Tunable optical filters in 40 Gbps DWDM systems

Tunable optical filters are important components for controlling light in dense wavelength division multiplex (DWDM) systems. They can be used in many optical components, and their tunability can be realized using mechanical equipment, or/and changing the refractive index in transmission media. In DWDM systems several types of tunable filters are used. They are produced with different technologies, and they have different technical parameters, but the most important one is still their price