Review and Prospect of Laser Engraving Machine

The word "laser" is a free translation of "laser". Laser was originally a special term composed of optical amplification prefixes of stimulated emission, which was translated into "laser", "laser" and "optical stimulated emission amplifier" in China. 1964, Academician Qian Xuesen proposed to name it "laser", which not only embodies the scientific connotation of "stimulated radiation", but also shows that it is a strong new light source, which is appropriate, vivid and concise, and has been unanimously recognized by the scientific community in China and is still in use today.

Since 196 1 announced the successful development of China's first laser, with the joint efforts of laser research, teaching, production and use units across the country, China has formed a laser science and technology field with complete categories, advanced level and wide application, and made gratifying progress in industrialization, making positive contributions to China's science and technology, national economy and national defense construction, and winning a place in the world. The cause of laser science and technology has been highly valued by leaders and scientific management departments from the beginning. At that time, Zhang Jinfu, vice president of China Academy of Sciences, put forward the idea of establishing a professional laser research institute, which was quickly approved by the State Science and Technology Commission and the State Planning Commission. Vice Premier Nie, who is in charge of scientific and technological work, also specifically instructed that the institute should be built in Shanghai, which has a good industrial foundation and is conducive to the development of this new technology.

1964, Shanghai Institute of Optics and Fine Mechanics (referred to as "Shanghai Institute of Optics and Fine Mechanics"), the first specialized research institute of laser technology in China and even in the world, was established. In February of that year, the National Laser Conference was held in Shanghai, attended and presided over by Zhang Jinfu and Yan Jici, and 140 delegates submitted 103 academic reports.

Key projects, such as "6403" high-energy Nd: glass laser system started in 1964, high-power laser system and nuclear fusion research started in 1965, and development of 15 military lasers formulated in 1966, have strongly promoted and promoted the development of laser technology in China due to their comprehensive technology and great difficulty. Although China's laser science and technology industry suffered the catastrophe of the Cultural Revolution for ten years, with the support of key projects, it still survives tenaciously and has made valuable progress. "6403" high-energy Nd: glass laser system was started in 1964. Finally, it is technically judged that thermal effect is the fundamental technical obstacle, and it is unloaded at 1976. This project has made a historic contribution to the development of high-energy laser technology, which has raised the level of laser technology in China to a higher level. The main achievements are as follows: A large-aperture (1.20 mm) oscillation amplification laser system with engineering scale has been built, with the maximum output energy reaching 320,000 Joules; The beam quality is improved to 30,000 Joules. The technical integration of the system is realized, and the shooting experiment is successfully carried out. The 80mm aluminum target was penetrated at indoor10m, and the 0.2mm aluminum harrow was penetrated at 2km outdoor. The biological effect and material failure mechanism of intense laser radiation are systematically studied. The phenomenon and mechanism of light damage to the laser system itself by strong light are revealed for the first time. The importance and physical connotation of laser beam quality are deeply understood for the first time. A series of innovative technologies, such as 10000 Joule unstable cavity laser, flat-plate laser, oscillating-scanning amplification laser system and wedge beam quality diagnosis, are adopted to improve the beam quality. Breakthrough progress has been made in laser components and supporting technologies, such as low absorption and high uniformity Nd glass melting process, high-energy pulsed xenon gas, high-strength dielectric film, and large-aperture (1.2m) optical precision machining. A number of technical backbone teams have been trained and brought up. High-power laser system and nuclear fusion research 1964 Wang independently proposed laser nuclear fusion initiative, and began research on 1965. After several years' efforts, a nanosecond laser device with output power of 10 (superscript 10) watts was built, and neutrons were first generated on low-temperature deuterium target, normal-temperature lithium deuterium target and deuterated polyethylene in May 1973. 1974 successfully developed the first multi-pass chip amplifier in China, which increased the laser output power by 10 times and the neutron yield by an order of magnitude. After the principle of international centripetal compression was declassified, 1976 actively followed up and developed a six-beam laser system to irradiate the inflatable glass shell target, and the volume compression was nearly 100 times. This series of major breakthroughs has enabled China's laser fusion research to enter the advanced ranks in the world and laid the foundation for long-term sustainable development in the future. Military Laser Research1966 65438+In February, the Commission of Science, Technology and Industry for National Defense held a military laser planning meeting, attended by more than 30 people from 48 units/KLOC-0. The meeting made a development plan including 15 laser complete machine and 9 supporting technologies. Although the Convention has not been formally ratified, it has played a useful role in promoting it. In the following years, some important achievements appeared in this field. For example, the preliminary experiment of laser ranging technology in shooting range is successful: using YAG Q-switched laser with repetition frequency of 20 Hz, the ranging accuracy is better than 2 meters, and the maximum measuring distance is 660 kilometers. Adding it to the theodolite can realize the single station orbit determination of the flying target. This achievement creates the necessary conditions for completing the ballistic measurement of intercontinental missile reentry phase in the future. Ruby laser satellite ranging: American experimental satellites Expl-27, EXPL-29 and EXPL-36 have successfully measured, with the longest measurable distance of 2,300 kilometers and the accuracy of about 2 meters. This is the result of the first generation of satellite ranging, which lays the foundation for the future satellite ranging with longer distance and higher accuracy. Ruby lidar and airborne infrared lidar realized the tracking and ranging of ground-to-air and air-to-air aircraft for the first time. Laser aerial survey instrument: combining laser rangefinder and aerial camera, aerial survey is carried out on the plane to complete the mapping of complex terrain such as remote areas. The repetition rate is 6 times/minute, and the ranging accuracy is1m. Ground gun laser rangefinder: it can independently complete the functions of observation, ranging, angle measurement (direction and height angle), magnetic needle orientation and so on. The ranging range is 300-10000m, and the accuracy is 5m. In laser applications, Nd:YAG laser communication (3- 12 channel), He-Ne laser communication and single/three channel semiconductor laser communication have been successful in communication experiments. Nd:YAG laser scalpel, CO2 laser scalpel, laser iridectomy instrument and other medical equipment have also been put into use. Laser holography, the application of laser holography in plane photoelasticity, pulsed laser dynamic holography and Raman spectrophotometer have become new means of metrology science; Numerical control laser cutting machine, laser collimator, laser separation of isotope sulfur, liquid laser for agricultural research, large screen navigation display and other achievements have also been applied in industry and agriculture. At the National Science Conference held in March 1978, nearly 80 laser projects won prizes, including 70 civilian products and 10 military products, which fully reflected the achievements of laser technology development in China during this period. Although the embryonic form of laser industry appeared in processing (laser drilling), medical equipment, ranging, etc. as early as the 1960s, it was only a small amount of scattered R&D and production at that time, which failed to form a climate. Only after the reform and opening up, especially under the policy guidance of "developing high technology and realizing industrialization", did China have a real laser industry.

1987 1, China optical industry association was established, and later renamed as China optical optoelectronics, with a laser branch. According to 1998 industry association's investigation and statistics on China's laser industry, there are about 100 major laser product production units in China, with 6,400 employees and per capita sales of125,000 yuan, mainly distributed in Hubei, Beijing, Shanghai and other places. China's laser industry grew from 1.988/billion yuan to 1 .998/800 million yuan, with an average annual growth rate of 22.3%. The total sales amount is1.200 million yuan. 65,438+0,998 exported $65,438+0,200,000, accounting for 65,438+0,654,38+0.6% of the total value.

According to the usual classification method in the world, laser products include various laser instruments and equipment in laser processing, medical treatment, printing, optical storage, ranging collimation, detection, entertainment and education, laser devices and laser components for communication, and laser materials, components and assemblies. 1 1. In China, the largest sales volume is laser ranging and collimation, and the fastest development is laser processing (YAG laser processing equipment has increased at a rate of 46%-60% in recent two years, reaching 90 million yuan, surpassing CO2 laser processing equipment). The laser medical market developed earlier, once grew at a high speed, and now it is at a low point, with sales hovering at 55 million yuan. The market of high-end products is almost completely occupied by foreign products, but the TD-98 Q-switched ruby laser therapy machine developed by Tianjin University won by quality, passed FDA certification and was exported in batches. The laser classification of 1998 shows that solid-state lasers account for 37.4%, and semiconductor lasers account for 18.5%, showing the trend of vigorous development of solid-state laser market and rapid growth of semiconductor lasers. Diode-pumped solid-state lasers (pulsed, continuous, single-mode frequency stabilization, microchip, frequency doubling) will become new growth points.

Due to historical reasons, our laser research strength is relatively strong, and the laser industry is still in its infancy. How to seize the opportunity in the social transformation period and vigorously promote the development of China's laser industry, and occupy more shares in the domestic and foreign markets, is a glorious and arduous task before the vast number of laser workers. After 38 years' efforts, the laser technology in China has a relatively solid technical foundation and trained a high-quality team. This team is distributed in scientific research, universities, industrial departments, enterprises and localities, and has thousands of scientific and technological personnel, including a group of outstanding young scientists who have returned to China after their studies and more than 20 academicians of the two academies. It can be predicted that in 2 1 century, China's laser technology will have more brilliant development. In the fields of ICF laser driver, high-power chemical laser, semiconductor pumped solid-state laser, ultra-short and ultra-strong laser, laser ranging and monitoring, artificial crystal and laser industry, Chinese laser scientists and technicians will be determined to innovate and climb the peak bravely.