Laser marking Principle and Application of Technology

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Laser marking Principle and Application of Technology
Laser light is a common and coherent entirely different light source, due to high direction and high single-color and high-energy characteristics, since the early 1960s has appeared on the cause for concern. In laser printing to the owners in Applied Computer-to-plate systems, laser imagesetters, laser printers, holographic image printing, electronic publishing, laser tag printing, and so on. Among them, laser tag laser printing has been accounted for 45.3 percent of the processing industry, and in the field of application is still evolving and expanding.
Laser tag printing, also known as laser marking, laser printing standard in recent years in the field of printing, packaging, such as printing, paper printing, security printing in the application of more and more, and some have been used in the production line. This article introduced the system of laser printing technology tags and related equipment.

Laser marking Principle printing
Laser tag is printed through laser marking machine to achieve the printing machine, its basic principles is that generated by the laser generator of high-energy laser beam in a row, when the laser printer on the role of the material, in the ground state of the atomic transition to a higher energy state ; At a higher energy state of the atom is unstable, and will soon return to the ground state, when the atoms return to the ground state, quantum or photon will be released in the form of extra energy by converting solar energy to heat, so that the surface of materials Melt the moment, and even gasification to form the graphic tag.

1. Laser generator

Will be below krypton laser light marking system as an example to show the principle of laser generator. Krypton lamp after the electricity to 20kV high-voltage breakdown in the light krypton krypton gas, power supply output voltage automatically converted to 100V (5A), krypton lamps to maintain a continuous arc discharge. In the laser generator, krypton lamp at the oval cavity of a condenser focus, krypton arc of light generated by the condenser reflector cavity, and then all the focus on another focus - YAG crystal (YAG) on , YAG absorption pump, the formation of the 1060nm wavelength of the laser in a row, in a row in the laser cavity in the axis perpendicular to the mirror before and after the inter-oscillation between, and the output mirror in the past.

2. Marking Principle

RF drive (RFDriver) control of Q-switch of the switch, for Q-switch laser in the role, into a peak power up to 110kW pulse of light, the light through the hole pulsed light to reach the threshold, the output reached the cavity expansion Beam, beam by beam extended zoom lens to scan mirror after the transfer, servo motor driven by the X-axis, Y axis of rotation for optical scanning lens to scan and finally by plane market focus will be to further enlarge the power of the laser, focus on the work of plane On marking. The whole process by a computer program by.

3. Laser characteristics of the subject

Laser Marking Machine because of the special working principle, the traditional way of marking (printing, Penma, electricity and corrosion, etc.), have many advantages;

1) non-contact processing
Can be any rules or irregular surface print marking, and marking will not work after the stress;
2) applies to a wide range of materials
In metal, plastics, ceramics, glass, paper, leather and so on a different type or print on the hardness of the material;
3) production line with the integration of other equipment to improve production line automation;
4), marking a clear, durable, beautiful and effective anti-counterfeiting;
5) long-and pollution-free;
6) the cost of running low
Marking is fast and forming a tag, small power consumption and thus lower operating costs.
While the laser marker of investment in equipment than the traditional markers of equipment, but running costs, the use of laser marking confidential lower.
�� plastic transistor marking: marking machine at work 10 / s, if the depreciation of equipment to 5-year period, marking a cost of 0.00048 yuan / month. If the use of printing machines, which cost about running an integrated 0.002 yuan / month, or even higher.
�� bearing Marking the surface: If the three sub-bearing type, a total of 18 4 of the word, using galvanometer-marking, krypton lamp to the lamp life of 700 hours, each bearing the cost of a comprehensive marking To 0.00915 yuan. The cost Corrosion electric lettering is about 0.015 yuan / month. Annual output to 4,000,000 sets of bearings terms, marking only one, at least 1 year to reduce costs about 65,000 yuan.
7) processing efficiency
Computer-controlled laser beam can be mobile high-speed (the speed of 5 to 7 m / s), marking the process can be completed within a few seconds. A standard computer keyboard of the printing can be completed within 12 seconds. Laser Marking Systems equipped with a computer control system, and can be adaptable to high-speed lines.
8) the development of fast
As the laser technology and computer technology, as long as the user on the computer can be programmed laser print output and are free to transform print design, a fundamental alternative to the traditional mold of the production process in order to shorten the product cycle of upgrading and flexible production Provides a convenient tool.
9) high-precision machining
Laser beams can be very fine in the role of the material on the surface, the fine could reach a wide 0.05mm. To increase the precision processing and security features to create a broad application space.
Laser-printed to meet the standard in small plastic parts produced on a large amount of data. For example, the request can be produced more accurate, higher-resolution 2-D bar code, and stamping or marking jet way, for the purpose of enhancing market competitiveness.
10) low maintenance costs
Laser Marking the non-contact marking, unlike the standard process templates and India have a service life of the restrictions in the processing volume of very low maintenance costs.
11) with environmental protection and
Laser Marking a non-contact marking, energy conservation, as opposed to corrosion law to avoid chemical pollution; as opposed to mechanical marking, but also reduce noise pollution.

4. The application of laser tag
Applied to steel, non-ferrous metals, alloys and inorganic marking, and ceramics, diamond and silicon micro-processing of materials. At present, laser marking technology, including ABS keyboard, HDPE, PP, PET and PVC rigid containers, and containers, nylon and PBT components, HDPE button switches, PVC pipe, and so on the tag printing.
Laser Marking Machines categories and selection

1. According to the classification of laser
1) laser classification
Lasers are divided into solid-state laser (YAG YAG and YVO4 YVO4), gas lasers (He-Ne laser, CO2 laser) categories.
�� carbon dioxide (CO2) laser marker with CO2 gas as the activation of the media, launching a 10600nm infrared region of the light waves. Such lasers have two different forms.
a. Pulsed laser. Mask the use of methods in order to have a short pulse of laser energy or by tags. However, due to a number of tags need to block the view of the different objects, marked changes take a long time.
b. Continuous laser. Used in the form of light pen, a level only, do not ask for much technology and low cost, simple equipment, but exports of high-energy, high efficiency, is widely used in plastics laser tag printing.
�� YAG laser marker. Activation of the media is solid, fired a near infrared laser region of 1060nm light, continuous, two-light pen, by changing the output energy, can be of different intensity laser beam. Marking Technology has coking law (dark markings), the foam method (light-colored marker) and ablation (engraving marking), marking an excellent quality.
�� excimer laser marker. To launch a range of ultraviolet light (100 ~ 400nm), activated by the media, helium, argon, krypton, neon gas and chlorine, fluorine, bromine, iodine, such as halogen composed of a mixture constituted.

2) CO2 laser and solid YAG laser marker of distinction
�� the application of different materials. Because of their different wavelength, carbon dioxide laser marker can only be used for non-metallic materials marking; YAG solid laser marker for both non-metallic materials, marking, but also for marking metal materials.
�� used different supplies. CO2 laser marker is a major mixed-gas supplies and laser tube and the other is germanium lens wearing parts, the price is more expensive; YAG solid laser marker supplies is the main pumping light (the use of laser-pulse xenon lamps, laser-straight The use of krypton lamp), low price.
2. According to the laser output in the form of classification
Laser Marking machine based on laser output in different forms, can be divided into solid cover model, cover model of gas, mechanical scanning, scanning galvanometer, and other types.
3. Laser Marking Machine Selection
Laser Marking Machine Selection is based mainly on the need for printed material standard of products, production and decided to mark the area, following the principle of selection.
1) solid cover mode laser marker
Applicable to non-metallic materials, marking an area of 7mm cents in the cylinder, high-volume production of products such as electronic components and so on.
2) cover gas mode laser marker
Applicable to non-metallic materials, and cents marker in the area of 20mm cylinder, high-volume production of products such as electronic components, plastic bottles, food containers and alcoholic drinks and tobacco, and so on.
3) mechanical scanning laser marker
Apply to a single marker in the area of 80mm × 100mm, single-class production for the thousands of products.
4) galvanometer scanning laser marker
Apply to a single marker in the area of 300mm �� cylinder, single-class production for the tens of thousands of pieces.

Laser Marking System hardware and software

1. Laser Marking System hardware components
Laser Marking system, including laser marking machines, table and the three main external cooling system. Laser Marking machine control cabinet and by laser marking component of the first through the line of control systems connected; control cabinet, including laser power, RF frequency drive to control computers, monitors, main control panel and laser cooling system.
2. Laser Marking System Software
Own the copyright of the laser marking system software to be user-friendly and powerful graphics editing features, easy to learn, easy to use features, with video surveillance and heat-screen display functions, the system can be extended performance; icon can be, Font, flexible bitmap conversion, support for the bar code (128 yards, 39 yards), two-dimensional code (PDF417 code, ID MAIRIX yards), OCR-A software, bitmap and vector input and support, such as Auto CAD-A Graphics format; system errors and failures with alarm display.

Plastics Laser Marking

1. Plastic Laser Marking Technology
Plastic packaging is an important material, plastic products, trademarks, such as bar code numbers used to identify and mark the usual printing, labeling paste, hot contraction of the external processing methods, such as outer generation, or through the surface of the plastic products directly Processing machinery, such as embossing, engraving, marking the formation of punching and so on. The use of the laser marker in plastic tags are printed on the surface of a high-speed processing, plastics to maintain the inherent characteristics of the surface so that the text, numbers or icons and plastic products into a unified whole new type of marking technology. Plastics laser marking machine using a laser beam in plastic directly on the surface to generate marks, including marking, coding, labeling, characters, lines, numbers, colors and even do not need other processes.
2. Laser Marking Equipment and Materials
In order to get clear of laser tag, we must understand the following points:
1) Laser Marking Equipment
Different laser machine capable of launching different wavelengths of light, laser different from the ability to penetrate different; and adaptability of different laser tag on the quality and speed of tags will be affected.
Despite the existing plastics used to hit the target on the surface of laser light source, but sealed carbon dioxide laser is the most widely used with laser marking, followed by solid-state Nd: YAG laser diode and Nd: YAG laser. As a result, plastics marking the first choice should be carbon dioxide laser, if not required by contrast, or molten plastic over the option of Nd: YAG laser.
�� CO2 laser marker
Choice of laser marking machines, the cost is a key factor. A set of CO2 laser marker in the price of 25,000 to 35,000 U.S. dollars, and 1 tube diode or Nd: YAG laser marker in the price of 60,000 to 75,000 U.S. dollars between.
CO2 laser marker by etching the surface of plastic, waste clean-up evaporation, has been the contrast is the Indian standard, almost no color change. Bottled in the production line coding, marking speed is critical, particularly in the print Chinese characters when using carbon dioxide lasers in general.
The appropriateness of using carbon dioxide laser marking machine has hit the subject of plastic PVC, ABS and most of the polyester; mica-filled commercial resins such as PP, with carbon dioxide laser marker marking produced from cream of the standard gray and India. Although the carbon dioxide laser marking machine can achieve the output power of 200W, but the plastic used to hit the target power only 10 ~ 25W, to a maximum of 50W.
�� solid-state Nd: YAG laser marker
Nd: YAG laser marker is a popular marking equipment, and more generally for parts of China and India marked high-quality, such as electronic connectors, such as the hood. As the Nd: YAG laser marking machines have a shorter wavelength of the laser, high-energy, it can be a high-definition. But the heat will cause thermal plastic chemical reactions (such as foam) and color change.
2) product requirements and characteristics of the process
Marking prior to the selection of equipment, it is necessary to understand the production and marking requirements. For example, high contrast, India could not have interrupted the products, high-frequency laser is preferred. In addition, the devices need to pay attention to low-output power requirements of the suitability of speed.
3) plastic Adaptive laser
Different plastics have different laser energy absorption rate. Some plastic as easy to absorb energy and easy-to-marking; and some plastics do not absorb the laser can not be used to generate laser tag. Laser energy absorption rate is a function of wavelength, the laser intensity in the same role in different types of plastics will be a different quality of the mark. For example, some of the colored high-density polyethylene and polycarbonate used in YAG laser, not adding any additives can be an ideal mark; and carbon dioxide laser marker, it is necessary to not printed on special additives. In addition, the degradation of the plastic, cracks on the surface of the hollow, and so on, will lead to lower quality of the mark.
In addition to the use of laser marking additives to improve the printing of plastic, there are also dedicated to the subject of laser-printed plastic, such as laser printing dedicated to the subject of low-gloss black-formaldehyde acid copolymer, with anti-ultraviolet radiation.
4), laser tag and the role of the types of additives
Laser marking of plastics additives can change the spectral absorption characteristics, in particular, do not absorb the laser's special plastic, the proper use of laser marking additive for laser marking, and with quality comparable to the normal mark.
�� laser marking additive function
Laser marking additive main function is to absorb the laser energy, laser beam will be converted into heat, heat generated on the plastic, carbonation, evaporation and chemical reactions.
�� laser marking additive varieties
Additive products for different lasers are a number of varieties, such as for carbon dioxide laser subject of additives for different chemical properties of plastics, dark-colored background on the light-colored laser and light-colored markings on the dark background of the different laser tag Variety.
Another example is the Mark-lt laser tag is a pigment for plastics YAG laser marker additive designed for PE, PP, GPPS, HIPS, ABS, PET, PBT, Nylon, epoxy resin, ABS / PC, PC, such as plastic laser tag printing.