Abstract: Methods and apparatus for polarizing un-polarized laser light by passing a beam of un-polarized laser light through an isotropic, right-angle prism having a dielectric coating on its hypotenuse incident upon the coated hypotenuse at an angle of incidence less than the critical angle wherein the net-refractive index of the coating and angle of incidence on the hypotenuse are mutually selected to achieve maximum separation of the S and P constituents of the beam with a maximum percent of the S-constituent internally reflected and a maximum percent of the P-constituent transmitted through the coated hypotenuse.

Abstract: A Faraday rotator for rotating a plane of polarization of polarized light, said Faraday rotator having an optical element comprising a rod which is comprised of an optically transmitting composition comprising cadmium, zinc, and tellurium, and preferably from about 30 wt. % to about 48 wt. % cadmium, from about 2 wt. % to about 20 wt. % zinc, and about 50 wt. % tellurium. This Faraday rotator is especially useful an optical isolator for preventing feedback of transmitted light waves.

Abstract: An improvement in a method of rotating the plane of polarization of polarized light in a Faraday rotator, having an optical element which includes a ferromagnetic material, which comprises varying the strength of the magnetic field generated along the optical axis of the optical element in response to changes in the wavelength of the polarized light. The magnet employed in the Faraday rotator may be at least one permanent magnet or an electromagnet. Preferred optical elements are made of disc having a gadolinium-gallium-garnet (GGG) or large lattice constant (LLC) substrate, and the substrate is coated with an oxygen--and iron--containing film.

Abstract: A Faraday rotator having a first, or central magnet, and first and second tuning magnets a opposite ends of the central magnet. The central magnet and the tuning magnets are of opposite polarities. The central magnet surrounds a first optical element having a positive or negative Verdet constant, and the tuning magnets surround second and third optical elements, respectively. The second and third optical elements each have a Verdet constant of a sign opposite that of the first optical element. Such Faraday rotators require smaller magnet assemblies than Faraday rotators having just one optical element surrounded by the central magnet. There is also provided a Faraday rotator having at least two magnets wherein each magnet of any one pair of contiguous magnets generates a magnetic field in a direction opposite that generated by the other of the any one pair of contiguous magnets. The optical elements surrounded by these magnets have oppositely signed Verdet constants.

Abstract: A Faraday rotator having an optical element and a donut magnet of length 1.0L for generating a magnetic field along the optical axis of the optical element in order to rotate a plane of polarization of polarized light. At each end of the donut magnet of length 1.0L is a tuning magent of a length from about 0.4L to about 0.7L, with each of said tuning magnets generating a magnetic field in a direction opposite to that of the donut magnet.

Abstract: A Faraday rotator for rotating a plane of polarization of polarized light, said Faraday rotator having an optical element comprising a rod which is comprised of an optically transmitting composition comprising from about 15 wt. % to about 50 wt. % germanium, from about 5 wt. % to about 20 wt. % arsenic, and from about 30 wt. % to about 80 wt. % selenium. This Faraday rotator is especially useful in an optical isolator for preventing feedback of transmitted light waves.

Abstract: A Faraday rotator comprising an optical element having an optical axis, a means for generating a magnetic field along the optical axis of the optical element in order to rotate a plane of polarization of polarized light about the optical axis, and a means for moving said optical element such that varying portions of the optical element can be enclosed over or withdrawn from the means for generating a magnetic field. In a preferred embodiment the optical element is held within a clamp contained within a movable screw which can be turned so as to vary the amount of the optical element surrounded by the means for generating the magnetic field.