What is the laser technology?
Laser English full name is Light Amplification by Stimulated Emission of Radiation (LASER). Available in 1960, is the enhanced light stimulates the production of radiation. (Millstone laser engraving machine).
Scientists in the power tube to light or current of energy to impact the substance of some of the crystal or atomic vulnerable excited to reach the high energy of the excited state, so that electrons in atoms, when these electrons to return to the calm, low-energy state, atoms will be photon shot to release the excess energy; Then, these emit photons will hit other atoms, to stimulate more atoms to produce photons, triggering a series of \"chain reaction\", and move forward towards the same side, form a strong and focused toward a direction of light; strong laser or even can be used as a cutting steel!
The characteristics of the laser:
The laser is widely used because of its characteristics. The laser is almost one kind of monochromatic light wave frequency range is very narrow high-energy, but also concentrated in a narrow direction, so the use of a focused laser beam to punch a variety of materials. Ruby laser, for example, the total output pulse energy is not enough to cook an egg, but a small hole drilled in the 3 mm steel plate. Laser with the above characteristics, not because it is there with a different light, but its very high power density, laser is widely used.
The laser has the following three characteristics:
· Monochromatic Wavelength
· Parallel beam
Laser processing technologies:
The laser is the new light of the 1960s. Directivity, high brightness, good monochrome laser has been widely used in laser processing is one of the most promising areas of laser applications, has developed more than 20 kinds of laser processing technology.
Laser space controlled and time controlled well, of processing the material, shape, size and processing environment of freedom, particularly suitable for automated processing. The laser processing system with computer numerical control technology combine to form a highly efficient automated processing equipment, has become enterprises timely production of key technologies, has opened up broad prospects for high quality, efficient and low-cost processing.
Thermal processing and cold can be applied in the metal and nonmetal materials, cutting, drilling, grooving, marking the thermal processing of metallic materials for welding, surface treatment, production of alloys, cutting are very favorable. Cold photochemical deposition Laser rapid prototyping technology, laser etching, doped dye and oxidation are appropriate.
Laser Rapid Prototyping:
Manufacturing model with a laser material is a liquid photosensitive resin, in the absorption of ultraviolet laser energy after coagulation, changes into a solid material. To create a model compiled program input to the computer. Laser beam to the laser output optical system controlled by computer, scan it on the model material characterization, wherever he went in the laser beam, the original is the solidification of the liquid. Finished scanning the laser beam in the computer\\ s command to make an depiction of the photosensitive polymer material layer by layer curing accurate piled into the sample, creating the model. Therefore, the manufacturing model in this way, fast, and sophisticated model made out of. The technology has been widely used in aerospace, electronics, automotive and other industrial fields.
Laser cutting technology is widely used in the processing of metallic and nonmetallic materials, can significantly reduce processing time, reduce processing costs, and improve the quality of the workpiece. Pulsed laser for metal materials, continuous laser for non-metallic materials, which is an important application field of laser cutting technology. Laser application in the industrial field limitations and shortcomings, such as using a laser to cut the food and plywood are not successful, the food is cut also was burning, cutting plywood in the economy is still far from substandard operator .
Laser beam in the material, it will heated to melting, so that the components are joined together with docking, that is welded. Laser welding than the smaller power of the laser beam cutting metal, the material to melt without it gasification become a continuous solid structure after cooling. The laser welding technology has dissolved pool purification effect, would be pure weld metal, apply to the similarities and differences between the metal material welding. Due to the high laser energy density, melting point, high reflectivity, high thermal conductivity and physical properties vary a great deal of metal welding is particularly beneficial. Using laser welding does not require any solder, and so ruled out the possibility of welding components contaminated; Second, the laser beam can be optical systems together into very thin diameter of the beam, in other words, the laser can be made very fine \"torch\" precision welding work is done; laser welding and components not in direct contact, that is, non-contact welding, and thus the material so fragile and does not matter, you can also away from our side components for welding, can also be placed in the vacuum chamber components welded together. Laser welding of these characteristics, so it is particularly popular in the microelectronics industry.
Engraving, laser graver than ordinary chisel is more convenient and rapid. Ordinary chisel in hard materials, such as granite, steel plate for engraving on, or in some soft material, such as leather to make carving more difficult, engraved with a pattern takes a long time . If the use of laser engraving is different, because it is the use of high energy density laser local irradiation of the workpiece, so that the surface material gasification or color change of the chemical reaction occurs, thus leaving a permanent mark an engraving method. It does not have contacts and materials, materials, hard or soft, does not hinder the speed of the carving. Laser engraving technology is one of the largest areas of application of laser processing. Regardless of the speed of a hard material, or carved in the soft materials, depicts this chisel for carving. If compatible with the computer to control the laser beam moves, the carving can also be automated. Patterns to be carved on the optical scanner, the scanner output signal after computer processing, used to control the action of the laser beam can be automatically in the wood, glass, leather, according to our pattern carved out . The same time, focusing the laser beam up very fine, equivalent to a very smart graver lines and fine carved details on the pattern to be carved out. Laser engraving can play a variety of text, symbols and patterns, the character size from millimeters to micrometers, which is the security has a special meaning. The laser engraving is already development in recent years to achieve sub-micron engraving, has been widely used in the microelectronics industry and biological engineering.
Open a small hole in the component is a very common thing. However, if you require a hard material, such as a large number of 0.1 millimeters to a few microns diameter holes to play in the cemented carbide. Ordinary machining tools probably is not an easy task, even if able to do the processing costs will be high. Good laser coherence, with the optical system, it focused into a marginal spot diameter (less than one micron), which is equivalent to \"micro-drill used for drilling. Secondly, the high brightness of laser on the focus of the focused laser energy density (the average energy per square meter) will be high, and an ordinary laser output laser, the energy generated can be as high as 109 J / cm 2 enough to allow the material melting and gasification, leaving a small hole in the material, like a drill out. However, the laser drilled hole is conical, rather than mechanical drilling cylindrical, in some places is very convenient.
Laser etching technology is simpler than the conventional chemical etching process, can greatly reduce production costs, can be processed from 0.125 to 1 μm wide line, very suitable for the manufacture of ultra-LSI.
The Laser future development
The laser can produce high-energy, precise focus of the monochromatic light, with some penetration, role in human tissue in the local high heat. Laser surgery is the use of this feature of the laser, removal or destruction of the target tissue to achieve the purpose of treatment. Including laser cutting and laser resurfacing.
The laser weapon has its uniqueness, it is widely used in air defense, anti-tank, bomber self-defense and military purposes. Laser is able to become a powerful weapon, because it has three levels of destructive capability:
An ablation effect with the principle of laser thermal processing, when the high-energy laser beam hitting the target, the energy of the laser target materials absorbed into heat, heat enough to make the target partial or complete perforation, fracture, melting, evaporation , or even an explosion.
Compression wave. Shock effects such as target material vaporized target material produce recoil effect in a very short period of time, the formation of surface spall broken open, debris outward flight, causing further damage.
Radiation effect of the target material gasification while the formation of a plasma cloud, can produce ultraviolet radiation and X-ray, so that the target within the electronic components to be destroyed.
The laser can also be used in nuclear power generation. Now completed the world\\ s nuclear power plants use nuclear fuel is uranium, tritium nuclear fuel studies have not been successful. From the study of tritium nuclear fuel than uranium nuclear fuel is more resistant to burning 1 kg of tritium nuclear fuel combustion to produce energy more than three times higher than that of uranium nuclear fuel. More attractive is the storage of tritium nuclear fuel on Earth. 1 kg of seawater contains 0.03 grams of tritium, loaded with 1021 kg of sea water on Earth\\ s oceans; or on storage in the Earth\\ s oceans 1017 kg of tritium, it developed a fuel, equivalent to that provided us with 10 trillion billion (1017) tons of coal, enough for a human to spend hundreds of millions of years, since the tritium nuclear fuel is so good why are not? The problem is that the ignition and burning is not an easy thing. Draw a match and burning temperature to fire the pieces of paper, gasoline point to make the nuclear fuel on fire, you will need one hundred million degrees of heat. The laser is more likely to reach the ignition temperature technology.