Fiber Laser Engraver vs Diode Laser Engraver: What's the Difference?

1.2 Processable materials

The fiber laser is extremely versatile when it comes to material processing. It can effectively engrave and cut on a wide range of materials, including metals such as stainless steel, aluminum, and copper. It is also suitable for processing a number of non-metallic materials such as plastics (especially those with a high carbon content), and certain types of glass. For example, in the jewelry industry, fiber lasers are commonly used to engrave intricate designs on gold and silver jewelry. In the automotive industry, it can be used to mark serial numbers on steel or aluminum engine parts.

1.3 Pros

• High Precision: Fiber laser engraver is capable of extremely high precision, with spot sizes as small as microns. This makes it ideal for applications that require fine detail, such as micro-engraving on circuit boards or creating fine patterns on small parts.  
• High Efficiency: Fiber laser engraver has relatively high electro-optical conversion efficiencies, which means that fiber laser consumes less power while providing high power output compared to some other types of lasers. This not only reduces operating costs, but also allows for longer periods of continuous operation.
• High Beam Quality: Fiber laser engraver produces a high quality laser beam with a narrow divergence angle. This creates a more focused and intense beam, which facilitates deep laser engraving and cutting applications.
• Durable and Low Maintenance: Fiber laser engraver has fewer moving parts than some traditional laser systems. The fiber laser is also very robust, which makes it last longer and requires less maintenance. There is no need for frequent recalibration of components, and the system can operate reliably for thousands of hours. 

1.4 Cons

• Higher initial cost: Fiber laser engraver typically has a higher upfront cost than diode laser engraver. This is due to the fact that fiber laser engraver uses more complex technology and higher quality components. 
• Limited wavelength adjustment Fiber laser engraver typically operates at a specific laser wavelength, which for ytterbium doped fiber lasers is typically around 1064 nm. While this laser wavelength is suitable for many applications, it may not be optimal for all materials and there is limited flexibility in changing the laser wavelength to match the absorption properties of different materials.

2. Basic knowledge of diode laser

2.1 What is diode laser

Diode laser, also called semiconductor laser, is based on the principle of excited radiation in semiconductor materials. In a diode laser engraver, there is a p-n junction inside the semiconductor chip. When the p-n junction is energized, electrons and holes in the active region of the semiconductor combine. When they combine, photons are emitted. These photons are reflected back and forth between the two mirror-like end surfaces formed by cutting the semiconductor chip to form an optical resonance cavity. In this process, the light is continuously amplified and finally a laser beam is produced.

2.2 Processable Materials 

Diode laser engraver can also be used to mark on some metals, although its performance may not be as good as fiber laser engraver for deep laser engraving and cutting of metals. This is because the engraving range of the metal is very narrow and the cutting process is complicated. Engraving metal leaves only very shallow marks. Diode laser is the most commonly used to engrave wood, plywood, leather, opaque acrylic, coated metals and marble. In the packaging industry, diode laser is commonly used to mark product information on plastic containers. Diode laser engraver is also suitable for marking paper and cardboard, which is useful for applications such as bar code marking on shipping cartons.

2.3 Pros

• Low Cost: Diode laser engraver is usually more affordable than fiber laser engraver. This makes them an attractive option for small businesses or hobbyists with limited budgets who still want to venture into laser cutting and deep laser engraving.
  
• Laser Wavelength Versatility: Diode laser can produce lasers at a number of different laser wavelengths, ranging from visible to infrared wavelengths. This laser wavelength versatility makes it suitable for many different types of material processing, medical treatment, and scientific experimentation applications, offering the potential for a wide variety of uses.

2.4 Cons

• Lower power output: Diode laser engraver typically has a lower power output than fiber laser engraver. This limits its ability to deeply engrave or cut through thick materials. For example, it may have difficulty cutting thick sheet metal or achieving deep laser engraving on hard materials. 
• Lower Accuracy: Diode laser engraver typically does not have the same beam quality as fiber laser engraver. This results in larger spot sizes and less accurate engraving, making it less suitable for applications that require very fine detail. 
• Shorter lifespan: Although diode laser engraver has come a long way in terms of reliability, it typically has a shorter lifespan compared to fiber laser engraver. The semiconductor chips in diode laser engraver are more sensitive to temperature changes and electrical fluctuations, which can lead to performance degradation over time.

3. Difference between fiber laser and diode laser

3.1 Material Compatibility 

Material compatibility is a key consideration when selecting a laser engraver. The type of laser fundamentally determines the range of materials it can process.
Fiber laser engravers are specifically designed for laser engraving and cutting with metals. They also perform well with many plastics. However, fiber laser engravers are generally less suitable for wood, leather or other organic materials, whereas diode laser engravers perform better on these materials.

Diode laser engravers are mainly suitable for processing organic materials such as wood, leather, paper and some opaque acrylics. However, diode laser is usually not suitable for processing metal, glass or transparent materials.

3.2 Engraving precision

• Fiber Laser: Fiber laser engraver offers extremely high engraving accuracy and is capable of producing very fine detail. Its small spot size and high quality beam allow for intricate patterning and micro-engraving, which is critical in applications such as electronics manufacturing and jewelry design.
• Diode Laser: Compared to fiber laser engraver, diode laser enngraver offers relatively low engraving accuracy. Its larger spot size makes it difficult to achieve the same level of fine detail, and it is better suited for applications that require less precision, such as general product marking on packaging materials.

3.3 Applicable groups

• Fiber laser: With high precision, high power and wide material compatibility, fiber laser engraver is especially suitable for industrial manufacturing fields that require high precision marking of parts, such as aerospace parts marking, precision electronic components marking and so on. At the same time, for professional laser processing studio, need to undertake all kinds of complex, high-precision marking orders, fiber desktop laser marking machine is also a good choice, to ensure high quality and high efficiency to complete the task.
• Diode Laser: Diode laser engraver is more attractive to small businesses, hobbyists, and those just starting out in laser engraving and cutting. Its low cost, compact size and ease of use make it an excellent choice for customizing small objects, creating personalized gifts or producing small batches.

3.4 Power and speed

• Fiber Laser: It is available in a wide range of powers, from a few watts to several kilowatts. This wide range of power options allows them to be used for a variety of applications, from fine surface engraving to high-power cutting of thick materials. The speed of a laser is directly proportional to the optical power. The higher the power, the faster the speed. The fast cutting speed of the fiber laser is one of its significant advantages. Under the condition of the same laser power, the cutting speed of fiber laser is 15% faster compared to diode laser.
  
• Diode Laser: It typically has a lower power range, generally up to a few hundred watts. This lower power limit restricts its use to less demanding applications such as surface marking on thin materials. Diode laser, however, performs much better in terms of engraving speed. It can cut plywood up to 8 millimeters thick at a rate of 1-3 millimeters per second, which is quite fast.

4. Desktop laser marking machine recommendations

EM-Smart introduces the EM-Smart Dual: 20W Fiber + 20W Diode 2-in-1 Desktop Laser Engraver. Have no idea which one to choose? Then we can get both!

5. Conclusion

Both fiber laser engraver and diode laser engraver have their own unique characteristics and applications. Fiber laser engraver is preferred by those who need high precision, broad material compatibility and high power capabilities, making it ideal for industrial and mass manufacturing applications. Diode laser engraver, on the other hand, is better suited for smaller operations, hobbyists, or applications that primarily involve plastics and paper materials, thanks to its low cost, compact size, and ease of use. When choosing between fiber laser engraver and diode laser engraver, it's important to consider your specific needs, budget, and the types of materials and applications you'll be working with. By carefully evaluating these factors, you can choose the laser system that best meets your needs, and of course the combination of the two is a great addition to your desktop engraving process. Choose the EM-Smart Dual, to help you achieve your goals in laser engraving and cutting.