Abstract: An all-optical bistable device, comprising: a splitting device having first and second inputs and first and second outputs, for receiving first light beam at the first input and directing the first beam as second and third beams propagating through respective first and second outputs; first optical path between the first output and the second input and second optical path between the second output and the second input for creating combined optical path for the first and second beams at the second input; the combined optical path includes a saturable optical amplifier for enhancing and diminishing one of the second and the third beams for driving the optical amplifier into a saturation state to create one of two stable states in which one of the second and the third beams is an enhanced beam and the other beam is a diminishing beam; at least one tapping device for tapping output signal from one of the first and the second optical paths, and at least one coupling device for coupling input signal into one of the

Abstract: In one version, the present invention provides an optical switching device including a splitting device having a first terminal for receiving an input signal and second and third terminals, and an optical loop associated with the second and third terminals and having first and second non-linear elements and first and second directing devices. One of the first and second non-linear elements may receive an activating signal from a third directing device and, in response to the activating signal, cause the optical loop to producing first and second output signals at the first and second directing devices, respectively. In another version, the present invention provides an optical gating device. The present invention also provides an optical switching device that may include two optical gating devices and an optical toggle device.

Abstract: An all-optical switch includes a field combiner to produce a first intermediate signal by combining electric fields of an optical information signal and an optical control signal; a fist power combiner to produce a second intermediate signal by combining powers of the optical information signal and the optical control signal; and a second power combiner to produce an optical output signal based on a power difference between the first and second intermediate signals.

Abstract: An optical AND logic gate includes a summing gate having first and second inputs for receiving first and second optical signals, and a threshold device. The gate produces an output corresponding to the AND product of the first and second optical signals. In another version the AND gate includes first and second inputs for receiving first and second optical signals, and an optical loop for producing an output corresponding to the AND product of the first and second optical signals. In an alternative versions a NAND gate is provided by applying an optical logic NOT on an AND gate.

Abstract: The present invention provides an optical delay, for example, an optical delay line, having at least first and second waveguides, each waveguide having a first end at a first side of the device and a second end at a second side of the device, wherein the second end of the first waveguide is coupled to the second end of the second waveguide at a reflective coupling region, which reverts the direction of propagation of radiation in the device from propagating towards the second side of the device via the first waveguide to propagating towards the first side of the device via the second waveguide.

Abstract: An optical threshold device including an input, an output, first and second radiation guiding branches, each branch having first and second terminals, at least one of the first and second branches having a non-linear optical element, first and second optical couplers, at least one of the first and second optical couplers having an asymmetric optical coupler, the first optical coupler configured to split an input signal of radiation from the input into a first radiation portion propagating through the first branch and a second radiation portion propagating through the second branch, the second optical coupler configured to combine the first and second radiation portions from the second terminals of the first and second branches, respectively, into an output signal at the output, wherein the non-linear optical element produces a phase shift between the first and second radiation portions and wherein the first and second radiation portions interfere at the second coupler in response to the phase shift.

Abstract: An optical threshold device including an optical loop having first and second terminals aid including at least one non-linear optical element and at least one optical attenuator; and an optical coupler able to couple a first portion of an input signal to the first terminal and a second portion of the input signal to the second terminal, wherein the optical loop is able to produce a first return signal at the second terminal and a second return signal at the first terminal, and wherein the optical coupler is able to combine the first and second return signals into an output signal.