Pō'lar-ĭ-zā'tion, n.

n. [Fr. polarisation, Sp. polarizacion, It. polarizzazione.] The act of polarizing; the state of being polarized, or of having polarity.

Angle of polarization. Circular polarization. Elliptic polarization. Plane of polarization. Plane polarization. Polarization of light. Polarized light. If a beam of light, which has been reflected from a plate of unsilvered glass at an angle of about 56°, be received upon a second plate of glass similar to the former, and at the same angle of incidence, the light will be readily reflected when the two planes of incidence are parallel to each other, but will not be reflected when the two planes of incidence are perpendicular to each other. The light has, therefore, acquired new properties by reflection from the first plate of glass, and is called polarized light, while the modification which the light has experienced by this reflection is called polarization. The plane in which the beam of light is reflected from the first mirror is called the plane of polarization. The angle of polarization is the angle at which a beam of light must be reflected, in order that the polarization may be the most complete. The term polarization was derived from the theory of emission; and it was conceived that each luminous molecule has two poles analogous to the poles of a magnet. Light may be polarized in several other methods, as by refraction through most crystalline media, or by being transmitted obliquely through several plates of glass with parallel faces. If a beam of polarized light be transmitted through a crystal of quartz in the direction of its axis, the plane of polarization will be changed by an angle proportional to the thickness of the crystal. This phenomenon is called circular polarization, while the polarization first described is called plane polarization. A beam of light reflected from a metallic surface acquires properties still more complex, to which the name of elliptic polarization has been given. Loomis.