In recent years, the rapid development of high-speed rail, nuclear power, shipbuilding, petrochemical and aerospace and other fields of our country, put forward higher demand for laser cutting processing equipment and technology, the general trend is towards higher power, faster, more and more thick format cutting section, brighter and more straight the direction of development. At present, the development of laser industry is more and more active. Fiber laser power technology and optical components technology constantly break through. It will promote the installed power of laser cutting machine.
To solve the technical problems of the beam transmission of high power laser equipment is also very important. Due to optical processing capacity constraints, it is difficult to fabricate optical components shaping effect is good, high diffraction limit, to a certain extent, restricts the development of high power laser transmission technology, how to improve the optical surface polishing technology, optical device for high diffraction efficiency of producing ability is the future development and application of ultra high power laser challenge. High power laser power from the fiber core 100 m diameter inner injection, its power density in general, as can be imagined, composed by the laser transmission path through the fiber end mirror, QBH or QD interface, collimation lens, zoom lens, a focusing mirror and a mirror under protection, given the ultra high power density all of the above, the optical lens on the path of cleanliness and the temperature rise of the stringent requirements, the optical path must be strictly sealed, there shall be no medium exchange with the outside world, and shall be installed in the clean room and clean optical devices, in addition the link cooling loop pressure and flow, the water inlet and the water temperature sequence and are equally important. To ensure that the temperature of cutting process remained relatively constant. Generally speaking, there must be a laser cutting knife hole, especially cutting plate materials, perforation quality is very important, good perforation is the foundation to ensure the stability of light and air, high power laser cutting, zoom perforation technology is relatively distance control beam expanding lens and a focusing lens group with servo motor, realize the change the focal spot of positive and negative defocus, cutting of stainless steel, aluminum, brass and copper and Aluminum Alloy need negative defocus, the greater thickness of negative defocus deeper (Figure 1). The servo control "double - Double - biconcave" ZOOM lens group, realize the classification or stepless focusing (Figure 2), a high-speed dynamic zoom perforation, realize the slotted section cutting slope. Beam cutting technology, mode automatic transformation control technology and energy density calculus technology are adopted to achieve the "bright surface cutting" of stainless steel and high reflective materials with large thickness.