The 2.5 Gb/s bias-free modulator is a digital device in which the bias point of the interferometer is set to operate at about the half-intensity point (quadrature). A bias control circuit is not required. This feature simplifies circuit design and speeds up product development. 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. As the optical layer extends into the metropolitan and enterprise areas, board real estate is reduced and the component functionality requirement increased. The JDSU miniaturized line of modulators optimizes board space with a footprint reduced by 70%.