Patent attributes
A small-scale VOA system includes a polarization rotator, a voltage multiplier circuit, and at least one transistor. The polarization rotator can be positioned within a TOSA along the emission axis of a corresponding optical signal source in addition to one or more polarizers. A microcontroller provides a first low voltage control signal to a voltage multiplier to generate a large voltage DC signal which is provided to the transistor. The transistor modulates the large voltage signal with a second control signal from the microcontroller to generate a large voltage AC signal for driving the polarization rotator. The polarization rotation of the polarization rotator can be altered depending on the applied large-voltage AC signal. As a result, the polarization rotator and one or more polarizers can variably attenuate signals emitted by the optical signal source or act as a shutter.
