The MDL Series Motorized Variable Optical Delay Lines provide precision optical path delays of up to 17 cm, which corresponds to 560 picoseconds maximum delay in the time domain. Driven by a DC motor with an integrated encoder, the motorized variable optical delay line offers a high delay resolution of 1 fs for both 330 and 560 pico-second models. These motorized optical delay lines employ a compact and rugged package design that makes the device ideal for network equipment and test instrument integration. The delay lines can also be used in laboratories for precision optical path length control or timing alignment. The major applications include optical coherence tomography (OCT), time division multiplexing (TDM), pulse alignment, optical spectrum analysis, and interferometry. The MDL Series can also be used to vary the modulation phase of reflections for the testing of reflection effects on transmitters.