Patents by Inventor Ichiro Yoshino
Ichiro Yoshino 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).
-
Publication number: 20240414088Abstract: A first device transmits a first random number to a second device through a first quantum channel, and receives a second random number from the second device through a second quantum channel. The first device generates a first encryption key based on the first random number and the second random number. The second device transmits the second random number to the first device through the second quantum channel, and receives the first random number from the first device through the first quantum channel. The second device generates a second encryption key based on the first random number and the second random number.Type: ApplicationFiled: December 28, 2023Publication date: December 12, 2024Applicant: NEC CorporationInventors: Takao OCHI, Ken-ichiro YOSHINO, Akio TAJIMA
-
Publication number: 20240405977Abstract: An object is to prevent eavesdropping in quantum key distribution. A synchronization signal reception device receives a synchronization signal that is an optical signal for defining a timing at which a quantum signal is detected, and outputs a reference signal corresponding to the synchronization signal. A clock signal generation unit generates a clock signal in response to the reference signal. A photon detection device detects a photon of the quantum signal in response to the clock signal. A timing of the clock signal randomly changes within a predetermined range.Type: ApplicationFiled: January 24, 2022Publication date: December 5, 2024Applicants: NEC Corporation, National Institute of Information and Communications Technology, NATIONAL UNIVERSITY CORPORATION HOKKAIDO UNIVERSITY, The University of TokyoInventors: Ken-ichiro YOSHINO, Mikio FUJIWARA, Akihisa TOMITA, Masato KOASHI, Masahiro TAKEOKA
-
Patent number: 12124364Abstract: A synthetic judgment section performs synthetic judgment of randomness test for shared random numbers by combining a result of a first randomness test and a result of a second randomness test, the first randomness test being performed on the shared random numbers by a first communication device and the second randomness test being performed on the shared random numbers by a second communication device wherein a result of the synthetic judgment is safely notified to at least one of the first communication device and the second communication device, wherein the first randomness test and the second randomness test are different with respect to at least one of randomness test to be used and random number portion to be tested.Type: GrantFiled: October 19, 2018Date of Patent: October 22, 2024Assignee: NEC CORPORATIONInventors: Akio Tajima, Ken-ichiro Yoshino
-
Patent number: 12113578Abstract: An optical sender is disclosed, which alone makes it possible to reliably decide whether modulation timing is correct or incorrect and to adjust the modulation timing. The optical sender includes: a first modulator that outputs a first optical pulse train subjected to intensity modulation; an asymmetric interferometer that outputs a second optical pulse train of double pulses; a second modulator (104) that outputs a third optical pulse train subjected to send-data modulation for each pulse pair; nd an optical intensity measuring device that measures an optical intensity of the third optical pulse train, a controller, when changing either of a first optical pulse train according to intensity modulation pattern and a second optical pulse train according to send-data modulation pattern, decides whether the modulation timing is correct or incorrect, based on optical intensity of the third optical pulse train.Type: GrantFiled: June 10, 2020Date of Patent: October 8, 2024Assignee: NEC CORPORATIONInventor: Ken-ichiro Yoshino
-
Publication number: 20240313950Abstract: A terminal apparatus, a management apparatus, a communication system, a communication method, a management method, and a non-transitory computer readable medium capable of reliably acquiring a cryptographic key for quantum cryptographic communication are provided. A terminal apparatus (10) includes an acquisition unit (11) that acquires a cryptographic key from a management apparatus by designating communication source identification information and communication destination identification information for the management apparatus, and requesting the cryptographic key from the management apparatus, the management apparatus managing a cryptographic key distributed by using a QKD technology, and a communication unit (12) that performs cryptographic communication with another terminal apparatus by using the cryptographic key acquired by the acquisition unit (11).Type: ApplicationFiled: June 17, 2021Publication date: September 19, 2024Applicants: NEC Corporation, NEC Platforms, Ltd.Inventors: Ken TANAKA, Ken-ichiro YOSHINO, Tomoyasu IZUMIYA
-
Publication number: 20240129042Abstract: A communication device includes a nested modulator composed of sub modulators and a phase shifter. The nested modulator is controlled by: modulating a double pulse by phase and intensity modulation according to transmission information, wherein the double pulse thus modulated is transmitted to another communication device; controlling bias voltages applied respectively to the sub modulators so that a first error rate on the intensity modulation is minimized; and controlling a bias voltage applied to the phase shifter so that a second error rate on the phase modulation is minimized.Type: ApplicationFiled: October 10, 2023Publication date: April 18, 2024Applicant: NEC CorporationInventor: Ken-ichiro YOSHINO
-
Publication number: 20240089093Abstract: An object is to prevent eavesdropping in quantum key distribution. A decoding unit decodes a quantum signal incident thereinto. A plurality of detect photons of the decoded quantum signal output from the decoding unit. A signal processing unit detects bits of the decoded quantum signal based on photon detection results of the plurality of detectors. A control unit perform switching processing by switching destinations to which two decoded quantum signals corresponding to one encoding basis are output between the plurality of detectors, and switching the bits detected by the signal processing unit based on the respective photon detection results of the plurality of detectors.Type: ApplicationFiled: January 24, 2022Publication date: March 14, 2024Applicants: NEC CORPORATION, NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY, NATIONAL UNIVERSITY CORPORATION HOKKAIDO UNIVERSITY, THE UNIVERSITY OF TOKYOInventors: Ken-ichiro YOSHINO, Mikio FUJIWARA, Akihisa TOMITA, Masato KOASHI, Masahiro TAKEOKA, Masahide SASAKI
-
Publication number: 20240080184Abstract: An object is to prevent eavesdropping in quantum key distribution. A photon detector outputs an output current indicating a result of detecting a quantum signal. A current-voltage conversion unit converts the output current into an output voltage signal. An analog-to-digital converter outputs an output voltage signal obtained by analog-digital conversion of the output voltage signal. A signal processing unit performs predetermined signal processing on the output voltage signal, and outputs a photon detection signal indicating a result of detecting the quantum signal. When a time difference between a timing at which the quantum signal is incident into the photon detector and a reference timing determined based on a clock signal is not within a determination range, the photon detection signal is not output from the signal processing unit.Type: ApplicationFiled: January 24, 2022Publication date: March 7, 2024Applicants: NEC Corporation, National Institute of Information and Communications Technology, NATIONAL UNIVERSTIY CORPORATION HOKKAIDO UNIVERSTIY, The University of TokyoInventors: Ken-ichiro YOSHINO, Mikio FUJIWARA, Akihisa TOMITA, Masato KOASHI, Masahiro TAKEOKA, Masahide SASAKI
-
Patent number: 11909647Abstract: A first device transmits a first random number to a second device through a first quantum channel, and receives a second random number from the second device through a second quantum channel. The first device generates a first encryption key based on the first random number and the second random number. The second device transmits the second random number to the first device through the second quantum channel, and receives the first random number from the first device through the first quantum channel. The second device generates a second encryption key based on the first random number and the second random number.Type: GrantFiled: July 9, 2020Date of Patent: February 20, 2024Assignee: NEC CORPORATIONInventors: Takao Ochi, Ken-ichiro Yoshino, Akio Tajima
-
Patent number: 11733357Abstract: A 3-dimensional measuring device includes: a light source unit; a projection optical system; a scanning mirror that is provided to be rotatable about a rotating shaft in a state of being inclined with respect to a shaft center of the rotating shaft to radiate a range-finding light within a plane crossing the rotating shaft in a rotary manner; a light-receiving optical system that receives a reflection range-finding light; a reference light optical system that is provided in a range outside a measuring range within a radiation range to receive and reflect the range-finding light as an internal reference light, the reference light optical system being capable of changing a light quantity of the internal reference light; and a light receiving element that receives the reflection range-finding light and the internal reference light.Type: GrantFiled: October 28, 2022Date of Patent: August 22, 2023Assignee: TOPCON CORPORATIONInventors: Yasushi Tanaka, Takaaki Saito, Ken'ichiro Yoshino, Mitsuru Kanokogi
-
Publication number: 20230254045Abstract: An optical sender is disclosed, which alone makes it possible to reliably decide whether modulation timing is correct or incorrect and to adjust the modulation timing. The optical sender includes: a first modulator that outputs a first optical pulse train subjected to intensity modulation; an asymmetric interferometer that outputs a second optical pulse train of double pulses; a second modulator (104) that outputs a third optical pulse train subjected to send-data modulation for each pulse pair; nd an optical intensity measuring device that measures an optical intensity of the third optical pulse train, a controller, when changing either of a first optical pulse train according to intensity modulation pattern and a second optical pulse train according to send-data modulation pattern, decides whether the modulation timing is correct or incorrect, based on optical intensity of the third optical pulse train.Type: ApplicationFiled: June 10, 2020Publication date: August 10, 2023Applicant: NEC CorporationInventor: Ken-ichiro YOSHINO
-
Publication number: 20230077077Abstract: A 3-dimensional measuring device includes: a light source unit; a projection optical system; a scanning mirror that is provided to be rotatable about a rotating shaft in a state of being inclined with respect to a shaft center of the rotating shaft to radiate a range-finding light within a plane crossing the rotating shaft in a rotary manner; a light-receiving optical system that receives a reflection range-finding light; a reference light optical system that is provided in a range outside a measuring range within a radiation range to receive and reflect the range-finding light as an internal reference light, the reference light optical system being capable of changing a light quantity of the internal reference light; and a light receiving element that receives the reflection range-finding light and the internal reference light.Type: ApplicationFiled: October 28, 2022Publication date: March 9, 2023Applicant: TOPCON CORPORATIONInventors: Yasushi TANAKA, Takaaki SAITO, Ken'ichiro YOSHINO, Mitsuru KANOKOGI
-
Patent number: 11546065Abstract: An optical modulation method and device capable of stably generating an optical signal including a zero-intensity state among four states required for phase-time coding scheme by a nested modulator, is provided. A controller controls the phase difference generated by the phase shifter and an intensity and a magnitude of phase modulation provided by each of the first modulator and the second modulator to change an output lightwave of the nested modulator between four constellation points (S1-S4) on IQ plane. A first constellation point (S4) of the four constellation points has an intensity of 0, a second constellation point (S1) has a relative intensity of 1, each of a third constellation point (S2) and a fourth constellation point (S3) has a relative intensity ranging from 0 to 1, and the third and the fourth constellation points has a phase difference of 90 degrees.Type: GrantFiled: March 6, 2020Date of Patent: January 3, 2023Assignee: NEC CORPORATIONInventor: Ken-ichiro Yoshino
-
Patent number: 11536567Abstract: A surveying instrument comprises a light projecting optical system for projecting a distance measuring light to a predetermined measuring point, a light receiving optical system for receiving a reflected distance measuring light and an infrared light from the measuring point, and an arithmetic control module for controlling a distance measurement and a temperature measurement based on light receiving results of the reflected distance measuring light and the infrared light, and the arithmetic control module measures a distance to the measuring point based on light receiving results of the reflected distance measuring light received by a photodetector of the light receiving optical system, and measures a temperature of the measuring point based on light receiving results of the infrared light received by a temperature sensor of the light receiving optical system.Type: GrantFiled: September 6, 2018Date of Patent: December 27, 2022Assignee: TOPCON CorporationInventors: Taichi Yuasa, Ken-ichiro Yoshino
-
Patent number: 11520015Abstract: A 3-dimensional measuring device includes: a light source unit; a projection optical system; a scanning mirror that is provided to be rotatable about a rotating shaft in a state of being inclined with respect to a shaft center of the rotating shaft to radiate a range-finding light within a plane crossing the rotating shaft in a rotary manner; a light-receiving optical system that receives a reflection range-finding light; a reference light optical system that is provided in a range outside a measuring range within a radiation range to receive and reflect the range-finding light as an internal reference light, the reference light optical system being capable of changing a light quantity of the internal reference light; and a light receiving element that receives the reflection range-finding light and the internal reference light.Type: GrantFiled: August 21, 2018Date of Patent: December 6, 2022Assignee: TOPCON CORPORATIONInventors: Yasushi Tanaka, Takaaki Saito, Ken'ichiro Yoshino, Mitsuru Kanokogi
-
Patent number: 11502831Abstract: A quantum key distribution device is provided with an encoding unit which encodes an optical pulse train; an intensity modulating unit which subjects the encoded optical pulse train to N (where N is an integer at least equal to 3) types of intensity modulation having mutually different intensities, with different timings; and a first key distillation processing unit which generates an encryption key on the basis of a data sequence obtained by removing data obtained from an optical pulse having a specific modulation pattern from a data sequence used by the encoding unit and the intensity modulating unit.Type: GrantFiled: August 31, 2017Date of Patent: November 15, 2022Assignees: NEC CORPORATION, NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY, National University Corporation Hokkaido UniversityInventors: Ken-ichiro Yoshino, Mikio Fujiwara, Masahide Sasaki, Akihisa Tomita
-
Patent number: 11435457Abstract: A surveying instrument comprises a projection optical system for irradiating a distance measuring light which is a linearly-polarized light to an object to be measured, a light receiving optical system for receiving a reflected distance measuring light from the object to be measured, a polarization selecting module for selecting a polarization of the reflected distance measuring light received by the light receiving optical system and an arithmetic control module for controlling a distance measurement based on a light receiving result of the reflected distance measuring light, wherein the arithmetic control module is configured to give a material information to a distance measurement result of the object to be measured based on a change in light receiving amounts caused due to a selection of the polarization by the polarization selecting module.Type: GrantFiled: July 29, 2019Date of Patent: September 6, 2022Assignee: TOPCON CorporationInventors: Ken-ichiro Yoshino, Taizo Eno, Hideki Morita, Kohei Fujita
-
Patent number: 11402506Abstract: A laser measuring instrument comprises a light emitter, a driver, a scanning unit, a light receiving signal processing module for detecting a reciprocating time per pulsed light of a distance measuring light and performing a distance measurement, and a timing generating circuit for issuing a timing signal, wherein the timing generating circuit is configured to issue a timing signal for making the light emitter pulse-emit in a short cycle and a timing signal for pausing a light emission, the driver is configured to make the light emitter pulse-emit according to the timing signals, a light emission time interval in the short cycle is set such that a measuring point is multiply irradiated with the pulsed light by two or more times within a time when the pulsed light passes the measuring point, and the light receiving signal processing module is configured to integrate acquired light receiving signals and to carry out the distance measurement.Type: GrantFiled: September 17, 2018Date of Patent: August 2, 2022Assignee: TOPCON CorporationInventors: Fumio Ohtomo, Kaoru Kumagai, Ken-ichiro Yoshino
-
Publication number: 20220182151Abstract: An optical modulation method and device capable of stably generating an optical signal including a zero-intensity state among four states required for phase-time coding scheme by a nested modulator, is provided. A controller controls the phase difference generated by the phase shifter and an intensity and a magnitude of phase modulation provided by each of the first modulator and the second modulator to change an output lightwave of the nested modulator between four constellation points (S1-S4) on IQ plane. A first constellation point (S4) of the four constellation points has an intensity of 0, a second constellation point (S1) has a relative intensity of 1, each of a third constellation point (S2) and a fourth constellation point (S3) has a relative intensity ranging from 0 to 1, and the third and the fourth constellation points has a phase difference of 90 degrees.Type: ApplicationFiled: March 6, 2020Publication date: June 9, 2022Applicant: NEC CorporationInventor: Ken-ichiro YOSHINO
-
Patent number: 11271661Abstract: [Problem] A method, a device, a system and a program that can adjust the drive timing of a photon detector with high speed and high reliability is provided.Type: GrantFiled: March 19, 2018Date of Patent: March 8, 2022Assignee: NEC CORPORATIONInventor: Ken-ichiro Yoshino