摘要 |
Electro-absorption modulator (EAM), of the kind that includes a waveguide, for modulation of light, comprising a waveguide core, a waveguide cladding (42, 43, 52, 53), and an electrode (45, 55), the modulator being arranged to modulate light launched into the modulator as a response to a voltage being applied on the electrode. According to the invention, the width and/or the thickness of the waveguide core (41, 51) are/is varying along the length of the modulator. The width/thickness is smaller in the portion of the modulator where the light is intended to be input, for the purpose of reducing the absorption of the modulator there. A method in manufacturing of the modulator may utilize a tapered photolithography mask (46).
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