An optical buffer device includes plural optical memory elements that are
capable of holding light and an optical delay element. The plural optical
memory elements are arranged on an optical path through which signal
light and control light propagate in mutually opposite directions.
Further, the optical delay element is disposed between the optical memory
elements that are adjacent to each other. The optical delay element
imparts different delays to the signal light and the control light.
According to a preferred exemplary embodiment of this optical buffer
device, each of the optical memory elements includes an optical waveguide
through which the signal light and the control light propagate and an
optical resonator that is disposed in proximity to this optical
waveguide, and a coupling between the optical waveguide and the optical
resonator is generated or cancelled depending on whether or not the
control light is inputted.