Patents by Inventor Takao Muramatsu
Takao Muramatsu 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: 10807516Abstract: A lighting circuit drives a light source including N (N represents an integer of 2 or more) multiple light-emitting elements coupled in series. A bypass switch circuit includes N multiple bypass switches, each coupled in parallel to a corresponding light-emitting element. A constant current driving circuit supplies a driving current stabilized to a target current to the light source. A light distribution controller controls the bypass switch circuit. For a given light distribution pattern, the duty ratio Di(%) is determined for each of the N multiple light-emitting elements. Multiple light-emitting elements are formed as control units having a sum total of duty ratios that is less than 100%. The light distribution controller controls the multiple bypass switches such that the multiple light-emitting elements included in the same control unit are not turned on at the same time.Type: GrantFiled: March 8, 2019Date of Patent: October 20, 2020Assignee: KOITO MANUFACTURING CO., LTD.Inventors: Yuta Maruyama, Kentarou Murakami, Takao Muramatsu
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Publication number: 20200195831Abstract: A left infrared camera module includes a left infrared irradiation unit configured to emit infrared toward a left side region of a vehicle, a left infrared camera configured to acquire infrared image data indicative of a surrounding environment in the left side region of the vehicle, and a control unit configured to control an operation of the left infrared irradiation unit. The control unit is configured to change an intensity of the infrared to be emitted from the left infrared irradiation unit, in correspondence to a condition relating to a traveling state of the vehicle. The left infrared camera module configured as described above can detect the surrounding environment in the side region of the vehicle without causing an uncomfortable feeling to other vehicle, a pedestrian and the like.Type: ApplicationFiled: December 13, 2019Publication date: June 18, 2020Applicant: KOITO MANUFACTURING CO., LTD.Inventors: Takao Muramatsu, Shigeyuki Watanabe, Masaaki Sato, Akinobu Kubota
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Patent number: 10676017Abstract: A vehicular lighting device includes a scanning light source. The scanning light source includes a semiconductor light source, and scans the output light of the semiconductor light source in a forward region ahead of the lighting device. A lighting circuit changes the light amount of the semiconductor light source in multiple levels in synchronization with the scanning of the scanning light source.Type: GrantFiled: October 15, 2017Date of Patent: June 9, 2020Assignee: KOITO MANUFACTURING CO., LTD.Inventors: Kentarou Murakami, Hitoshi Takeda, Takao Muramatsu
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Patent number: 10661701Abstract: A blade receives light emitted from a light source and repeats a predetermined periodic motion to scan the front of a vehicle with reflected light of the emitted light. A position detector generates a position detection signal S4 indicating a timing at which a predetermined reference point of the blade passes a predetermined position. Based on the position detection signal S4, a period calculator calculates a period Tp of the periodic motion of the blade. A light intensity calculator receives light-distribution-pattern information S3 to be formed in front of the vehicle and calculates light intensity to be generated by the light source at each time based on the position detection signal S4 and the period Tp. A driver turns on a semiconductor light source so as to obtain the light intensity calculated by the light intensity calculator at each time.Type: GrantFiled: June 22, 2017Date of Patent: May 26, 2020Assignee: KOITO MANUFACTURING CO., LTD.Inventors: Takeshi Toda, Kentarou Murakami, Masayasu Ito, Takao Muramatsu, Hidetada Tanaka, Satoshi Yamamura
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Publication number: 20200139879Abstract: A vehicular lamp system includes: an imager; a luminance analyzer that detects a luminance of each of multiple individual regions; an illuminance setting unit that determines an illuminance value of light emitted to each individual region, based on a detection result from the luminance analyzer; a light source unit; and a light source controller that controls the light source unit. The illuminance setting unit uses different functions to determine the illuminance value for an individual region that falls within a certain first luminance range, and the illuminance value for an individual region that falls within a certain second luminance range.Type: ApplicationFiled: December 27, 2019Publication date: May 7, 2020Applicant: KOITO MANUFACTURING CO., LTD.Inventors: Yoshinori SHIBATA, Takao MURAMATSU
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Patent number: 10641454Abstract: There is provided a vehicle lamp includes a first light source part, a second light source part, a scanning optical system which scans an emission beam from the first light source part by repeating a periodical motion, and a lighting circuit which independently drives the first light source part and the second light source part. A scanning beam scanned by the scanning optical system is projected to form a first pattern, and an emission beam from the second light source part is projected to form a second pattern.Type: GrantFiled: June 22, 2018Date of Patent: May 5, 2020Assignee: KOITO MANUFACTURING CO., LTD.Inventors: Satoshi Kikuchi, Tomoyuki Ichikawa, Takao Muramatsu
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Patent number: 10609774Abstract: A lighting circuit includes a voltage converter configured to receive a DC voltage to perform voltage conversion and supply a drive current to a light source unit including a light emitting element, a bypass switch configured to form a bypass path through which the drive current bypasses the light emitting element, and a controller configured to control the voltage converter and the bypass switch. The light source unit includes a plurality of light emitting elements connected in series. The bypass path includes at least one bypass switch which are connected in parallel with at least one of the light emitting elements. When turning on the light emitting element of the light source unit, the controller controls the voltage conversion to start in a state where the bypass switch is turned on, and then, turns off the bypass switch to turn on the light emitting element.Type: GrantFiled: July 1, 2016Date of Patent: March 31, 2020Assignee: KIOTO MANUFACTURING CO., LTD.Inventors: Toshiyuki Tsuchiya, Takao Muramatsu, Takeshi Toda
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Patent number: 10426012Abstract: There is provided a lighting circuit configured to drive a light emitting unit including a first light source and a second light source connected in series. The lighting circuit includes a first pin connected to one end of the first light source, a second pin connected to a connection node of the first light source and the second light source, a third pin connected to one end of the second light source, a drive circuit configured to supply a drive current to the light emitting unit, a bypass switch provided between the second pin and the third pin, a first resistor provided in parallel with the bypass switch between the second pin and the third pin, and an abnormality detection circuit configured to detect abnormality based on a detection voltage generated between the second pin and the third pin when an ON signal is applied to the bypass switch.Type: GrantFiled: August 16, 2017Date of Patent: September 24, 2019Assignee: KOITO MANUFACTURING CO., LTD.Inventors: Shohei Yanagizu, Masayasu Ito, Takao Muramatsu
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Publication number: 20190202344Abstract: A lighting circuit drives a light source including N (N represents an integer of 2 or more) multiple light-emitting elements coupled in series. A bypass switch circuit includes N multiple bypass switches, each coupled in parallel to a corresponding light-emitting element. A constant current driving circuit supplies a driving current stabilized to a target current to the light source. A light distribution controller controls the bypass switch circuit. For a given light distribution pattern, the duty ratio Di(%) is determined for each of the N multiple light-emitting elements. Multiple light-emitting elements are formed as control units having a sum total of duty ratios that is less than 100%. The light distribution controller controls the multiple bypass switches such that the multiple light-emitting elements included in the same control unit are not turned on at the same time.Type: ApplicationFiled: March 8, 2019Publication date: July 4, 2019Applicant: Koito Manufacturing Co., Ltd.Inventors: Yuta MARUYAMA, Kentarou MURAKAMI, Takao MURAMATSU
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Patent number: 10246004Abstract: A vehicle headlight control apparatus controls headlights of a vehicle including LEDs. The vehicle headlight control apparatus includes: drivers and each of which gradually changes a luminance of the LEDs between a predetermined on state and a predetermined off state over a switching time period; and a lamp ECU that determines the switching time period in a changeable manner.Type: GrantFiled: May 24, 2016Date of Patent: April 2, 2019Assignees: DENSO CORPORATION, TOYOTA JIDOSHA KABUSHIKI KAISHA, KOITO MANUFACTURING CO., LTD.Inventors: Ryu Mizuno, Shinichi Futamura, Tatsuya Takagaki, Takatoshi Nakagawa, Kiyotaka Mochizuki, Takao Muramatsu
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Publication number: 20190008010Abstract: A lighting circuit includes a voltage converter configured to receive a DC voltage to perform voltage conversion and supply a drive current to a light source unit including a light emitting element, a bypass switch configured to form a bypass path through which the drive current bypasses the light emitting element, and a controller configured to control the voltage converter and the bypass switch. The light source unit includes a plurality of light emitting elements connected in series. The bypass path includes at least one bypass switch which are connected in parallel with at least one of the light emitting elements. When turning on the light emitting element of the light source unit, the controller controls the voltage conversion to start in a state where the bypass switch is turned on, and then, turns off the bypass switch to turn on the light emitting element.Type: ApplicationFiled: July 1, 2016Publication date: January 3, 2019Applicants: KOITO MANUFACTURING CO., LTD., KOITO MANUFACTURING CO., LTD.Inventors: Toshiyuki Tsuchiya, Takao Muramatsu, Takeshi Toda
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Publication number: 20180372295Abstract: There is provided a vehicle lamp includes a first light source part, a second light source part, a scanning optical system which scans an emission beam from the first light source part by repeating a periodical motion, and a lighting circuit which independently drives the first light source part and the second light source part. A scanning beam scanned by the scanning optical system is projected to form a first pattern, and an emission beam from the second light source part is projected to form a second pattern.Type: ApplicationFiled: June 22, 2018Publication date: December 27, 2018Applicant: KOITO MANUFACTURING CO., LTD.Inventors: Satoshi Kikuchi, Tomoyuki Ichikawa, Takao Muramatsu
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Patent number: 10156334Abstract: A vehicular lamp is provided with a plurality of light emitting units and configured to independently control ON/OFF of the light emitting units. The plurality of light emitting units are disposed so that a desired light distribution is formed by overlapping scanning of illumination spots formed on a virtual screen by emitted lights thereof. The plurality of light emitting units are divided in a plurality of channels, the same direct drive current is supplied to at least one light emitting unit of all of the light emitting units included in the same channel, and the direct drive current is constantly maintained during a scanning period. The current amount of drive current for each channel is set in accordance with a light distribution mode, and ON/OFF of each light emitting unit is switched at a predetermined timing determined in accordance with the light distribution mode during a scanning period.Type: GrantFiled: April 20, 2018Date of Patent: December 18, 2018Assignee: Koito Manufacturing Co., Ltd.Inventors: Satoshi Kikuchi, Kentarou Murakami, Takao Muramatsu
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Publication number: 20180313508Abstract: A vehicular lamp is provided with a plurality of light emitting units and configured to independently control ON/OFF of the light emitting units. The plurality of light emitting units are disposed so that a desired light distribution is formed by overlapping scanning of illumination spots formed on a virtual screen by emitted lights thereof. The plurality of light emitting units are divided in a plurality of channels, the same direct drive current is supplied to at least one light emitting unit of all of the light emitting units included in the same channel, and the direct drive current is constantly maintained during a scanning period. The current amount of drive current for each channel is set in accordance with a light distribution mode, and ON/OFF of each light emitting unit is switched at a predetermined timing determined in accordance with the light distribution mode during a scanning period.Type: ApplicationFiled: April 20, 2018Publication date: November 1, 2018Inventors: Satoshi Kikuchi, Kentarou Murakami, Takao Muramatsu
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Patent number: 10000150Abstract: A lighting circuit drives a light source including plural light emitting elements and includes a bypass switch circuit which includes plural bypass switches connected in parallel with the plural light emitting elements, a boost converter which boosts a power supply voltage to generate a direct current voltage stabilized at a variable target voltage, a buck converter which receives the direct current voltage to supply a driving current stabilized at a target current to the light source and which includes a hysteresis controller configured to stabilize the driving current between a peak value and a bottom value and to change a difference between the peak value and the bottom value such a switching frequency of the buck converter approaches a constant value, and a voltage adjusting circuit which is configured to dynamically change the target voltage of the boost converter according to an output voltage of the buck converter.Type: GrantFiled: August 25, 2017Date of Patent: June 19, 2018Assignee: KOITO MANUFACTURING CO., LTD.Inventors: Takao Muramatsu, Satoshi Kikuchi
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Publication number: 20180168013Abstract: A lighting circuit controls lighting/extinguishing of a light source. A driving circuit generates a driving current which is to be supplied to the light source. A clamp circuit clamps a voltage between both ends of the light source to a clamp level in a period in which the light source is to be turned off. The clamp level is defined to be higher than zero and lower than a critical pressure when the light source is turned on/off.Type: ApplicationFiled: December 6, 2017Publication date: June 14, 2018Inventors: Satoshi Kikuchi, Takao Muramatsu
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Patent number: 9951920Abstract: A vehicle lamp control system is provided which can not only restrict a semiconductor light emitting element from being deteriorated or damaged by sunlight and but also maintain an illumination efficiency of the semiconductor light emitting element. The vehicle lamp control system includes a projection lens, semiconductor light emitting elements disposed near a rear focal point of the projection lens and emit light towards the projection lens, a movable shade which can move between a shading position where the movable shade cuts off light emitted from the semiconductor light emitting elements to be incident on the projection lens and a non-shading position where the movable shade does not cut off light emitting elements to be incident on the projection lens, and a headlamp control unit which executes a control in which the movable shade is moved to the shading position with the semiconductor light emitting elements left switched off.Type: GrantFiled: September 25, 2014Date of Patent: April 24, 2018Assignee: KOITO MANUFACTURING CO., LTD.Inventors: Takeshi Masuda, Michihiko Hayakawa, Takao Muramatsu, Misako Nakazawa, Hidetada Tanaka, Yuichi Shibata
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Publication number: 20180056853Abstract: A lighting circuit drives a light source including plural light emitting elements and includes a bypass switch circuit which includes plural bypass switches connected in parallel with the plural light emitting elements, a boost converter which boosts a power supply voltage to generate a direct current voltage stabilized at a variable target voltage, a buck converter which receives the direct current voltage to supply a driving current stabilized at a target current to the light source and which includes a hysteresis controller configured to stabilize the driving current between a peak value and a bottom value and to change a difference between the peak value and the bottom value such a switching frequency of the buck converter approaches a constant value, and a voltage adjusting circuit which is configured to dynamically change the target voltage of the boost converter according to an output voltage of the buck converter.Type: ApplicationFiled: August 25, 2017Publication date: March 1, 2018Applicant: KOITO MANUFACTURING CO., LTD.Inventors: Takao Muramatsu, Satoshi Kikuchi
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Publication number: 20180054870Abstract: There is provided a lighting circuit configured to drive a light emitting unit including a first light source and a second light source connected in series. The lighting circuit includes a first pin connected to one end of the first light source, a second pin connected to a connection node of the first light source and the second light source, a third pin connected to one end of the second light source, a drive circuit configured to supply a drive current to the light emitting unit, a bypass switch provided between the second pin and the third pin, a first resistor provided in parallel with the bypass switch between the second pin and the third pin, and an abnormality detection circuit configured to detect abnormality based on a detection voltage generated between the second pin and the third pin when an ON signal is applied to the bypass switch.Type: ApplicationFiled: August 16, 2017Publication date: February 22, 2018Applicant: KOITO MANUFACTURING CO., LTD.Inventors: Shohei Yanagizu, Masayasu Ito, Takao Muramatsu
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Publication number: 20180043820Abstract: A vehicular lighting device includes a scanning light source. The scanning light source includes a semiconductor light source, and scans the output light of the semiconductor light source in a forward region ahead of the lighting device. A lighting circuit changes the light amount of the semiconductor light source in multiple levels in synchronization with the scanning of the scanning light source.Type: ApplicationFiled: October 15, 2017Publication date: February 15, 2018Applicant: KOITO MANUFACTURING CO., LTD.Inventors: Kentarou MURAKAMI, Hitoshi TAKEDA, Takao MURAMATSU