Patent ID: 6956998

Claim:
An optical wave-guiding device comprising 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, wherein at least said first and second waveguides and said reflective coupling region are formed as an integral part of a single chip, wherein said reflective coupling region is able to revert at least most of the radiation from the first waveguide to the second waveguide, wherein the device is structured to provide a desired optical delay of radiation propagating therethrough, and wherein the length of said reflective coupling region is selected such that most of the radiation from the first waveguide is propagated towards the first side of the device via the second waveguide.