A small-diameter jet of a transparent liquid having a refractive index greater than the surrounding medium can entrap a light beam and act as an optical fiber. The liquid stream can be bent through quite large angles and will still retain the light. Electrically controlled bending of the liquid stream, and hence the light beam, has been achieved directly by means of electrostatic forces and indirectly by the use of hydraulic devices and associated transducers. Several ways have been demonstrated for separating the light from the liquid stream. The liquid optical fiber principle can be used for building both analog and digital one-or two-dimensional light deflectors.