G02F1/00

Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics [1, 2, 4, 2006.01]

Note(s) This group covers only:[2] devices or arrangements, e g  cells, the optical operation of which is modified by changing the optical properties of the medium of the devices or arrangements by the influence or control of physical parameters, e g  electric fields, electric current, magnetic fields, sound or mechanical vibrations, stress or thermal effects;devices or arrangements in which the electric or magnetic field component of the light beams influences the optical properties of the medium, i e  non-linear optics;control of light by electromagnetic waves, e g  radio waves, or by electrons or other elementary particles