A Two-Laser 3D Printer Delivers Power, Cost Savings for High-Resolution Nano-Scale Objects
Adding a second, cheaper laser to a femtosecond-laser printing system can dramatically cut the power required, researchers find.
A team of researchers from Purdue University have come up with a new technique for 3D printing complex objects at a high resolution — delivering, they say, the potential for lower cost and higher precision than existing approaches.
"We combined a relatively low-cost laser emitting visible light with a femtosecond laser emitting infrared pulses to reduce the power requirement of the femtosecond laser [in our printer]," corresponding author Xianfan Xu explains of the team's work. "In this way, with a given femtosecond laser power, the printing throughput can be increased, leading to a lower cost for printing individual parts."
The 3D printing method targeted by the team is two-photon polymerization, which uses a mode-locking laser capable of pulsing at a rate measured in femtoseconds. It offers extremely high resolution, capable of printing nano-scale parts, but comes at a high cost in both the laser parts and the power they need. To solve this, the team's 3D printer uses two lasers: an 800nm femtosecond laser and a 532nm nanosecond laser.
Combining the two, the researchers say, allows the printer to operate with a 50 percent reduction in laser power — which, in turn, means a lower-cost femtosecond laser can be used. "In a conventional two-photon polymerization printing process, the femtosecond laser is first used to initiate a photochemical process that reduces the inhibition species in the material before printing starts," Xu explains. "We used a low-cost laser for this purpose instead."
In testing, the team's two-laser system proved capable of delivering high-accuracy printing for objects measured at the nano- and micro-scale. Better still, it proved the power savings: 3D structures could be printed using around 50 percent less power from the femtosecond laser, while 2D structures could be printed with 80 percent less power.
"This new printing approach could impact manufacturing technologies, influencing the development of devices across consumer electronics and healthcare sectors both now and in the future," Xu claims. "Our novel, 3D printing approach can be readily implemented in many existing femtosecond laser 3D printing systems."
The team's work has been published in the journal Optics Express under open-access terms.