Image Number 19 for United States Patent #6392807.
The present invention provides an improved tunable chromatic dispersion compensator. The compensator includes: a virtually imaged phased array (VIPA); at least one reflector optically coupled to the VIPA; a mirror optically coupled to the at least one reflector; and a movable reflector holder coupled to the at least one reflector, where the movable reflector holder moves the at least one reflector such that a length of a beam path between the VIPA and the at least one reflector and the mirror is variable. The present invention uses the VIPA to produce a controlled variable degree of chromatic dispersion within a plurality of optical channels so as to compensate for unwanted chromatic dispersion in an optical communications system. Positional adjustment of the movable reflector holder permits variable control of the beam path length between the VIPA and the focusing lens. This variable change in beam path length permits variable control of the magnitude and sign of chromatic dispersion provide by the compensator.