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Laser Marking Systems-Technology Comparison |
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RMI's YVO4 vs. YAG, CO2 and Fiber Pulsed Lasers
While Nd:YAG lasers have had notable successes over the last few years, Nd:YVO4 (Vanadate) lasers have emerged with many impressive capabilities that often yield better results than Nd:YAG systems.
| Laser Marking Systems Comparison |
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Nd:YVO4 (RMI) |
Diode-pumped Nd:YAG |
Fiber |
CO2 |
| Wavelength (nm) |
1064 |
1064 |
1030 to 1050 |
10600 |
| Power (W) |
5 to 15 |
3 to 50+ |
3 to 50+ |
30-100 |
| High-PRF* applications |
Excellent |
Good |
Excellent |
N/A |
| Beam quality |
Good |
Fair to Good |
Good |
Poor |
| Beam spot size (microns) |
30 |
30 to 100 |
30 |
800 |
| Pulse peak power |
Good-Excellent |
Excellent |
Fair-Good |
Poor-Fair |
| Mark quality (Metals/Plastics) |
Excellent |
Good-Excellent |
Good-Excellent |
Poor |
| Equipment size efficiency |
Excellent |
Excellent |
Excellent |
Good |
| Cooling efficiency |
Excellent |
Good |
Excellent |
Good |
| Operating cost effectiveness |
Excellent |
Excellent |
Excellent |
Good |
| Maintenance Intervals (hours) |
30,000+ |
10,000 |
30,000+ |
Up to 500 |
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| *Pulse repetition frequency |
Nd:YVO4 vs. Nd:YAG
Compact Size
• Nd:YVO4 crystals have five times the absorption coefficient and two to ten times the stimulated emission cross-section at the lasing wavelength than Nd:YAG crystals.
• Nd:YVO4 crystals have a broader absorption bandwidth at the pump wavelength when compared to Nd:YAG crystals.
• In a diode-pumped solid state laser, the energy produced by the laser diode is used by the crystal to produce laser light with the excess being stored as heat. In the absence of an adequate cooling system, this heat will build up and damage the crystal. An Nd:YVO4 crystal is twice as efficient at energy conversion as an Nd:YAG crystal, so far less heat is produced at the same power output.
Therefore, Nd:YVO4 laser marking systems require smaller, less expensive cooling systems than Nd:YAG systems. This allows for a more compact design and a smaller footprint than comparable Nd:YAG systems, making them more portable and easier to integrate.
Highest Resolution
• When using the same size crystal, Nd:YVO4 systems are capable of producing a smaller spot size, resulting in a higher resolution mark than that produced by Nd:YAG systems.
Longer Diode Life
• In an Nd:YVO4 laser marker, the laser diode operates at a lower power level than in Nd:YAG systems while maintaining the same power output. This extends the life of the laser diode.
Nd:YVO4 vs. Fiber Laser
Disadvantages of fiber lasers compared to Nd:YVO4
• The lower peak power of the pulse means fiber lasers don’t mark on every material, especially harder metals and denser materials. Annealing or melting may occur, but not marking or engraving.
• Fiber lasers are susceptible to damage by reflected light, especially with highly-reflective surfaces. Increasing the power aggravates the problem and can damage the laser.
• If too much light is reflected back into a fiber laser, the fiber amplifier can instantly be damaged, resulting in the destruction of the pumping source itself.
• The design of fiber lasers is not based upon the use of modular components, as is the case with Nd:YVO4 lasers. Therefore, repairing fiber lasers can be quite expensive.
Advantages of fiber lasers
• Performance is similar to that of Nd:YVO4 lasers on many materials
• They require no alignment, so they can be easier to maintain
CO2 vs. YAG, Fiber and Nd:YVO4
Disdvantages of CO2 lasers
•The 1064nm wavelength produced by Nd:YVO4 , Fiber and Nd:YAG lasers is absorbed by most metals to create a clear mark, whereas the 10.6 micron wavelength produced by CO2 lasers is reflected by most metals and does not create a visible mark without the use of additive chemicals and sprays.
Advantages of CO2 lasers
• CO2 lasers, because of the large amounts of heat they generate and their high power output are ideally suited to cutting and welding.
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