Abstract: An optical modulator. The optical modulator comprising: a micro-ring resonator; and a bus waveguide, including an input waveguide region, an output waveguide region, and a coupling waveguide region optically coupled to the micro-ring resonator and located between the input waveguide region and the output waveguide region. The micro-ring resonator includes a modulation region, the modulation region being formed of a silicon portion and a III-V semiconductor portion separated by a crystalline rare earth oxide dielectric layer.

Abstract: A method of generating multiple channels of optical pulses comprises: providing a continuous wave optical input having an optical power; dividing the optical power of the optical input into equal consecutive slices in the time domain; and allocating the consecutive slices sequentially to two or more optical outputs such that each output forms a channel of optical pulses of equal pulse repetition rate shifted in time relative to the or each other channel.

Abstract: An optical modulator. The optical modulator comprising: a micro-ring resonator; and a bus waveguide, including an input waveguide region, an output waveguide region, and a coupling waveguide region optically coupled to the micro-ring resonator and located between the input waveguide region and the output waveguide region. The micro-ring resonator includes a modulation region, the modulation region being formed of a silicon portion and a III-V semiconductor portion separated by a crystalline rare earth oxide dielectric layer.

Abstract: An optical modulation system comprises a signal source configured to generate an amplitude modulated electrical signal having a bandwidth and divided into frequency components comprising at least a first frequency component covering a first portion of the bandwidth and a second frequency component covering a second portion of the bandwidth; and an electro-optic modulator for receiving an input optical signal, the modulator having a first optical path and a second optical path, the input optical signal being divided between the first optical path and the second optical path and recombined after propagation along the first optical path and the second optical path to produce an output optical signal, and at least one of the first optical path and the second optical path comprising a phase shifter comprising a pair of electrodes in which each electrode is configured to receive a driving signal; wherein the or each phase shifter is coupled to the signal source to receive at least one of said frequency components a

Abstract: An optical modulation system comprises a signal source configured to generate an amplitude modulated electrical signal having a bandwidth and divided into frequency components comprising at least a first frequency component covering a first portion of the bandwidth and a second frequency component covering a second portion of the bandwidth; and an electro-optic modulator for receiving an input optical signal, the modulator having a first optical path and a second optical path, the input optical signal being divided between the first optical path and the second optical path and recombined after propagation along the first optical path and the second optical path to produce an output optical signal, and at least one of the first optical path and the second optical path comprising a phase shifter comprising a pair of electrodes in which each electrode is configured to receive a driving signal; wherein the or each phase shifter is coupled to the signal source to receive at least one of said frequency components a

Abstract: The disclosure provides a method of forming an erasable optical coupler in a photonic device comprising a conventional optical waveguide formed in a crystalline wafer. The method comprises selectively implanting ions in a localized region of the wafer material adjacent to the conventional waveguide of the photonic device, to cause modification of the crystal lattice structure of, and a change in refractive index in, the ion implanted region of the wafer material to thereby form an ion implanted waveguide optically coupled to the adjacent conventional waveguide to couple light out therefrom, or in thereto. The crystalline wafer material and ion implanted waveguide are such that the crystal lattice structure or composition can be modified to adjust or remove the optical coupling with the conventional waveguide by further modification of the refractive index in the ion implanted region.

Abstract: A discrete wavelength tunable laser capable of switching between a plurality of lasing channels of different wavelengths, the tunable laser comprising: a semiconductor optical amplifier (SOA); a wavelength demultiplexer (Demux), having a Demux input which receives the output from the SOA, and a plurality of Demux outputs, each Demux output defining a different spatial path for a respective lasing channel; each of the respective lasing channels being within the bandwidth of the SOA; a reflector located within each spatial path for reflecting light of the respective lasing channel; and a lasing suppression mechanism located within each lasing channel; wherein one or more desired lasing channels are selected by application of the lasing suppression mechanism in each spatial path other than the one or more spatial paths corresponding to the one or more desired lasing channels.

Abstract: A method of operating an optical modulator. The optical modulator having: a rib waveguide which includes a junction which is either a PIN or PN junction, the junction having a breakdown voltage. The method comprising: applying a reverse bias to the junction, so as to operate the optical modulator around the breakdown voltage of the junction; operating the modulator in an avalanche multiplication and/or band-to-band tunnelling mode by increasing the reverse bias past the breakdown voltage.

Abstract: A method of trimming the refractive index of material forming at least part of one or more structures integrated in one or more pre-fabricated devices, the method comprising: implanting one or more first regions of material of one or more pre-fabricated devices, encompassing at least partially one or more device structures, with ions to alter the crystal form of the material within the one or more first regions and change the refractive index of the material within the one or more first regions; and heat treating one or more second regions of material of the one or more devices, encompassing at least partially the one or more first regions, to alter the crystal form of the material within the one or more first regions encompassed by the one or more second regions and change the refractive index thereof, thereby trimming the refractive index of the material of at least part of the one or more device structures, such that the one or more device structures provide one or more predetermined device outputs.

Abstract: A method of operating an optical modulator. The optical modulator having: a rib waveguide which includes a junction which is either a PIN or PN junction, the junction having a breakdown voltage. The method comprising: applying a reverse bias to the junction, so as to operate the optical modulator around the breakdown voltage of the junction; operating the modulator in an avalanche multiplication and/or band-to-band tunnelling mode by increasing the reverse bias past the breakdown voltage.

Abstract: The disclosure provides a method of forming an erasable optical coupler in a photonic device comprising a conventional optical waveguide formed in a crystalline wafer. The method comprises selectively implanting ions in a localized region of the wafer material adjacent to the conventional waveguide of the photonic device, to cause modification of the crystal lattice structure of, and a change in refractive index in, the ion implanted region of the wafer material to thereby form an ion implanted waveguide optically coupled to the adjacent conventional waveguide to couple light out therefrom, or in thereto. The crystalline wafer material and ion implanted waveguide are such that the crystal lattice structure or composition can be modified to adjust or remove the optical coupling with the conventional waveguide by further modification of the refractive index in the ion implanted region.

Abstract: A discrete wavelength tunable laser capable of switching between a plurality of lasing channels of different wavelengths, the tunable laser comprising: a semiconductor optical amplifier (SOA); a wavelength demultiplexer (Demux), having a Demux input which receives the output from the SOA, and a plurality of Demux outputs, each Demux output defining a different spatial path for a respective lasing channel; each of the respective lasing channels being within the bandwidth of the SOA; a reflector located within each spatial path for reflecting light of the respective lasing channel; and a lasing suppression mechanism located within each lasing channel; wherein one or more desired lasing channels are selected by application of the lasing suppression mechanism in each spatial path other than the one or more spatial paths corresponding to the one or more desired lasing channels.

Abstract: A method of trimming the refractive index of material forming at least part of one or more structures integrated in one or more pre-fabricated devices, the method comprising: implanting one or more first regions of material of one or more pre-fabricated devices, encompassing at least partially one or more device structures, with ions to alter the crystal form of the material within the one or more first regions and change the refractive index of the material within the one or more first regions; and heat treating one or more second regions of material of the one or more devices, encompassing at least partially the one or more first regions, to alter the crystal form of the material within the one or more first regions encompassed by the one or more second regions and change the refractive index thereof, thereby trimming the refractive index of the material of at least part of the one or more device structures, such that the one or more device structures provide one or more predetermined device outputs.

Abstract: Apparatus comprising at least one optical device (106) optically coupled to at least one waveguide (111) on an optical chip (100), characterized in that: (i) the optical device (106) is optically aligned with the waveguide (111) by aligning means (114, 116); (ii) the aligning means (114, 116) comprises at least one male member (114) and at least one female (116) member which locate together; (iii) one of the male member (114) and the female member (116) is positioned on the optical chip (100); (iv) the other one of the male member (114) and the female member (116) is positioned on a capping chip (102); and (v) the apparatus includes a mirror (108) for reflecting light from the optical device (106) to the waveguide (111).

Abstract: Apparatus comprising at least one optical device (106) optically coupled to at least one waveguide (111) on an optical chip (100), characterised in that: (i) the optical device (106) is optically aligned with the waveguide (111) by aligning means (114, 116); (ii) the aligning means (114, 116) comprises at least one male member (114) and at least one female (116) member which locate together; (iii) one of the male member (114) and the female member (116) is positioned on the optical chip (100); (iv) the other one of the male member (114) and the female member (116) is positioned on a capping chip (102); and (v) the apparatus includes a mirror (108) for reflecting light from the optical device (106) to the waveguide (111).

Abstract: A support adaptor assembly for a bearing press comprising a rectangular shaped header plate (1), a pair of adjustable support rods (4) each with an adaptor (9) on one end for providing a means of supporting an object (50) to be worked on with a bearing press either above or below the support members of the bearing press.

Abstract: A vehicle comprises a structure 10 including an elongate section 11 connected to chassis sections 12,13 at its ends. Each chassis section 12,13 carries two steerable drive wheels 18,20. Two engines 16 are provided, one carried by each chassis section 12, 13 to drive the wheels 18,20 of that chassis section 12,13. The vehicle can be driven transverse to or longitudinally of the elongate section 11. The elongate section 11 is offset in relation to the chassis sections 12,13. Each wheel 18,20 is mounted by an arm 22, each arm 22, being connected to each respective wheel 18,20 within the height of the wheel and at each side of the vehicle. On each chassis section 12,13 one arm 22 is connected to one side of its respective wheel 18,20 and the other arm 22 is connected to the other side of its respective wheel 18, 20. Each arm 22 is connected to two pivot points within the wheel 18,20 on the upright diametrical axis of the wheel.