How to choose between continuous and pulsed fiber lasers?

Fiber laser, with its simple structure, low cost, high electro-optical conversion efficiency, and good output effect, has been increasing in proportion in industrial lasers year by year. According to statistics, fiber lasers accounted for 52.7% of the industrial laser market in 2020.

According to the characteristics of the output beam, fiber lasers can be classified into two categories: continuous lasers and pulsed lasers. What are the technical differences between these two and what application scenarios are they suitable for? Here is a brief comparison of general applications.

As the name suggests, the laser output from a continuous fiber laser is continuous and the power is maintained at a fixed level, which is the rated power of the laser. The advantages of continuous fiber lasers during long-term stable operation.

The pulse laser is intermittent. Of course, this intermittent time is often very short, usually measured in milliseconds, microseconds, and even nanoseconds and picoseconds. Compared to continuous lasers, the strength of pulsed lasers is constantly changing, hence the concepts of "peaks" and "valleys".

Through pulse modulation, pulsed laser can be quickly released and reach maximum power at the peak position, but due to the presence of valleys, the average power is relatively low. It can be imagined that if the average power is the same, the peak power of pulsed laser can be much greater than that of continuous laser, achieving a higher energy density than continuous laser. This is reflected in metal processing, which has greater penetration ability. At the same time, it is also suitable for thermosensitive materials that cannot withstand sustained high heat, as well as some high reflectivity materials.

We can analyze the differences in application based on the output power characteristics of the two.

Continuous fiber lasers are typically suitable for:

·Large scale equipment processing, such as vehicle and ship machinery, cutting and processing of large steel plates, and other processing scenarios that are not sensitive to thermal effects but are more cost sensitive
·Used in the medical field for surgical cutting and coagulation, such as postoperative hemostasis
·Widely used in fiber optic communication systems for signal transmission and amplification, with high stability and low phase noise
·Used in the field of scientific research for applications such as spectral analysis, atomic physics experiments, and LiDAR, it can provide high-power and high beam quality laser output

Pulse fiber lasers are usually suitable for:

·Precision machining applications that cannot withstand strong thermal effects or brittle materials, such as processing electronic chips, ceramic glass, and medical biological parts
·The material has a high reflectivity and is prone to damage to the laser head itself due to reflection. For example, processing copper and aluminum materials
·Surface treatment or cleaning of the exterior of easily damaged substrates
·In processing scenarios that require high power and deep penetration in a short period of time, such as thick plate cutting, metal material drilling, etc,
·In situations where pulses are required as signal characteristics. For example, fiber optic communication and fiber optic sensors, etc
·Used in biomedical fields such as ophthalmic surgery, skin treatment, and tissue cutting, with high beam quality and modulation performance
·Manufacturing of metal parts with high precision and complex structures in 3D printing
·Advanced laser weapons, etc

Pulse fiber lasers and continuous fiber lasers have some differences in principle, technical characteristics, and applications, and are suitable for different situations. Pulse fiber lasers are suitable for applications that require high peak power and modulation performance, such as material processing and biomedical applications; Continuous fiber lasers are suitable for applications that require high stability and high beam quality, such as communication and scientific research. Choosing the appropriate type of fiber laser according to specific needs will help improve work efficiency and application quality.