公开(公告)号：US20240042544A1

公开(公告)日：2024-02-08

申请号：US18482512

申请日：2023-10-06

Applicant: GIGAPHOTON INC.

Inventor： Takuma YAMANAKA

IPC: B23K26/0622 ,  B23K26/06

CPC classification number: B23K26/0622 ,  B23K26/0643 ,  B23K26/0652 ,  B23K2101/36

Abstract: A laser device includes an oscillator outputting pulse laser light, a wavelength monitor measuring a center wavelength of the pulse laser light, and a processor. The oscillator includes a chamber including discharge electrodes applying a voltage to a laser gas in the chamber, an optical element arranged on an optical path of the pulse laser light, a drive mechanism driving a rotation stage on which the optical element is mounted, a grating, and an output coupling mirror. The processor periodically switches a target value of the center wavelength, controls the center wavelength by outputting a drive command to the drive mechanism to change an incident angle on the grating, and corrects a drive command value of the drive mechanism for outputting the pulse laser light with the same target value in a subsequent cycle based on a deviation between a measurement value of the center wavelength and the target value.

公开(公告)号：US20210294223A1

公开(公告)日：2021-09-23

申请号：US17341570

申请日：2021-06-08

Applicant: Gigaphoton Inc.

Inventor： Takuma YAMANAKA ,  Hirotaka MIYAMOTO

IPC: G03F7/20 ,  H01S3/063

Abstract: A wavelength control method of a laser apparatus includes sequentially obtaining target wavelength data of a pulse laser beam, sequentially saving the target wavelength data, sequentially measuring a wavelength of the pulse laser beam to obtain a measured wavelength, calculating a wavelength deviation using the measured wavelength and the target wavelength data at a time before a time when the measured wavelength is obtained, and feedback-controlling the wavelength of the pulse laser beam using the wavelength deviation.

公开(公告)号：US20230229088A1

公开(公告)日：2023-07-20

申请号：US18180504

申请日：2023-03-08

Applicant: Gigaphoton Inc.

Inventor： Takuma YAMANAKA

IPC: G03F7/20 ,  H01S3/225

CPC classification number: G03F7/2006 ,  H01S3/2251 ,  G03F7/201

Abstract: A laser apparatus includes an oscillator, a rotary stage that supports an optical element, a grating, a first driving mechanism that changes the angle of incidence of pulse laser light to be incident on the grating by driving the rotary stage, a second driving mechanism that changes the angle of incidence of the pulse laser light to be incident on the grating by driving the rotary stage by a smaller amount, a wavelength monitor, and a processor that cyclically changes a target wavelength of the pulse laser light. The processor calculates the moving average of drive instruction values by which the second driving mechanism is driven, and when the moving average exceeds a threshold, the processor causes the second driving mechanism to return to an initial position, and drives the first driving mechanism to cancel a change in the angle of incidence caused by the returning operation.

公开(公告)号：US20240044711A1

公开(公告)日：2024-02-08

申请号：US18487774

申请日：2023-10-16

Applicant: Gigaphoton Inc.

Inventor： Takuma YAMANAKA

IPC: G01J3/45 ,  H01S3/08

CPC classification number: G01J3/45 ,  H01S3/08086 ,  G01J2003/003

Abstract: A wavelength measurement apparatus includes a first spectrometer that has a first free spectral range and generates a first measured waveform from an interference pattern produced by a pulse laser beam, a second spectrometer that has a second free spectral range narrower than the first free spectral range and generates a second measured waveform from the interference pattern produced by the pulse laser beam, and a processor that reads data on a first measurement range of the first spectrometer, sets a second measurement range of the second spectrometer based on the data on the first measurement range, reads data on the second measurement range, and calculates a center wavelength of the pulse laser beam based on the data on the first measurement range and the data on the second measurement range.

公开(公告)号：US20210367396A1

公开(公告)日：2021-11-25

申请号：US17398084

申请日：2021-08-10

Applicant: Gigaphoton Inc.

Inventor： Hirotaka MIYAMOTO ,  Takuma YAMANAKA ,  Miwa IGARASHI

IPC: H01S3/13 ,  H01S3/038 ,  H01S3/137 ,  H01S3/08 ,  G03F7/20

Abstract: A laser apparatus includes an output coupling mirror; a grating that constitutes an optical resonator together with the output coupling mirror; a laser chamber in an optical path of the optical resonator; at least one prism in an optical path between the laser chamber and the grating; a rotary stage including an actuator that rotates the prism to change an incident angle of a laser beam from the laser chamber on the grating; a wavelength measuring unit that measures a central wavelength of the laser beam from the laser chamber through the output coupling mirror; an angle sensor that detects a rotation angle of the prism; a first control unit that controls the actuator at a first operation frequency; and a second control unit that controls the actuator at a second operation frequency.