Patents by Inventor Noriko Sasada
Noriko Sasada 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: 11563302Abstract: A ridge type semiconductor optical device includes a first conductivity type semiconductor layer including at least a first stripe section; an active layer including at least an active stripe section on the first stripe section; a second conductivity type semiconductor layer including at least a second stripe section on the active stripe section; a ridge electrode on the second stripe section; an insulation film on an end face of each of the first stripe section, the active stripe section, and the second stripe section; and a film heater on the insulation film, the film heater overlapping with the end face of at least the first stripe section.Type: GrantFiled: December 2, 2020Date of Patent: January 24, 2023Assignee: Lumentum Japan, Inc.Inventors: Akira Nakanishi, Noriko Sasada, Takayuki Nakajima, Yuji Sekino
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Publication number: 20210376565Abstract: A ridge type semiconductor optical device includes a first conductivity type semiconductor layer including at least a first stripe section; an active layer including at least an active stripe section on the first stripe section; a second conductivity type semiconductor layer including at least a second stripe section on the active stripe section; a ridge electrode on the second stripe section; an insulation film on an end face of each of the first stripe section, the active stripe section, and the second stripe section; and a film heater on the insulation film, the film heater overlapping with the end face of at least the first stripe section.Type: ApplicationFiled: December 2, 2020Publication date: December 2, 2021Inventors: Akira NAKANISHI, Noriko SASADA, Takayuki NAKAJIMA, Yuji SEKINO
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Patent number: 10771161Abstract: Provided is an optical transmission module which can generate PAM4 optical modulation signals without converting a plurality of binary electric signals to a multi-level electric signal. An optical transmission module (200) comprising: a light source (60) for emitting continuous waveform (CW) light; optical modulators (51,52,53) arranged in series with a path of the CW light configured to modulate the CW light by switching relatively large absorption and relatively small absorption of the optical modulators in response to a modulation signal applied to the respective optical modulators; and an arithmetic logic circuit (100) configured to receive a plurality of binary electrical signals, and then to perform logic operation on the plurality of binary electrical signals for generating a new plurality of binary electrical signals, wherein each of the new plurality of binary electrical signals is applied to the respective optical modulators as the modulation signal.Type: GrantFiled: December 7, 2017Date of Patent: September 8, 2020Assignee: Lumentum Japan, Inc.Inventors: Atsushi Nakamura, Shunya Yamauchi, Yoriyoshi Yamaguchi, Nozomu Yasuhara, Yoshihiro Nakai, Hideaki Asakura, Noriko Sasada, Takayoshi Fukui, Hiroki Irie
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Patent number: 10700489Abstract: Provided is an optical semiconductor device including a semiconductor substrate; a first semiconductor multilayer that is stacked on a first surface side of the semiconductor substrate, has a mesa structure extending along a light emitting direction, and emits light from an exit end surface; an electrode pad portion for wire bonding which is electrically connected to the upper surface of the mesa structure of the first semiconductor multilayer, is disposed on one side of the mesa structure, and is electrically connected to outside; and an electrode pad peripheral portion including a first rising surface which is in contact with the outer edge of the electrode pad portion on the exit end surface side and rises along the stacking direction from the electrode pad portion, in which a lower surface of the electrode pad portion is higher than the upper surface of the mesa structure of the first semiconductor multilayer.Type: GrantFiled: March 26, 2018Date of Patent: June 30, 2020Assignee: Lumentum Japan, Inc.Inventors: Akira Nakanishi, Noriko Sasada, Takayuki Nakajima
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Publication number: 20190028204Abstract: Provided is an optical transmission module which can generate PAM4 optical modulation signals without converting a plurality of binary electric signals to a multi-level electric signal. An optical transmission module (200) comprising: a light source (60) for emitting continuous waveform (CW) light; optical modulators (51,52,53) arranged in series with a path of the CW light configured to modulate the CW light by switching relatively large absorption and relatively small absorption of the optical modulators in response to a modulation signal applied to the respective optical modulators; and an arithmetic logic circuit (100) configured to receive a plurality of binary electrical signals, and then to perform logic operation on the plurality of binary electrical signals for generating a new plurality of binary electrical signals, wherein each of the new plurality of binary electrical signals is applied to the respective optical modulators as the modulation signal.Type: ApplicationFiled: December 7, 2017Publication date: January 24, 2019Inventors: Atsushi NAKAMURA, Shunya YAMAUCHI, Yoriyoshi YAMAGUCHI, Nozomu YASUHARA, Yoshihiro NAKAI, Hideaki ASAKURA, Noriko SASADA, Takayoshi FUKUI, Hiroki IRIE
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Publication number: 20180287339Abstract: Provided is an optical semiconductor device including a semiconductor substrate; a first semiconductor multilayer that is stacked on a first surface side of the semiconductor substrate, has a mesa structure extending along a light emitting direction, and emits light from an exit end surface; an electrode pad portion for wire bonding which is electrically connected to the upper surface of the mesa structure of the first semiconductor multilayer, is disposed on one side of the mesa structure, and is electrically connected to outside; and an electrode pad peripheral portion including a first rising surface which is in contact with the outer edge of the electrode pad portion on the exit end surface side and rises along the stacking direction from the electrode pad portion, in which a lower surface of the electrode pad portion is higher than the upper surface of the mesa structure of the first semiconductor multilayer.Type: ApplicationFiled: March 26, 2018Publication date: October 4, 2018Inventors: Akira NAKANISHI, Noriko SASADA, Takayuki NAKAJIMA
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Patent number: 9806821Abstract: Multilevel optical intensity modulation high in accuracy is performed using electro-absorption optical modulators. There is provided a plurality of EA modulators connected in series in a path of an optical signal from a light source, and a multilevel-coded modulated optical signal is generated by modulating an intensity of an input optical signal from the light source based on a modulation signal using the EA modulators. Each of the EA modulators is switched between an ON state and an OFF state of optical absorption in accordance with the modulation signal. Regarding an extinction ratio of the ON state to the OFF state in each of the EA modulators, the EA modulators have respective values difference from each other, and are arranged in ascending order of the extinction ratio from the light source side.Type: GrantFiled: June 1, 2016Date of Patent: October 31, 2017Assignee: OCLARO JAPAN, INC.Inventors: Atsushi Nakamura, Shunya Yamauchi, Yoriyoshi Yamaguchi, Noriko Sasada, Nozomu Yasuhara, Takayoshi Fukui, Hiroki Irie
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Patent number: 9726914Abstract: Preferable simultaneous achievement of the target characteristics with respect to both of the modulation bandwidth and the extinction ratio in the optical intensity modulation using the electro-absorption optical modulator is realized with a simple circuit configuration. The modulator integrated semiconductor laser element includes a plurality of EA modulators disposed in series in an optical signal path, and each adapted to absorb light in accordance with an applied voltage. The modulator driver for supplying the EA modulator with the applied voltage is provided for each of the EA modulators. The plurality of modulator drivers generates the applied voltage common to the plurality of EA modulators in accordance with a control signal. The modulator lengths of the plurality of EA modulators are set so that the closer to the light source the EA modulator is, the shorter the modulator length is.Type: GrantFiled: June 6, 2016Date of Patent: August 8, 2017Assignee: OCLARO JAPAN, INC.Inventors: Atsushi Nakamura, Shunya Yamauchi, Noriko Sasada, Takayoshi Fukui, Nozomu Yasuhara
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Publication number: 20160370609Abstract: Preferable simultaneous achievement of the target characteristics with respect to both of the modulation bandwidth and the extinction ratio in the optical intensity modulation using the electro-absorption optical modulator is realized with a simple circuit configuration. The modulator integrated semiconductor laser element includes a plurality of EA modulators disposed in series in an optical signal path, and each adapted to absorb light in accordance with an applied voltage. The modulator driver for supplying the EA modulator with the applied voltage is provided for each of the EA modulators. The plurality of modulator drivers generates the applied voltage common to the plurality of EA modulators in accordance with a control signal. The modulator lengths of the plurality of EA modulators are set so that the closer to the light source the EA modulator is, the shorter the modulator length is.Type: ApplicationFiled: June 6, 2016Publication date: December 22, 2016Inventors: Atsushi NAKAMURA, Shunya YAMAUCHI, Noriko SASADA, Takayoshi FUKUI, Nozomu YASUHARA
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Publication number: 20160365929Abstract: Multilevel optical intensity modulation high in accuracy is performed using electro-absorption optical modulators. There is provided a plurality of EA modulators connected in series in a path of an optical signal from a light source, and a multilevel-coded modulated optical signal is generated by modulating an intensity of an input optical signal from the light source based on a modulation signal using the EA modulators. Each of the EA modulators is switched between an ON state and an OFF state of optical absorption in accordance with the modulation signal. Regarding an extinction ratio of the ON state to the OFF state in each of the EA modulators, the EA modulators have respective values difference from each other, and are arranged in ascending order of the extinction ratio from the light source side.Type: ApplicationFiled: June 1, 2016Publication date: December 15, 2016Inventors: Atsushi NAKAMURA, Shunya YAMAUCHI, Yoriyoshi YAMAGUCHI, Noriko SASADA, Nozomu YASUHARA, Takayoshi FUKUI, Hiroki IRIE
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Patent number: 7733929Abstract: A wavelength tunable laser module for DWDM is used, in which a single electroabsorption modulator integrated laser is mounted and an oscillation wavelength is made tunable by temperature control. Driving conditions of a laser and a modulator are determined such that they have approximately the same modulation and transmission characteristics in a temperature control range. Such an electroabsorption modulator integrated laser is used and the driving conditions are incorporated, thereby a small, inexpensive wavelength tunable optical transmitter can be provided.Type: GrantFiled: June 14, 2006Date of Patent: June 8, 2010Assignee: Opnext Japan, Inc.Inventors: Noriko Sasada, Kazuhiko Naoe, Kazuhise Uomi, Masanobu Okayasu
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Patent number: 7605402Abstract: A chip carrier includes a metal-coated portion formed on a front surface of a substrate and to be mounted a device, and a rear surface of the substrate being coated with a metal, in which a metal-coated portion is formed on a side surface of the substrate and the metal-coated portion on the front surface of substrate is connected with the metal-coated portion on the rear surface by the metal-coated portion formed on the side surface of the substrate, thereby maintaining frequency characteristics of the optical semiconductor device.Type: GrantFiled: November 18, 2005Date of Patent: October 20, 2009Assignee: OpNext Japan, Inc.Inventors: Noriko Sasada, Kazuhiko Naoe, Masataka Shirai, Hideo Arimoto, Satoshi Tada
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Patent number: 7593445Abstract: A semiconductor optical device has a semiconductor laser portion and a modulator portion which have different mesa structures. The mesa structure of the semiconductor laser portion is a ridge waveguide structure which has air around the mesa. The mesa structure of the modulator portion is a planarized ridge waveguide structure which has an organic insulator buried around the mesa.Type: GrantFiled: January 29, 2007Date of Patent: September 22, 2009Assignee: Opnext Japan, Inc.Inventors: Noriko Sasada, Kazuhiko Naoe
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Publication number: 20070297475Abstract: A semiconductor optical device has a semiconductor laser portion and a modulator portion which have different mesa structures. The mesa structure of the semiconductor laser portion is a ridge waveguide structure which has air around the mesa. The mesa structure of the modulator portion is a planarized ridge waveguide structure which has an organic insulator buried around the mesa.Type: ApplicationFiled: January 29, 2007Publication date: December 27, 2007Inventors: Noriko Sasada, Kazuhiko Naoe
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Publication number: 20070081565Abstract: A wavelength tunable laser module for DWDM is used, in which a single electroabsorption modulator integrated laser is mounted and an oscillation wavelength is made tunable by temperature control. Driving conditions of a laser and a modulator are determined such that they have approximately the same modulation and transmission characteristics in a temperature control range. Such an electroabsorption modulator integrated laser is used and the driving conditions are incorporated, thereby a small, inexpensive wavelength tunable optical transmitter can be provided.Type: ApplicationFiled: June 14, 2006Publication date: April 12, 2007Inventors: Noriko Sasada, Kazuhiko Naoe, Kazuhise Uomi, Masanobu Okayasu
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Patent number: 7130100Abstract: Even for a driving impedance of 25 ?, high transmission waveform quality of an optical transmission module is maintained using an optical modulator element designed for a driving impedance of 50 ?. The above can be achieved by adopting an optical module 100 that includes an input electrode for electrical signals, an optical modulator element for modulating laser light using the electrical signals, a termination resistance element, a first bonding wire for connecting the input electrode and the optical modulator element, a second bonding wire for connecting the optical modulator element and the termination resistance element, and a third bonding wire for connecting the input electrode and the termination resistance element.Type: GrantFiled: May 18, 2005Date of Patent: October 31, 2006Assignee: Opnext Japan, Inc.Inventors: Osamu Kagaya, Noriko Sasada, Kazuhiko Naoe
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Patent number: 7030418Abstract: A chip carrier includes a metal-coated portion formed on a front surface of a substrate and to be mounted a device, and a rear surface of the substrate being coated with a metal, in which a metal-coated portion is formed on a side surface of the substrate and the metal-coated portion on the front surface of substrate is connected with the metal-coated portion on the rear surface by the metal-coated portion formed on the side surface of the substrate, thereby maintaining frequency characteristics of the optical semiconductor device.Type: GrantFiled: March 25, 2004Date of Patent: April 18, 2006Assignee: OpNext Japan, Inc.Inventors: Noriko Sasada, Kazuhiko Naoe, Masataka Shirai, Hideo Arimoto, Satoshi Tada
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Publication number: 20060076573Abstract: A chip carrier includes a metal-coated portion formed on a front surface of a substrate and to be mounted a device, and a rear surface of the substrate being coated with a metal, in which a metal-coated portion is formed on a side surface of the substrate and the metal-coated portion on the front surface of substrate is connected with the metal-coated portion on the rear surface by the metal-coated portion formed on the side surface of the substrate, thereby maintaining frequency characteristics of the optical semiconductor device.Type: ApplicationFiled: November 18, 2005Publication date: April 13, 2006Inventors: Noriko Sasada, Kazuhiko Naoe, Masataka Shirai, Hideo Arimoto, Satoshi Tada
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Publication number: 20060007516Abstract: Even for a driving impedance of 25 ?, high transmission waveform quality of an optical transmission module is maintained using an optical modulator element designed for a driving impedance of 50 ?. The above can be achieved by adopting an optical module 100 that includes an input electrode for electrical signals, an optical modulator element for modulating laser light using the electrical signals, a termination resistance element, a first bonding wire for connecting the input electrode and the optical modulator element, a second bonding wire for connecting the optical modulator element and the termination resistance element, and a third bonding wire for connecting the input electrode and the termination resistance element.Type: ApplicationFiled: May 18, 2005Publication date: January 12, 2006Inventors: Osamu Kagaya, Noriko Sasada, Kazuhiko Naoe
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Publication number: 20050139843Abstract: A chip carrier includes a metal-coated portion formed on a front surface of a substrate and to be mounted a device, and a rear surface of the substrate being coated with a metal, in which a metal-coated portion is formed on a side surface of the substrate and the metal-coated portion on the front surface of substrate is connected with the metal-coated portion on the rear surface by the metal-coated portion formed on the side surface of the substrate, thereby maintaining frequency characteristics of the optical semiconductor device.Type: ApplicationFiled: March 25, 2004Publication date: June 30, 2005Inventors: Noriko Sasada, Kazuhiko Naoe, Masataka Shirai, Hideo Arimoto, Satoshi Tada