Nortel Networks Corporation

Northern Telecom Limited

Steven P McGarry

Charles D MacPherson

Bruce C Beggs

Rivaz Jamal

An adaptive optical waveguide router in which routing paths may be dynamically created by the use of a scanning system. The optical router interconnects at least one optical input to a at least optical output. The optical waveguide layer employed is substantially comprised of a photosensitive material which has a change in index of refraction at one optical wavelength when exposed to a different optical wavelength and which, in some way, may be restored to it's original state. One such material is Bacteriorhodopsin which shows a photocycle in the visible region of the optical spectrum. The scanning system, in response to routing information, traces a routing path(s) between an input(s) and a selected output(s) which alters the index of refraction in the path(s) traced in the photorefractive material. An optical input signal then propagates along the traced path between the selected input(s) and the selected output(s).

Adaptive optical waveguides

Adaptive optical waveguide router

An electronic phase shifter splits an input signal into two signals whose amplitudes are set by a weighting circuit controlled by a phase shift control signal. Each of the two outputs of the weighting circuit is loaded with an RLC resonator, one tuned to a frequency lower than that of the input signal and one tuned to a frequency higher than that of the input signal. The loaded outputs are recombined in a vector summing network to synthesize the required phase shifted output signal. This technique permits implementation on a monolithic integrated circuit (MIC) with high gain at high frequencies (e.g. 10 GHz). It also allows a large dynamic range of operation and a large (i.e., greater than 90 degrees) controllable phase shift. This is accomplished without the use of variable reactance elements or any other components external to the MIC.

Growing community of inventors

Carp, Canada

Steven P McGarry