Patents Assigned to Megaopto Co., Ltd.
  • Patent number: 9001416
    Abstract: The invention relates to a pulsed light source capable of effectively utilizing optical power and selecting the pulse width of output pulsed light. A pulsed light source has a MOPA structure, and comprises a seed light source and an optical fiber amplifier. The seed light source includes a semiconductor laser outputting pulsed light. In the optical fiber amplifier, an optical filter branches pulsed light amplified by a YbDF into a first wavelength component including the peak wavelength and the remaining second wavelength component. An optical switch outputs one of the pulsed light of the first wavelength component and the pulsed light of the second wavelength component which are inputted. Another YbDF amplifies the pulsed light outputted from the optical switch.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: April 7, 2015
    Assignee: Megaopto Co., Ltd.
    Inventor: Motoki Kakui
  • Patent number: 8995479
    Abstract: The present invention relates to a laser apparatus having a structure for removing a skirt portion contained in pulsed light, and a laser processing method using the laser apparatus. The laser apparatus comprises a MOPA fiber laser light source which outputs pulsed light having a skirt portion with a light intensity lower than a predetermined value, and a saturable absorber which removes a skirt portion from the pulsed light outputted from the MOPA fiber laser light source.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: March 31, 2015
    Assignee: Megaopto Co., Ltd.
    Inventors: Yasuomi Kaneuchi, Motoki Kakui
  • Patent number: 8902940
    Abstract: The present invention relates to a light source control method capable of decreasing the dependence of a pulse width (FWHM) of an output pulsed light on a repetition frequency. A pulsed light source has an MOPA structure, and has a seed light source and an optical fiber amplifier. The seed light source includes a semiconductor laser which is directly modulated and outputs a pulsed light. By adjusting a temperature of the seed light source and a pumping light power of the optical fiber amplifier, a predetermined full width half maximum of a pulse at a predetermined repetition frequency is implemented for the pulsed light outputted from the optical fiber amplifier.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: December 2, 2014
    Assignee: Megaopto Co., Ltd.
    Inventors: Motoki Kakui, Shinobu Tamaoki
  • Patent number: 8891565
    Abstract: The pulse light source comprises a semiconductor laser outputting pulse light, an optical filter, and an optical amplifier. The optical filter outputs a chirping component of the inputted pulse light, by adjusting a relative position of a transmission spectrum of the optical filter with respect to an output spectrum of the seed light source.
    Type: Grant
    Filed: October 28, 2013
    Date of Patent: November 18, 2014
    Assignee: Megaopto Co., Ltd.
    Inventor: Motoki Kakui
  • Patent number: 8767292
    Abstract: The present invention relates to a laser apparatus capable of supplying laser beams from each of plural beam emitting ends constituting laser beam output ports, and realizes the overall low power consumption and low non-linearization. The laser apparatus comprises a seed light source, beam emitting ends, an intermediate optical amplifier, an optical branching device, and final-stage optical amplifiers. The number of beam emitting ends is greater than the number of seed light sources, and the final-stage optical amplifiers and the beam emitting ends correspond to each other one-on-one. The optical branching device includes an input port associated to the seed light source and plural output ports associated to the respective beam emitting ends so as to constitute a part of the light paths between the seed light source and the beam emitting ends.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: July 1, 2014
    Assignee: Megaopto Co., Ltd.
    Inventors: Shinobu Tamaoki, Motoki Kakui
  • Patent number: 8693514
    Abstract: The present invention enables simultaneous setting or automatic setting of a pulse peak and a pulse width of a light pulse. In a configuration comprising a light emitting element outputting laser light, a driving current supply section supplying a driving current to the light emitting element, a modulator applying a modulation voltage for pulse modulation of the laser light to the light emitting element, and a modulation control section controlling a modulation pattern as a pattern of pulse modulation of the modulation voltage for the modulator, the modulation control section sets a modulation voltage value in the modulation pattern based on information on a driving current value, and sends information on the modulation pattern to the modulator so that the modulation voltage reaches the set value.
    Type: Grant
    Filed: April 7, 2010
    Date of Patent: April 8, 2014
    Assignee: Megaopto Co., Ltd.
    Inventor: Shinobu Tamaoki
  • Publication number: 20140050238
    Abstract: The pulse light source comprises a semiconductor laser outputting pulse light, an optical filter, and an optical amplifier. The optical filter outputs a chirping component of the inputted pulse light, by adjusting a relative position of a transmission spectrum of the optical filter with respect to an output spectrum of the seed light source.
    Type: Application
    Filed: October 28, 2013
    Publication date: February 20, 2014
    Applicant: Megaopto Co., Ltd.
    Inventor: Motoki Kakui
  • Patent number: 8599888
    Abstract: The pulse light source comprises a seed light source, a first YbDF, a band-pass filter, a second YbDF, and a third YbDF, and has the MOPA structure. The band-pass filter inputs pulse light which is outputted from the seed light source and amplified by the first stage YbDF, and outputs, while separating a wavelength band of the inputted pulse light into a shorter wavelength side and a longer wavelength side with reference to a peak wavelength of the inputted pulse light, the attenuated pulse light after attenuating the optical power on one side more than the optical power on the other side between the shorter and longer wavelength sides.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: December 3, 2013
    Assignee: Megaopto Co., Ltd.
    Inventor: Motoki Kakui
  • Patent number: 8493653
    Abstract: The present invention relates to an optical fiber amplifying module equipped with a structure for stably attaining a high gain even when amplifying light having a low duty cycle. The optical fiber amplifying module comprises at least three amplification optical fibers successively arranged from an input connector to an output collimator. A bandpass filter is arranged between the first- and second-stage amplification optical fibers. Control means having a structure constituted by optically passive components alone or a feedback structure functions so as to render an upper limit to a gain for input light in the first-stage amplification optical fiber, thereby preventing the deterioration in performances such as destruction of the bandpass filter from occurring in optical components positioned on the upstream side of the final-stage amplification optical fiber.
    Type: Grant
    Filed: November 17, 2011
    Date of Patent: July 23, 2013
    Assignee: Megaopto Co., Ltd.
    Inventor: Motoki Kakui
  • Patent number: 7961378
    Abstract: A wavelength conversion light source apparatus includes a fundamental wave light source configured to emit a fundamental wave, a nonlinear crystal configured to convert a wavelength of the fundamental wave by being irradiated with the fundamental wave and making the fundamental wave pass therethrough, and a movement unit configured to place the nonlinear crystal thereon and continuously move the nonlinear crystal within a plane, where a phase matching condition is not violated, so that a passage path of the fundamental wave passing through the nonlinear crystal is changed.
    Type: Grant
    Filed: November 3, 2009
    Date of Patent: June 14, 2011
    Assignees: Megaopto Co., Ltd, Kabushiki Kaisha Toshiba, NEC Corporation
    Inventors: Shinichi Imai, Yoshiharu Urata
  • Patent number: 7755745
    Abstract: A coherent Doppler lidar which can oscillate high energy pulses and output laser beams in a longer wavelength range of 1.5 ?m to the atmosphere is provided. The coherent Doppler lidar has a pulse laser an oscillation wavelength of which is controlled by means of injection locking of a seed light output from a master laser, wherein the pulse laser is a type in which a laser medium is disposed in a resonator, a pulse light of a predetermined repetition frequency is input to the laser medium as an excitation light, whereby pulse laser oscillation is generated in the resonator to output pulse laser beams from the resonator, and the laser medium being a type which has at least a region having Tm, Ho:YAG ceramics, and is excited by the excitation light to output pulse laser beams in 2 ?m wavelength band.
    Type: Grant
    Filed: June 30, 2008
    Date of Patent: July 13, 2010
    Assignees: Megaopto Co., Ltd., National Institute of Information and Communications Technology
    Inventors: Yoshiharu Urata, Satoshi Wada, Kohei Mizutani
  • Publication number: 20100128343
    Abstract: A wavelength conversion light source apparatus includes a fundamental wave light source configured to emit a fundamental wave, a nonlinear crystal configured to convert a wavelength of the fundamental wave by being irradiated with the fundamental wave and making the fundamental wave pass therethrough, and a movement unit configured to place the nonlinear crystal thereon and continuously move the nonlinear crystal within a plane, where a phase matching condition is not violated, so that a passage path of the fundamental wave passing through the nonlinear crystal is changed.
    Type: Application
    Filed: November 3, 2009
    Publication date: May 27, 2010
    Applicants: Advanced Mask Inspection Technology, Inc., Megaopto Co., Ltd.
    Inventors: Shinichi IMAI, Yoshiharu URATA
  • Publication number: 20090073417
    Abstract: A coherent Doppler lidar which can oscillate high energy pulses and output laser beams in a longer wavelength range of 1.5 ?m to the atmosphere is provided. The coherent Doppler lidar has a pulse laser an oscillation wavelength of which is controlled by means of injection locking of a seed light output from a master laser, wherein the pulse laser is a type in which a laser medium is disposed in a resonator, a pulse light of a predetermined repetition frequency is input to the laser medium as an excitation light, whereby pulse laser oscillation is generated in the resonator to output pulse laser beams from the resonator, and the laser medium being a type which has at least a region having Tm, Ho:YAG ceramics, and is excited by the excitation light to output pulse laser beams in 2 ?m wavelength band.
    Type: Application
    Filed: June 30, 2008
    Publication date: March 19, 2009
    Applicants: MEGAOPTO CO., LTD., NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY
    Inventors: Yoshiharu URATA, Satoshi WADA, Kohei MIZUTANI
  • Publication number: 20060239324
    Abstract: A stable wavelength selecting action is realized by controlling a laser wavelength to permit a fast wavelength sweeping without mechanically turning a heavy-mass member. A laser device comprising a laser resonator including a mirror (12) having a specified transparency and an adaptive optics (10) provided with a mirror capable of controlling the reflection angle and wavefront of a reflection light and allowing an incident light to reflect by applying an active change to it, a laser medium (14) disposed inside the laser resonator, and a dispersion element (16) for receiving an output light from the laser medium.
    Type: Application
    Filed: December 9, 2003
    Publication date: October 26, 2006
    Applicants: RIKEN, MEGAOPTO CO., LTD.
    Inventors: Kazuyuki Akagawa, Satoshi Wada
  • Publication number: 20060165135
    Abstract: A saturable absorber functioning as a Q-switch is disposed on a path of a light in a laser resonator provided with a laser medium, the saturable absorber disposed in the laser resonator is transferred relatively toward the path of the light, and an initial transmittance of the saturable absorber in the case when the light passes through the saturable absorber is changed in order to achieve such effect that a scale of the whole equipment is not upsized, it is in excellent in workability and convenient, besides there is no fear of decreasing stability in a pulsed laser oscillation.
    Type: Application
    Filed: December 21, 2005
    Publication date: July 27, 2006
    Applicants: RIKEN, MEGAOPTO CO., LTD.
    Inventors: Takayo Ogawa, Satoshi Wada, Yuji Oki, Yoshiharu Urata
  • Patent number: 6937630
    Abstract: To provide a laser oscillation method and a laser device, which use a laser medium such as an Nd:GdVO4 crystal to which neodymium is doped in high concentration exceeding 1% in atomicity ratio, the laser medium comprised of the gadolinium-vanadate crystal to which neodymium as laser active ion is doped by a floating zone method such that concentration becomes exceeding 1% in atomicity ratio.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: August 30, 2005
    Assignees: Riken, NEC Tokin Corporation, Megaopto Co., Ltd.
    Inventors: Satoshi Wada, Takayo Ogawa, Hideo Tashiro, Hiroshi Machida, Mikio Higuchi, Kohei Kodaira, Tomohiro Shonai