Optical modulators convert information carried by an electric current in an electromagnet into light. According to the properties of the material that are used to modulate the light beam, modulators are divided into two groups: absorptive modulators and refractive modulators. The beam may be carried over free space, or propagated through an optical waveguide (optical fibre). In this. Optical modulation is a process of modifying light waves according to high-frequency electrical signals that contain information.
[pdf] According to the properties of the material that are used to modulate the light beam, modulators are divided into two groups: absorptive modulators and refractive modulators. In absorptive modulators the of the material is changed, in refractive modulators the of the material is changed. The absorption coefficient of the material in the modulator can be manipulated by the.
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