公开(公告)号：US20200083661A1

公开(公告)日：2020-03-12

申请号：US16684040

申请日：2019-11-14

Applicant: FURUKAWA ELECTRIC CO., LTD.

Inventor： Koji KAJIWARA ,  Takeshi TAKAGI ,  Kousuke KASHIWAGI ,  Kazuaki HYUGA ,  Yoshihiro EMORI

IPC: H01S3/13 ,  H01S3/067 ,  G02B6/255 ,  H01S3/00 ,  G02B6/26 ,  H01S3/102

Abstract: An optical fiber laser device generates laser light by using an optical amplifying fiber as an amplification medium in a laser oscillator and includes: an optical outputting fiber configured to emit laser light to an outside; a return-light-attenuating portion configured to perform an attenuation process to return light propagating through at least the optical outputting fiber in a reverse direction of the laser light; a thermal conversion unit provided at the return-light-attenuating portion and configured to convert the return light into heat; a temperature-monitoring device configured to measure an increase in a temperature, of the return-light-attenuating portion, caused by the heat converted by the thermal conversion unit; and a control unit configured to decrease or stop an output of the laser light when the temperature measured by the temperature-monitoring device becomes a predetermined threshold temperature or higher.

公开(公告)号：US20170110847A1

公开(公告)日：2017-04-20

申请号：US15393709

申请日：2016-12-29

Applicant: FURUKAWA ELECTRIC CO., LTD.

Inventor： Koji KAJIWARA ,  Takeshi TAKAGI ,  Kousuke KASHIWAGI ,  Kazuaki HYUGA ,  Yoshihiro EMORI

IPC: H01S3/13 ,  H01S3/067

Abstract: An optical fiber laser device generates laser light by using an optical amplifying fiber as an amplification medium in a laser oscillator and includes: an optical outputting fiber configured to emit laser light to an outside; a return-light-attenuating portion configured to perform an attenuation process to return light propagating through at least the optical outputting fiber in a reverse direction of the laser light; a thermal conversion unit provided at the return-light-attenuating portion and configured to convert the return light into heat; a temperature-monitoring device configured to measure an increase in a temperature, of the return-light-attenuating portion, caused by the heat converted by the thermal conversion unit; and a control unit configured to decrease or stop an output of the laser light when the temperature measured by the temperature-monitoring device becomes a predetermined threshold temperature or higher.