Ultrafast Laser Machine Based on All-Fiber Femtosecond Laser System

Abstract

A femtosecond laser machine consisting of femtosecond fiber laser, trepanning head, linear motor stages system and Siemens 840D system has been integrated for industry application. The femtosecond laser source is all fiber system which contains a fiber mode-lock laser at 1053 nm with a repetition rate of 3.9 MHz, a double-cladding gain fiber amplifiers and a PCF amplifier. An acoustical modulator has employed to tune repetition rate from 3.9 MHz to 100 KHz. An in-line fiber chirped grating is used to stretch the pulse duration to 700 ps. After the PCF amplifier pulse is compressed to sub-ps with 50% efficiency based two grating compressor. The system outputs an average power of 15 W at 100 KHz and 800 fs. Using four wedges trepanning head, cylinder hole is drilled in 1mm thickness SiC ceramics in 30 s.

High-energy femtosecond Yb-doped all-fiber monolithic chirped-pulse amplifier at repetition rate of 1 MHz

“…[6] Additionally, pulse energy with an millijoule level at hundreds of kHz repetition rate with subpicosecond pulse duration has also been reported using Ybdoped large core photonic crystal fiber [7] in a complicated structure as a result of the coupling of the seed and pump laser into the gain fiber by use of an aspherical and/or spherical focusing lens. [8][9][10][11] However, with the increasing requirements for the reliable and stable performance, fiber lasers with a conventional grating stretcher and challenging free space coupling technique cannot satisfy the demand of practical applications due to the instability caused by the grating stretcher and ultraclean maintenance and treatment of fiber ends. Together with the development of the fabrication technique of various fiber-based optical components, the fiber lasers are improved by integration to be robust and have easy operation through advanced fiber fusing splicing technology.…”