An optical switch comprises a two-dimensional array of optical inputs, a Fourier transform lens, and a two-dimensional array of optical outputs. Each of the optical inputs emits an optical beam that is transmitted through the Fourier transform lens to one of the optical outputs. A first deflection means gives each of the optical beams a respective direction of incidence upon the Fourier transform lens. The optical output to which a given beam travels depends on the beam's respective direction of incidence. A second deflection means deflects the optical beams after they have been transmitted through the Fourier transform lens and renders the beams parallel, thereby enabling the beams to couple efficiently to the optical outputs. Each of the deflection means preferably comprises at least one Micro-Electro-Mechanical Systems, or MEMS, deflector array. The optical inputs and outputs preferably comprise optical fibers. The Fourier transform lens overcomes diffraction limitations, since the lens causes the spreading optical beams to reconverge.