Patent ID: 7317740

Claim:
A mode locking device of fiber laser, for a fiber laser loop, to change a laser beam into a pulse laser signal in mode-locking for output, comprising: a bar structural body, having a central hollow region extending along a reference line of the bar structural body, with the two ends of the central hollow region coupled with two collimators on a fiber laser loop to form a close optical route; a polarization dependent isolator, disposed within the central hollow region of the bar structural body; a plurality of rotors, disposed within the central hollow region of the bar structural body, wherein each rotor has a protruding piece; and through the protruding pieces the rotors can be rotated along the reference line; and the laser beam can pass through these rotors along the reference line; and a plurality of retardation waveplates, respectively disposed on the rotors and rotating together with the rotors, wherein each of the retardation waveplates is adjusted to an angle, such that the laser beam can be mode-locked and output as the pulse laser signal.