Optical modulation is to add information to the carrier light wave, so that a certain parameter of the carrier light wave changes with the change of the external signal, including the intensity of the light wave, phase, frequency, polarization, wavelength and so on. The modulated light wave carrying the information is transmitted in the fiber, detected by the photo detector, and then demodulated the required information.
The physical basis of electro-optic modulation is the electro-optic effect, that is, under the action of an applied electric field, the refractive index of some crystals will change, and when the light wave passes through this medium, its transmission characteristics will be affected and changed.
There are many kinds of electro-optic modulators(EO modulator), which can be divided into different categories according to different standards.
According to the different electrode structure, EOM can be divided into lumped parameter modulator and travelling-wave modulator.
According to the different waveguide structure, EOIM can be divided into Msch-Zehnder interference intensity modulator and directional coupling intensity modulator.
According to the relationship between the direction of light and the direction of electric field, EOM can be divided into longitudinal modulators and transverse modulators. The longitudinal electro-optic modulator has the advantages of simple structure, stable operation (independent of polarization), no natural birefringence, etc. Its disadvantage is that the half-wave voltage is too high, especially when the modulation frequency is high, the power loss is relatively large.
Electro-optical intensity modulator is a highly integrated product owned by Rofea with independent intellectual property rights. The instrument integrates electro-optical intensity modulator, microwave amplifier and its driving circuit into one, which not only facilitates the use of users, but also greatly improves the reliability of MZ intensity modulator, and can provide customized services according to user requirements.
Feature:
⚫ Low insertion loss
⚫ High operating bandwidth
⚫ Adjustable gain and offset operating point
⚫ AC 220V
⚫ Easy to use, optional light source
Application:
⚫High speed external modulation system
⚫Teaching and experimental demonstration system
⚫Optical signal generator
⚫Optical RZ, NRZ system
Post time: Oct-07-2023