At present, the global manufacturing industry is on the road to precision, integration and intelligence development. Micromachining technology is becoming the mainstream technology trend of precision manufacturing and has become an important research topic of all countries in the world. The application of fine processing is greatly reflected in the processing of 3C industry, including cell phone cover, backplane, PCB, lens material processing, semiconductor integration processing, and welding, cutting, punching and marking processing of high hardness, high brittleness and high melting point materials, which shows higher requirements for the processing of laser equipment.

We invited Mr. Qiu Jianrong, Director of Micro & Nano Photonics Institute, Zhejiang University to analyze“Ultrafast laser processing” from the perspective of scientific and technological progress. Femtosecond laser is a kind of ultrafast laser, ultrafast laser manufacturing is a hot trend in the field of laser manufacturing, and the Ministry of Science and Technology has launched a national key R&D program, and China has made important progress in related fields. The  focuses on the new technology of ultrafast laser manufacturing, and the exploration in femtosecond laser processing.

Femtosecond laser is already a popular segment in the industry, it has three characteristics: First, the pulse is very narrow; Second, after focusing, the light intensity at the focal point is very strong; Third, unlike continuous laser or nanosecond laser, long pulse laser, femtosecond laser corresponds to a broad spectrum in the frequency spectrum. Using these three characteristics to do processing, can complete non-thermal effects super processing, in fact, not so, femtosecond laser also has a thermal effect, which is a little slighter compared to the long pulse laser, and the thermal effect can be precisely controlled. Now the femtosecond laser processing especially in industrial applications usually ignore the thermal effect to achieve very fine cutting, punching, this market is relatively large. In addition, in medical, the main applications are in ophthalmic surgery, genetic and brain surgery, etc.

Femtosecond laser has strong focal point, which can induce multi-photon absorption, like two-photon aggregation, can be achieved by spatially selective microstructure manipulation. Because of the wide spectrum of femtosecond laser, using grating and mask to reshape the pulse of femtosecond laser, for image position and even pulse, etc., which is the controllable characteristic that other lasers do not have. Generally speaking, the femtosecond laser is used for processing, the femtosecond laser is introduced into the microscope system, focused by the lens and shines on the sample, the sample is placed on a three-dimensional adjustable platform for three-dimensional processing, and it is also known to use the oscillator to scan the light, and linking to the platform to achieve a wide range of fine laser manipulation.

This is a frequently used processing technology. First, femtosecond laser induces biased nano-grating; second, femtosecond laser manipulates the valence state of doped ions inside transparent materials and uses it for optical storage.

Mr. Qiu's team's laboratory is called Photonic Materials and Components Research Laboratory, which has three directions: glass, optical fiber, luminescent and non-mechanical materials, and one more direction is the mutual application of laser and materials. We mainly do research in two directions: first, 3D printing. We develop our own equipment and use it to do 3D printing of glass and ceramics, etc. Second, in the mutual applications of femtosecond laser and material. Our understanding of femtosecond laser is still relatively shallow. Femtosecond laser is a kind of extreme physical conditions realized in the laboratory, and it induces phenomena beyond imagination. For example, a focused femtosecond laser irradiated inside a glass or crystal will form the nanograting structure presented above.

In the future, the laboratory hopes to make complex optical paths for spectrometers and quantum computing. When the femtosecond laser irradiates, it produces the bubbles which was found to be related to the direction of laser deflection, it also controls the absorption and manipulation of quantum dots inside the material after femtosecond laser irradiates. In addition, it is possible to control the absorption and manipulation of quantum dots inside the material after femtosecond laser irradiation. This is a very important achievement. In addition, by irradiating transparent materials with femtosecond laser, it will absorb various nanoparticles in transparent materials and then form various colors, such as yellow, red, orange, blue, etc.

Femtosecond laser is really an extreme physical condition, it can be used to do a lot, not only to cut, weld and punch, it can also be used as various micro and nano photonics components in the integrated optics.

Related Sub-expo:

Lasers Technology & Intelligent Manufacturing Expo

Laser Materials & Components/aser Components, Motion and Cutting Control System, Auxiliary System/Lasers/Laser Equipment and Accessories/Laser Specialty Applications/3D Printing / Additive Manufacturing/Intelligent and Automation Equipment/Industrial Robot and Automation

Media Contact

Ethan.li

ethan.li@cioe.cn