The 2.5 Gb/s bias-ready modulator is a digital device in which the bias point of the interferometer is set using an applied voltage, typically with a control loop, to operate at the half-intensity point (quadrature). This design uses our x-cut technology, which has been field-proven and provides the best stability in the bias point over life. The device provides superior signal quality across a wide range of wavelengths in the C and L bands and can be used to modulate tunable lasers. The modulator is designed for medium- and long-haul transmission in dense wavelength division multiplexing (DWDM) and time division multiplexing (TDM) systems.