A method and apparatus is described for controlling the attenuation of multiple
wavelengths signals propagating in an optical fiber, that may have a time-dependent
power in each signal, to provide an output signal having a desired attenuated power
in each of the multiple signals. An equalizer may be used that has various optical
elements to focus and disperse light, such as a concave diffraction grating and
a modulator array having modulators disposed on a concave surface. The equalizer
may also be coupled to various components such as a circulator or thermally expanded
core fibers.
