OPTICAL FIBER LASER DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an optical fiber laser device capable of measuring the intensity of a laser beam highly accurately.SOLUTION: There is provided an optical fiber laser device from which a laser beam including a first wavelength and a second wavelength is output. The optical fiber laser device comprises: a branch element which branches the laser beam input from an input port into an output laser beam to an output port and a detection laser beam to a detection port; a detector which photoelectrically converts the detection laser beam into photoelectric current; and a wavelength-dependent element which is provided between a detection port of the branch element and the detector, and has different transmittances between the first wavelength and the second wavelength. The optical fiber laser device cancels a transmittance difference between the first wavelength and the second wavelength from the input port to the detection port in the branch element, and a transmittance difference between the first wavelength and the second wavelength in the wavelength-dependent element.