New two-photon aggregation technology significantly reduces the cost of femtosecond laser 3D printing

Scientists at Purdue University in the United States have developed a new type of two-photon polymerization technology. This technology cleverly combines two lasers and utilizes 3D printing technology to print complex high-resolution 3D structures while reducing femtosecond laser power by 50%. It helps to reduce the cost of high-resolution 3D printing technology, thereby further expanding its application range. The relevant research paper was published in the latest issue of the journal Optics Letters.

High resolution 3D printing structure. Image source: Optical Express magazine

Two photon polymerization is an advanced additive manufacturing technology that relies on the precise 3D printing of materials using femtosecond lasers. Despite its outstanding performance in manufacturing high-resolution microstructures, the high cost has become a roadblock to its widespread application.

In view of this, the research team creatively combined relatively low-cost lasers that emit visible light with femtosecond lasers that emit infrared pulses, reducing femtosecond laser power by 50%. This innovative method effectively reduces the printing cost of individual parts.

The new method combines the single photon absorption of 532 nanometer nanosecond laser with the two-photon absorption method of 800 nanometer femtosecond laser. To achieve the optimal balance between two types of laser printing, the team also constructed a new mathematical model to gain a deeper understanding of the photochemical processes involved and accurately calculate the synergistic effects of two-photon and single photon excitation processes, ensuring that ideal printing results can still be achieved at lower femtosecond laser power.
The experimental results show that for 2D structures, the new method reduces the required power of femtosecond lasers by 80%; For 3D structures, it is reduced by about 50%.

The team stated that high-resolution 3D printing technology has broad application prospects, including but not limited to the manufacturing of 3D electronic devices, the development of micro robots in the biomedical field, and the construction of tissue engineering 3D structures or scaffolds.

Femtosecond laser 3D printing, in short, involves the occurrence of photochemical reactions in a very small volume to construct fine three-dimensional structures. This is a very cutting-edge technology in the field of modern additive manufacturing, but it has limitations in terms of printing speed and power budget. Now, the team has printed high-resolution structures while reducing power by half, overcoming cost barriers. The most valuable thing is that this new technology can easily integrate into existing femtosecond laser 3D printing systems, enabling faster application in various fields such as biomedical, micro robots, and micro optical devices.

Source: Yangtze River Delta Laser Alliance