US 12,107,379 B2
Laser device
Shinichi Sakamoto, Sakura (JP); Yasuto Chiba, Sakura (JP); Wataru Kiyoyama, Sakura (JP); Yutaka Yamaguchi, Sakura (JP); and Takashi Hasunuma, Sakura (JP)
Assigned to Fujikura Ltd., Tokyo (JP)
Appl. No. 17/422,267
Filed by Fujikura Ltd., Tokyo (JP)
PCT Filed Feb. 27, 2020, PCT No. PCT/JP2020/008039
§ 371(c)(1), (2) Date Jul. 12, 2021,
PCT Pub. No. WO2020/175622, PCT Pub. Date Sep. 3, 2020.
Claims priority of application No. 2019-034377 (JP), filed on Feb. 27, 2019.
Prior Publication US 2022/0094132 A1, Mar. 24, 2022
Int. Cl. H01S 3/094 (2006.01); B23K 26/70 (2014.01); H01S 3/00 (2006.01); H01S 3/067 (2006.01)
CPC H01S 3/094053 (2013.01) [B23K 26/705 (2015.10); H01S 3/0014 (2013.01); H01S 3/005 (2013.01); H01S 3/06708 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A laser device comprising:
a light source;
a delivery fiber that propagates laser light emitted from the light source;
a first light detector and a second light detector that detect a part of light propagating in a direction opposite to a propagation direction of the laser light through the delivery fiber; and
a monitor fiber that:
is optically coupled to the delivery fiber, and
propagates part of the light propagating in the direction opposite to the propagation direction, wherein
one end portion of the monitor fiber is connected to the first light detector, and
the second light detector is a Rayleigh monitor that faces an outer peripheral surface of the monitor fiber,
the first light detector detects a first light in a wavelength band of visible light, and
the second light detector detects a second light in a wavelength band of near-infrared light.