Electro-optic phase modulator

An electro-optic phase modulator (100), intended to modulate the optical phase of a lightwave (1) incident on said modulator (100), including:

• an optically transparent electro-optic substrate (110), comprising an entrance face (111), an exit face (112), two lateral faces (115, 116), a lower face (114) and an upper face (113), said lower (114) and upper (113) faces extending between the entrance face (111) and the exit face (112), said upper face (113) being planar and opposite to said lower face (114),
• an optical waveguide (120) that extends, in a plane parallel to said upper face (113), between a guide entrance end (121) located on said entrance face (111) of the substrate (110) and a guide exit end (122) located on said exit face (112) of the substrate (110), said incident lightwave (1) being partially coupled in said optical waveguide (120) into a guided lightwave (3) propagating in an optically guided manner along the optical path of said optical waveguide (120) between said guide entrance end (121) and exit end (122), and
• at least two electrodes (131, 132, 133) that are arranged at least partially along said waveguide (120), parallel to and on either side of the latter, and that define between each other an inter-electrode gap (118), said electrodes (131, 132, 133) allowing to introduce, when a modulation voltage (Vm) is applied between them, a modulation phase-shift, function of said modulation voltage (Vm), on said guided lightwave (3) propagating in said optical waveguide (120),
• characterized in that said optical waveguide (120) has at least one first curved guide portion (124) between said entrance end (121) and said at least two electrodes (131, 132), so that the extension of a direction (121T) tangent to said waveguide (120) on said entrance face (111) deviate from said inter-electrode gap (118).