Patents by Inventor Andrew John Ward
Andrew John Ward has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11630370Abstract: An optical transmitter comprises a directly coupled MZ interferometer and driver circuit. The MZ interferometer comprises a pair of differentially driven MZ electrodes configured to impart RF signals to light travelling through respective arms of the interferometer, and to receive DC bias as a positive voltage via lower n-type cladding of the MZ interferometer. The lower n-type cladding is at a different positive DC potential to an upper plane RF ground of the MZ interferometer, but the lower n-type cladding and the upper plane RF ground have similar AC potential. The MZ interferometer also comprises a pair of resistors in series configured to provide differential RF termination of the MZ electrodes; and a capacitive coupling between a virtual ground formed at a centre point between the pair of resistors and an RF ground configured to provide common-mode RF termination. The DC supply for the driver circuit is applied to the centre point of the RF termination.Type: GrantFiled: May 3, 2021Date of Patent: April 18, 2023Assignee: Lumentum Technology UK LimitedInventors: Samuel Davies, Andrew John Ward
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Publication number: 20210255521Abstract: An optical transmitter comprises a directly coupled MZ interferometer and driver circuit. The MZ interferometer comprises a pair of differentially driven MZ electrodes configured to impart RF signals to light travelling through respective arms of the interferometer, and to receive DC bias as a positive voltage via lower n-type cladding of the MZ interferometer. The lower n-type cladding is at a different positive DC potential to an upper plane RF ground of the MZ interferometer, but the lower n-type cladding and the upper plane RF ground have similar AC potential. The MZ interferometer also comprises a pair of resistors in series configured to provide differential RF termination of the MZ electrodes; and a capacitive coupling between a virtual ground formed at a centre point between the pair of resistors and an RF ground configured to provide common-mode RF termination. The DC supply for the driver circuit is applied to the centre point of the RF termination.Type: ApplicationFiled: May 3, 2021Publication date: August 19, 2021Inventors: Samuel DAVIES, Andrew John WARD
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Patent number: 11009659Abstract: The invention relates to optical modulation devices and, in particular, monolithically integrated optical modulation devices. Disclosed herein is a monolithically integrated optical modulation device (200) that comprises: an input optical port (210); an output optical port (215); and an optical waveguide for guiding light from the input optical port to the output optical port. A portion of the optical waveguide is split into at least two branches. The waveguide is configured to cause a net 180° change in direction of the light while guiding said light from the input optical port to the output optical port such that the input optical port and the output optical port are positioned on a first edge of the device. At least some of the net 180° change in direction is achieved within the branches of the waveguide.Type: GrantFiled: August 30, 2016Date of Patent: May 18, 2021Assignee: Lumentum Technology UK LimitedInventors: Andrew John Ward, Neil David Whitbread, Stephen Jones, Andrew Cannon Carter
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Patent number: 10996537Abstract: An optical transmitter comprises a directly coupled MZ interferometer and driver circuit. The MZ interferometer comprises a pair of differentially driven MZ electrodes configured to impart RF signals to light travelling through respective arms of the interferometer, and to receive DC bias as a positive voltage via lower n-type cladding of the MZ interferometer. The lower n-type cladding is at a different positive DC potential to an upper plane RF ground of the MZ interferometer, but the lower n-type cladding and the upper plane RF ground have similar AC potential. The MZ interferometer also comprises a pair of resistors in series configured to provide differential RF termination of the MZ electrodes; and a capacitive coupling between a virtual ground formed at a centre point between the pair of resistors and an RF ground configured to provide common-mode RF termination. The DC supply for the driver circuit is applied to the centre point of the RF termination.Type: GrantFiled: December 13, 2019Date of Patent: May 4, 2021Assignee: Lumentum Technology UK LimitedInventors: Samuel Davies, Andrew John Ward
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Patent number: 10784652Abstract: There is disclosed a DBR laser and a method of use. The DBR laser comprises a phase section in a cavity of the DBR laser and configured to adjust an optical path length of the cavity. A DBR section comprises a frequency tuning system configured to adjust a Bragg frequency of the DBR section. A detector is configured to detect laser light transmitted through the DBR section.Type: GrantFiled: September 27, 2017Date of Patent: September 22, 2020Assignee: Lumentum Technology UK LimitedInventors: Samuel Davies, Andrew John Ward, Andrew Cannon Carter
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Publication number: 20200201135Abstract: An optical transmitter comprises a directly coupled MZ interferometer and driver circuit. The MZ interferometer comprises a pair of differentially driven MZ electrodes configured to impart RF signals to light travelling through respective arms of the interferometer, and to receive DC bias as a positive voltage via lower n-type cladding of the MZ interferometer. The lower n-type cladding is at a different positive DC potential to an upper plane RF ground of the MZ interferometer, but the lower n-type cladding and the upper plane RF ground have similar AC potential. The MZ interferometer also comprises a pair of resistors in series configured to provide differential RF termination of the MZ electrodes; and a capacitive coupling between a virtual ground formed at a centre point between the pair of resistors and an RF ground configured to provide common-mode RF termination. The DC supply for the driver circuit is applied to the centre point of the RF termination.Type: ApplicationFiled: December 13, 2019Publication date: June 25, 2020Inventors: Samuel DAVIES, Andrew John WARD
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Publication number: 20190207366Abstract: There is disclosed a DBR laser and a method of use. The DBR laser comprises a phase section in a cavity of the DBR laser and configured to adjust an optical path length of the cavity. A DBR section comprises a frequency tuning system configured to adjust a Bragg frequency of the DBR section. A detector is configured to detect laser light transmitted through the DBR section.Type: ApplicationFiled: September 27, 2017Publication date: July 4, 2019Inventors: Samuel Davies, Andrew John Ward, Andrew Cannon Carter
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Publication number: 20180329269Abstract: The invention relates to optical modulation devices and, in particular, monolithically integrated optical modulation devices. Disclosed herein is a monolithically integrated optical modulation device (200) that comprises: an input optical port (210); an output optical port (215); and an optical waveguide for guiding light from the input optical port to the output optical port. A portion of the optical waveguide is split into at least two branches. The waveguide is configured to cause a net 180° change in direction of the light while guiding said light from the input optical port to the output optical port such that the input optical port and the output optical port are positioned on a first edge of the device. At least some of the net 180° change in direction is achieved within the branches of the waveguide.Type: ApplicationFiled: August 30, 2016Publication date: November 15, 2018Inventors: Andrew John Ward, Neil David Whitbread, Stephen Jones, Andrew Cannon Carter
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Patent number: 9209601Abstract: A monolithically integrated, tunable semiconductor laser with an optical waveguide, comprising a laser chip having epitaxial layers on a substrate and having first and second reflectors bounding an optical gain section and a passive section, wherein at least one of the reflectors is a distributed Bragg reflector section comprising a grating and configured to have a tunable reflection spectrum, wherein the laser is provided with a common earth electrode, wherein control electrodes are provided on the optical waveguide in at least the optical gain section and the at least one distributed Bragg reflector section, wherein the passive section is provided with an electrode or electrical tracking on the optical waveguide, the passive section is configured not to be drivable by an electrical control signal, and no grating is present within the passive section.Type: GrantFiled: September 8, 2014Date of Patent: December 8, 2015Assignee: OCLARO TECHNOLOGY LTDInventors: Sam Davies, Neil David Whitbread, Andrew John Ward, Robert Griffin
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Patent number: 9083144Abstract: An adjustable array includes a plurality of optical devices. Each adjustable array device has an optical light output therefrom and is configured whereby the corresponding optical lights of the plurality of optical devices have a predefined nonequivalent relationship relative to one another with respect to an output parameter. In response to a drive signal, the plurality of optical devices are further configured to adjust the corresponding optical lights with respect to the output parameter while substantially maintaining the predefined nonequivalent relationship.Type: GrantFiled: December 8, 2010Date of Patent: July 14, 2015Assignee: Oclaro Technology LimtedInventors: Giacinto Busico, David Williamson, Andrew Cannon Carter, Andrew John Ward, Lloyd Nicholas Langley
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Publication number: 20150010033Abstract: A monolithically integrated, tunable semiconductor laser with an optical waveguide, comprising a laser chip having epitaxial layers on a substrate and having first and second reflectors bounding an optical gain section and a passive section, wherein at least one of the reflectors is a distributed Bragg reflector section comprising a grating and configured to have a tunable reflection spectrum, wherein the laser is provided with a common earth electrode, wherein control electrodes are provided on the optical waveguide in at least the optical gain section and the at least one distributed Bragg reflector section, wherein the passive section is provided with an electrode or electrical tracking on the optical waveguide, the passive section is configured not to be drivable by an electrical control signal, and no grating is present within the passive section.Type: ApplicationFiled: September 8, 2014Publication date: January 8, 2015Inventors: Sam Davies, Neil David Whitbread, Andrew John Ward, Robert Griffin
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Patent number: 8749772Abstract: An optical wavelength monitor photodiode integrated on a wafer and/or an optical device and coupled to optical components thereof provides wavelength measurement. The optical wavelength monitor includes a photodiode configured to output a signal that is representative of a wavelength of the light. An additional photodiode may be included in the optical wavelength monitor, each photodiode differing from the other in operating characteristics. The monitor may be used in testing the optical device while in wafer form and when the optical device has been cleaved from the wafer at the bar level. Testing/monitoring of the optical device may also be performed during use, for example, to control the wavelength of a laser such as a tunable laser.Type: GrantFiled: July 2, 2010Date of Patent: June 10, 2014Assignee: Oclaro Technology LimitedInventors: Giacinto Busico, Neil David Whitbread, Andrew John Ward, Andrew Moseley
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Publication number: 20130250981Abstract: An adjustable array includes a plurality of optical devices. Each adjustable array device has an optical light output therefrom and is configured whereby the corresponding optical lights of the plurality of optical devices have a predefined nonequivalent relationship relative to one another with respect to an output parameter. In response to a drive signal, the plurality of optical devices are further configured to adjust the corresponding optical lights with respect to the output parameter while substantially maintaining the predefined nonequivalent relationship.Type: ApplicationFiled: December 8, 2010Publication date: September 26, 2013Applicant: OCLARO TECHNOLOGY LIMITEDInventors: Giacinto Busico, David Williamson, Andrew Cannon Carter, Andrew John Ward, Lloyd Nicholas Langley
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Patent number: 8457172Abstract: A Bragg grating has a local reflection strength which varies with position along the length of the grating so as to generate a non-uniform wavelength reflection spectrum, enabling compensation for a non-uniform gain profile of the gain section of a tunable laser. In another aspect, a Bragg comb grating is modulated by an envelope function which can also compensate for a non-uniform gain profile. The comb grating may be a phase change grating, with the envelope function shape being controlled by the length between phase changes and/or size of the phase changes.Type: GrantFiled: September 24, 2010Date of Patent: June 4, 2013Assignee: Oclaro Technology LimitedInventors: Douglas Charles John Reid, Andrew John Ward
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Patent number: 8295315Abstract: The present invention concerns tunable distributed Bragg reflector (DBR) semiconductor lasers, in particular a DBR laser with a branched optical waveguide 5 within which a plurality of differently shaped lasing cavities may be formed, and a method of operation of such a laser. The laser may comprise a phase control section (418), gain section (420, 422), a sampled grating DBR (412) giving a comb-line spectrum and two tunable, chirped DBRs (414, 416) for broadband frequency training and a coupling section (410).Type: GrantFiled: April 3, 2008Date of Patent: October 23, 2012Assignee: Oclaro Technology LimitedInventors: Andrew John Ward, Robert Walker, David James Robbins, Douglas Charles John Reid, Guy Towlson
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Publication number: 20120162648Abstract: An optical wavelength monitor photodiode integrated on a wafer and/or an optical device and coupled to optical components thereof provides wavelength measurement. The optical wavelength monitor includes a photodiode configured to output a signal that is representative of a wavelength of the light. An additional photodiode may be included in the optical wavelength monitor, each photodiode differing from the other in operating characteristics. The monitor may be used in testing the optical device while in wafer form and when the optical device has been cleaved from the wafer at the bar level. Testing/monitoring of the optical device may also be performed during use, for example, to control the wavelength of a laser such as a tunable laser.Type: ApplicationFiled: July 2, 2010Publication date: June 28, 2012Inventors: Giacinto Busico, Neil David Whitbread, Andrew John Ward, Andrew Moseley
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Patent number: 8160410Abstract: A Bragg reflector grating comprises a plurality of chirped grating sections (65-72), in which at least a first chirped grating section and a second chirped grating section have differing ranges of grating pitches. The combined range of grating pitches provided by the first and second chirped grating sections includes at least one discontinuity, such that the first and second chirped grating sections have one or more grating pitches in common and/or there are one or more ranges of grating pitches within the combined range of grating pitches that are absent.Type: GrantFiled: December 8, 2006Date of Patent: April 17, 2012Assignee: Oclaro Technology LimitedInventors: Douglas Charles John Reid, Andrew John Ward
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Publication number: 20110069727Abstract: A Bragg grating has a local reflection strength which varies with position along the length of the grating so as to generate a non-uniform wavelength reflection spectrum, enabling compensation for a non-uniform gain profile of the gain section of a tunable laser. In another aspect, a Bragg comb grating is modulated by an envelope function which can also compensate for a non-uniform gain profile. The comb grating may be a phase change grating, with the envelope function shape being controlled by the length between phase changes and/or size of the phase changes.Type: ApplicationFiled: September 24, 2010Publication date: March 24, 2011Applicant: Oclaro Technology LimitedInventors: Douglas Charles John REID, Andrew John Ward
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Patent number: 7830927Abstract: A tunable laser comprises a gain section and two or more reflectors. At least one of the reflectors is a Bragg grating comprising a reduced strength section comprising a base order periodic pattern of marks and spaces from at which at least some of the marks or spaces are missing. This enables the reflective strength of the grating to be controlled relative to the other reflector. The Bragg grating may be a phase change grating with individual sections being reduced in strength by line removal.Type: GrantFiled: September 26, 2006Date of Patent: November 9, 2010Assignee: Oclaro Technology LimitedInventors: Douglas Charles John Reid, Andrew John Ward
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Patent number: 7826508Abstract: A Bragg grating has a local reflection strength which varies with position along the length of the grating so as to generate a non-uniform wavelength reflection spectrum, enabling compensation for a non-uniform gain profile of the gain section of a tunable laser. In another aspect, a Bragg comb grating is modulated by an envelope function which can also compensate for a non-uniform gain profile. The comb grating may be a phase change grating, with the envelope function shape being controlled by the length between phase changes and/or size of the phase changes.Type: GrantFiled: September 22, 2006Date of Patent: November 2, 2010Assignee: Oclaro Technology LimitedInventors: Douglas Charles John Reid, Andrew John Ward