▎ 摘　　要

NOVELTY - The modulator has a lower cladding layer formed on a substrate. A waveguide core layer and the lower cladding layer are attached together to form a ridge structure. An ITO transparent electrode is fixed on the waveguide core layer. A cover is exposed at surface of the lower cladding layer. A lower insulating medium layer is provided with the ITO transparent electrode. The insulating medium layer is provided with a monolayer graphene thin film. A high-refractive index silicon oxide layer is provided with the insulating medium layer. USE - Low refractive index difference waveguide graphene modulator. ADVANTAGE - The modulator has small volume, wide bandwidth, small insertion loss and simple technique. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a low-refractive index difference waveguide graphene modulator preparing method. DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of a low-refractive index difference waveguide graphene modulator.