 µm (please request, as there are certain restrictions in this range).

Please specify the desired clear aperture, isolator type (above) and wavelength with your enquiry. Please also specify the rod type (TGG or Glass). TGG rods have higher breakdown threshold than Glass rods.