There are numerous types of laser equipment available in the market today. Each type of laser is designed to meet specific requirements for different materials.
Hence, it is not possible to determine which laser is the best solution as no single laser technology can meet all requirements. This will remain unchanged even with advancements in technology in the future. Just like individuals have their areas of expertise, lasers too have their own strengths and excel in specific fields.
Currently, the domestic laser market makes use of several types of lasers such as fiber lasers, CO2 lasers, semiconductor lasers, and UV lasers. These lasers are utilized in various industries and applications.
Fiber laser
Fiber lasers use glass fibers doped with rare earth elements as the gain medium to generate various wavelengths.
One of the unique features of fiber lasers compared to other solid-state lasers is their “high amplification resonator.” This results in most of the resonator power being transmitted through the output mirror, leading to high stress levels on the resonator system.
The small diameter of the fiber also results in a high power density within the fiber, which can be dangerous.
Today, fiber lasers are a common piece of laser equipment due to their relatively mature technology, affordability, and low operating costs.
Solid-state laser
Solid-state lasers generate laser beams using gain media, typically neodymium or ytterbium-doped neodymium-doped yttrium aluminum garnet crystals (YAG).
The YAG laser emits a beam wavelength of around 1μm, which falls within the near infrared band.
Due to their versatility in beam transmission and ease of integration into other systems, solid-state lasers are widely used in 3D manufacturing processes such as cutting, welding, and electroplating.
While demand for CO2 lasers is expected to increase in the future, solid-state lasers are poised to increasingly replace CO2 lasers, even in traditional CO2 laser processing fields like 2D cutting.
CO2 laser
The CO2 laser is the most powerful continuous wave laser available.
One of the key differences between the CO2 laser and solid-state laser is its wavelength, which ranges from 9.4 to 10.6 μm.
This laser is significant because of its varying laser absorptivity in both metallic and non-metallic materials.
The power range of CO2 lasers varies from less than 10 watts to over 20,000 watts, and they can be operated in either continuous wave mode or pulse conditions.
With a sufficient resonator length, CO2 lasers can achieve excellent beam quality through proper laser design. Their efficiency falls between that of round rod lasers and disk or fiber lasers.
Ultraviolet laser
The UV laser is primarily used in cutting-edge research, development, and industrial manufacturing equipment.
It is also widely utilized in biotechnology, medical equipment, and disinfection equipment that require UV radiation.
The DPSS UV laser based on Nd: YAG / Nd: YVO4 crystal is an excellent choice for micromachining systems and is widely used in printed circuit boards and consumer electronics.
Currently, the UV laser is highly suitable for the integrated development of scientific research, industry, and original equipment manufacturer (OEM) systems.
Semiconductor laser
Semiconductor lasers, also known as laser diodes, are lasers that utilize semiconductor materials as their working material. The process of each type of laser is unique due to differences in material structure. Common working substances include gallium arsenide (GaAs), cadmium sulfide (CDS), indium phosphide (INP), and zinc sulfide (ZnS). There are three methods of excitation: electric injection, electron beam excitation, and optical pumping.
Semiconductor laser devices can be classified into various categories including homogeneous junction, single heterojunction, and double heterojunction. Homojunction and single heterojunction lasers are typically pulse devices at room temperature, whereas double heterojunction lasers can operate continuously at room temperature.
In industrial laser equipment, semiconductor lasers are generally 1064nm, 532nm, and 355nm, with power ranging from a few watts to thousands of watts. 1064nm is typically used in applications such as SMT template cutting, automobile sheet metal cutting, and laser marking machines. 532nm is suitable for ceramics processing, glass processing, and other fields, while 355nm UV lasers are ideal for film windowing, FPC cutting, silicon wafer cutting, scribing, high-frequency microwave circuit board processing, and other applications.
