There are different types of laser cutters that can be used for engraving, such as CO2 lasers, fiber lasers, or solid-state lasers. Each type has its own advantages and disadvantages depending on the material and the desired effect. However, one type of laser that stands out for its versatility and performance is the MOPA laser.

MOPA stands for master oscillator power amplifier. It is a configuration that consists of a master laser that generates a low-power seed beam and an optical amplifier that boosts the output power. The MOPA laser can be used for engraving metals and plastics with high quality and precision.

In this article, we will explain what a MOPA laser engraver is and how it works. We will also discuss the benefits of using a MOPA laser engraver over other types of lasers. Finally, we will give you some tips on how to choose a MOPA laser engraver for your needs.

How a MOPA Laser Engraver Works

A MOPA laser engraver consists of three main components: a master laser source, an optical amplifier, and an engraving head. The master laser source is usually a fiber laser that emits a low-power beam with a fixed wavelength. The optical amplifier is a device that amplifies the beam by passing it through a gain medium.

The gain medium can be either another fiber or a crystal. The optical amplifier can also modify the pulse duration and peak power of the beam by adjusting the pump power or using an optical modulator. The engraving head is the part that directs the beam onto the material surface with a focusing lens.

The principle behind MOPA is that by separating the generation and amplification stages of the beam, it is possible to achieve more flexibility and control over the beam parameters. For example, by changing the pulse duration, it is possible to vary the amount of heat transferred to the material.

Shorter pulses result in less heat damage and more contrast, while longer pulses result in more melting and deeper marks. By changing the peak power, it is possible to vary the intensity of the beam. Higher peak power results in faster engraving speed and more color options, while lower peak power results in finer details and less distortion.

The parameters that can be adjusted with a MOPA laser are:

  • Pulse duration: the time that the beam is on for each pulse. It can range from 4 to 200 nanoseconds.
  • Peak power: the maximum power of the beam during each pulse. It can range from 1 to 100 kilowatts.
  • Pulse frequency: the number of pulses per second. It can range from 1 to 4000 kilohertz.
  • Pulse shape: the waveform of the beam during each pulse. It can be either rectangular or Gaussian.

The Advantages of MOPA Laser Engraving

MOPA laser engraving has many advantages over other types of laser engraving, such as:

  • Higher flexibility and control over pulse duration and peak power, which allows for more customization and optimization of the engraving results.
  • Better quality and contrast of markings on metals and plastics, especially on dark or transparent materials, due to the shorter pulses and lower heat damage.
  • More possibilities for color marking on stainless steel and anodized aluminum, due to the higher peak power and the pulse shape modulation.
  • Less heat damage and corrosion on metal surfaces, due to the shorter pulses and lower heat affected zone.

The Applications of MOPA Laser Engraving

MOPA laser engraving can be used for a variety of applications, such as:

  • Industrial marking of components, tools, and products, such as barcodes, QR codes, logos, serial numbers, or data matrix codes. MOPA laser engraving can provide high-speed, high-quality, and durable markings that can withstand harsh environments and comply with industry standards.
  • Decorative engraving of jewelry, gifts, and artworks, such as names, initials, dates, messages, patterns, or images. MOPA laser engraving can create beautiful and personalized designs that can enhance the appearance and value of the items.
  • Security marking of identification cards, passports, and labels, such as holograms, microtext, or hidden marks. MOPA laser engraving can create complex and unique features that can prevent counterfeiting and tampering.
  • Medical marking of implants, instruments, and devices, such as codes, symbols, or logos. MOPA laser engraving can provide sterile, biocompatible, and traceable markings that can ensure safety and quality.

How to Choose a MOPA Laser Engraver

If you are interested in buying a MOPA laser engraver for your business or hobby, there are some factors that you should consider before making a decision. Some of these factors are:

  • The power output and wavelength of the laser source. The power output determines the speed and depth of the engraving, while the wavelength determines the compatibility with different materials. For example, a 20-watt MOPA laser with a 1064-nanometer wavelength can engrave most metals and plastics with good quality and speed.
  • The size and speed of the engraving area and head. The size of the engraving area determines the maximum dimensions of the material that can be engraved, while the speed of the engraving head determines the productivity and efficiency of the process. For example, a MOPA laser engraver with a 200 x 200 millimeter engraving area and a 7000 millimeter per second engraving speed can handle most common applications with ease.
  • The software and features of the engraving machine. The software is the interface that allows you to control and customize the engraving parameters and designs. The features are the additional functions that enhance the performance and convenience of the machine. For example, a MOPA laser engraver with a user-friendly software that supports multiple formats and languages and features such as autofocus, red dot pointer, rotary axis, or air cooling can make your work easier and more enjoyable.
  • The price and warranty of the product and service. The price is the amount of money that you have to pay for the machine and its accessories. The warranty is the guarantee that covers any defects or damages that may occur during a certain period of time. For example, a MOPA laser engraver with a reasonable price that includes delivery, installation, training, and maintenance and a warranty that covers at least one year of service can give you peace of mind and value for money.

Conclusion

MOPA laser engraver is a type of laser engraver that uses a master oscillator power amplifier configuration to generate a beam with adjustable pulse duration and peak power. This allows for more flexibility and control over the engraving results, such as quality, contrast, color, depth, and speed. MOPA laser engraver can be used for various applications, such as industrial marking, decorative engraving, security marking, or medical marking. MOPA laser engraver can engrave metals and plastics with high precision and performance.

If you are looking for a MOPA laser engraver for your needs, you should consider the following factors: the power output and wavelength of the laser source, the size and speed of the engraving area and head, the software and features of the engraving machine, and the price and warranty of the product and service. You should also compare the different models and brands of MOPA laser engravers available in the market and choose the one that suits your budget and expectations.

FAQs

What is the difference between MOPA laser and fiber laser?

Fiber laser is a type of solid-state laser that uses a fiber as the gain medium. MOPA laser is a configuration that uses a fiber laser as the master oscillator and an optical amplifier as the power amplifier.

What are the benefits of using MOPA laser over fiber laser?

MOPA laser has more flexibility and control over the pulse duration and peak power of the beam, which results in better quality and contrast of markings on metals and plastics, more possibilities for color marking on stainless steel and anodized aluminum, and less heat damage and corrosion on metal surfaces.

What are the disadvantages of using MOPA laser over fiber laser?

MOPA laser is more expensive and complex than fiber laser. It also requires more maintenance and calibration due to the optical amplifier.

What are the best materials for MOPA laser engraving?

MOPA laser can engrave most metals and plastics with good results. Some examples are stainless steel, titanium, aluminum, brass, copper, iron, gold, silver, chrome, nickel, zinc.

Reference: https://www.troteclaser.com/en/laser-machines/laser-accessories/mopa-laser

Author

  • Ben Carver

    Ben is a dedicated laser cutting and engraving specialist based in the vibrant city of Atlanta, GA. He has contributed to The Independent, Business Insider, Yahoo, Entrepreneur, and Business Insider. He has spent the last 7 years staying at the forefront of laser engraving industry. He has worked with various companies and people to create innovative and cutting-edge designs. Ben is passionate about the versatility and precision of laser cutting and enjoys exploring new techniques and materials to push the boundaries of what is possible.