In the early days, the lasers used in industrial processing that we are familiar with are usually infrared lasers (wavelength of about 1um) and ultraviolet lasers (wavelength below 400nm).

In recent years, with the rapid development of my country's photovoltaic industry and lithium battery industry, green lasers (wavelength 510-560nm) have been continuously promoted and applied in the photovoltaic and lithium battery industries as a new popular laser, and have begun to be known in the industry. The commercialization of green lasers in the field of industrial processing has also made great progress.

01 Development of China's green laser market

The earliest companies in the world to deploy and promote green laser technology are German Trumpf and American IPG, which are also the most advanced companies in the world in green laser technology. German Trumpf and American IPG can obtain ultra-high power green light output of more than 3kW and 1kW respectively through solid-state disk laser technology and fiber laser technology.

With the development of green laser technology in my country, in recent years, a number of companies have emerged in my country that have mastered the research and development and production and manufacturing technology of green lasers, and domestic green lasers have gradually begun to enter the stage of industrial laser processing.

According to public market data, in the field of fiber lasers, Wuhan Ruike Fiber Laser Technology Co., Ltd., Shenzhen JPT Optoelectronics Co., Ltd., Shenzhen Gongda Laser Co., Ltd., Wuhan Anyang Laser Technology Co., Ltd. and Wuhan Guangzhi Technology Co., Ltd. all have public fiber green laser product introductions on their official websites.

In the field of solid lasers, Inno Laser Technology Co., Ltd., Suzhou Yinggu Laser Co., Ltd., Wuhan Huari Precision Laser Co., Ltd., Logan Laser Technology (Wuhan) Co., Ltd., etc. also have public solid green laser products.

According to the data collected by researchers from visits and surveys of green laser manufacturers and their upstream and downstream related companies, the market size of green lasers in my country is as follows: From 2018 to 2022, the annual shipments of domestic fiber green lasers are roughly 400-600 units, and the main products are pulsed fiber green lasers. The annual sales are roughly 100-140 million. Domestic enterprises have a low market share, and the market is mainly monopolized by foreign companies. In 2023, the shipments of domestic fiber green lasers will be around 800 units, and the main products will still be pulsed fiber green lasers, with annual sales of about 150 million. Among them, the domestic green light shipments will be around 500 units, and the sales of domestic green light will be 90 million-100 million, due to the price advantage of domestic green light products over foreign green light products. In 2023, although the shipments of domestic fiber green lasers will increase faster than in 2022, the overall annual sales will not increase significantly compared with 2022.

From 2019 to 2023, the annual shipment of solid green lasers in China is 300-500 units. Domestic solid green lasers are mainly low-power solid pulse green lasers, while foreign companies are mainly high-power solid continuous green lasers. The overall annual sales are around 100-140 million. The shipment proportion of domestic companies is relatively large, with annual shipments of about 200-300 units, but the unit price is relatively low. The sales of solid green lasers of domestic companies account for a small proportion of the total sales. Although foreign companies have fewer shipments, the unit price is higher. Therefore, the sales of solid green lasers of foreign companies account for a high proportion of the total sales.

With the continuous penetration of green lasers in the photovoltaic, lithium battery and semiconductor industries, as well as the continuous promotion and application in new fields such as 3D printing and aerospace, it is expected that in the next three years, the market size of domestic green lasers will continue to maintain an annual growth rate of 20-30%, and the domestic substitution development of green lasers will still have a broad market space.

Figure 1 China's green laser market size and forecast (unit: 100 million yuan)

02 Industrial applications of green lasers

Green lasers, due to their short wavelength working characteristics, have very important application requirements in the processing of highly reflective materials such as copper and aluminum, and are also indispensable tools in many cutting-edge scientific research fields. For example, green lasers are often used in hot industries such as solar cell scribing, doping, 3C electronics and semiconductor copper foil cutting and welding, lithium battery welding, wafer annealing and 3D printing.

1. Application of pulsed green fiber laser in copper foil cutting

Figure 2 Green laser cutting effect diagram

Pulse green laser is used to cut FDC lines. The minimum line width at the fuse position can be 150um. The cutting is smooth and the cutting efficiency is ≥1000mm/s. No base film is applied during cutting.

2. Application of pulsed green fiber lasers in photovoltaic doping

Figure 3 Effect of photovoltaic doping with green laser

The use of pulsed green laser for photovoltaic doping results in more uniform energy distribution and more stable pulse control.

3. Application of continuous green fiber laser in copper foil welding

Figure 4: Green laser welding effect on copper foil

Continuous green laser is used for copper welding. The welding is stable. The absorption rate of green light by copper is about 40%. There is no spatter during the welding process and the heat impact is small.

4. Application of continuous green fiber laser in lithium battery welding

Left: front welding effect, Right: back tearing effect)

Figure 5: Effect of green laser welding on lithium battery

Using continuous green laser to weld large cylindrical lithium batteries, the yield can reach over 95%.

5. Application of continuous green fiber laser in metal 3D printing

Figure 6 Effect of green laser metal 3D printing

Continuous green light lasers are used for 3D printing of high-reflective materials such as copper and titanium alloys, especially pure copper materials. Currently, the density of pure copper 3D printed samples can reach more than 99.5%, and the material parameters of the mechanical strength, thermal conductivity, and electrical conductivity of the printed samples are basically equivalent to those of the die-cast samples.

Source: Laser Manufacturing Network