The present invention relates to an optical waveguide type synaptic weight modulator with a nematic liquid crystal cladding layer. The modulator can be used for optronics and optical neural computing. The modulator includes a multichannel waveguide provided on a glass substrate, electrodes which are provided on the glass substrate and which sandwich the channels of the waveguide, a nematic liquid crystal cladding layer provided perpendicularly to the waveguide and electrodes, a control power supply connected to the electrodes, a light source prism coupled to the waveguide, and a multimode fiber end surface coupling an output of the waveguide to a photomultiplier. The nematic liquid crystal cladding layer provides an electrooptical effect and is fixed by an orientation film. Weights are added to each signal in the same manner as the synaptic action of a neural circuit by controlling the power distribution of an input signal consisting of a combination of different waveguide modes by an electric deflection effect with respect to a liquid crystal molecular direction.
Optical waveguide type synaptic weight modulator with nematic liquid crystal cladding