What is Color Laser Marking?

When color marking is your goal the LP9000F series of fiber lasers are the best choice available in the market place for direct marking of metals , and also many plastics . Some of the major items required for fast, safe, and effective marking on metal are detailed just below. Worldwide Laser system engineers are experts at specification, design, building, and installation of laser systems and related automation or integration. Does your operation, or do your customers call for marking on metals? If so please review the details below and contact the experts at Worldwide Laser Service Corp for more details.

  • Control of laser waveforms
  • Control of hKz within laser waveforms
  • Ease of laser control to provide color marking appearance – which from our phone conversations seemed an important feature/function
  • Ease of laser control for annealing

Notes for Color Laser Marking

Specific note and comments:
Fundamentally, it is possible to do color mark with almost any laser source (or controllable heat source, for that matter). The difference is in the degree of control and the agility of the laser, also perhaps in the “softness” of the beam.

As we’ve discussed, Color Laser Marking is actually the controlled “growth” of a native metal oxide at the surface of the metal. Certain, more reactive, elements of the metal react with atmospheric oxygen to form a stable metal oxide. When laser marking the best option as source is the LP9000F series of fiber laser  largely because the laser provides the greatest flexibility in applying heat uncontrollably to create bright colors without the limitations to darker hues impacted by heat accumulation.

Capabilities of Color Laser Marking

Specifically, the LP9000F models offer the following capabilities, only some of which can be matched by a competitor model:

1. Range of pulse duration: In the LP9000-HA models, this ranges 10-200ns with 25 selectable waveform. In the LP9000F- EP models, this ranges 3-540ns with 40 selectable waveform.

2. Range of pulse repetition frequency:  All HS and EP models can operate from 1kHz to 1000kHz PRF. Additionally, each waveform of the laser can be operated from 1kHz to a maximum PRF, typically between 500kHz and MHz.
3. Of critical importance is the ability to run a specific waveform below its nominal frequency. For example, a 1mJ pulse creates 20W average power at kHz. The LP9000 laser models give you the flexibility to use that exact pulse shape and energy at lower PRF, for example, at 10kHz, the same waveform produces 10W average power, but each pulse still has the full energy, shape, peak power and duration as you would enjoy at PFR0 (20kHz, in this example). This feature allows you to dial in and separately optimize pulse duration, peak power, pulse energy and average power.

 

4. The vast range of pulse durations and pulse repetition frequencies offered also provide the user with expanded possibilities when selecting scanner parameters. For example, you can control local heat input using faster scanning speeds and more passes, but only if the laser operates well at higher PRF (to keep the pulse overlap constant as you increase linear scan speed).

5. Perhaps most importantly, you can change your laser parameters (waveform selection, PRF, power) essentially on the fly (more practically, vector-to-vector). While the competition has developed MOPA lasers to address our advantages, they did not do the same job implementing ease of control. As a result, most competitive offerings that provide more than one choice of pulse duration will require that you take the machine “down” and bring it up again in a different state to access the other pulse duration. By contrast, LP9000 does this within a few us simply by a change of the command inputs to your next marking vector.

6. LP9000 series is the only supplier offering a range of beam profiles (four, in fact) – ranging from single mode to a “soft” M2~3. For uniform color marking, there are advantages to using a higher mode beam to avoid the central “hotpots” of a near-single-minded beam (any M2 less than 1.6 will have this hotpots).

7. LP9000 Lasers also offers a range of four beam colllimators to give more flexibility for designing the spot size on the marking surface, and for providing greater independence in the selection of the scanner optics (for example, you may want a longer theta to gain greater working area, and our longer collimators allow you to retain the spot size you would have had with tighter optics).

8. Color Laser Marking is a very appealing application, but when taking it to production, becomes a significant multi-variable control challenge. Changes to material composition, thickness, heat-sinking, atmospheric temperature, air flow, laser temperature – these can all affect the stability of the recipe you develop for a specific color. The LP9000  laser give you direct control at the finest level of the essential laser parameters to allow you to quickly adjust to changes in your target or environment.