polarisationsempfindliche

Polarisation, or polarization, refers to the orientation of the oscillation of a transverse wave, most commonly light. In optics, polarization describes the direction of the electric field vector of the electromagnetic wave as it propagates. Unpolarised light consists of many waves with random orientations, while polarised light has a preferred orientation or state.

Common states are linear, circular, and elliptical polarization. Linear polarization confines the electric field to a single plane. Circular polarization results when two orthogonal components have equal amplitudes and a 90-degree phase difference, producing a rotating electric field; left-handed and right-handed circular polarization denote the sense of rotation. Elliptical polarization is the general case and includes linear and circular as special limits.

Generation and manipulation rely on optical elements. Polarizers transmit only a chosen polarization component; waveplates introduce phase shifts between orthogonal components; polarizing beam splitters separate polarizations. Polarisation can also arise from reflection, refraction, scattering, and birefringence in anisotropic materials; Brewster's angle is a notable case where reflected light is polarized.

Measurement and analysis use polarimetry and Stokes parameters, which describe the state of polarization. The Poincaré sphere provides a geometric representation of polarization states. Ellipsometry characterizes changes in polarization upon reflection and the properties of surfaces.

Applications span photography and display technology, where polarizers improve contrast; liquid crystal displays rely on controlled polarization; polarization multiplexing is used in optical communications; photography, 3D cinema, remote sensing, and astronomy exploit polarization to reveal material properties and magnetic fields. In radio and microwave engineering, polarization of antennas affects transmission efficiency and reception; circular polarization can reduce multipath fading.