A group of innovative researchers discovered a way to reduce 3d printing costs and improve performance via a new two-laser printing method. The Purdue University team published a detailed study of their findings in the scientific journal Optics Express. The study delves into the details of an advanced dual-color laser additive manufacturing technique that enhances the current Two-photon polymerization model. Here’s everything you need to know.
Today’s Additive Manufacturing Processes
To fully understand the significance of this study, it’s wise to take a quick glimpse into the evolution of the additive manufacturing process. The concept of 3d printing has been an exciting journey that resembles science fiction at times. These devices have gone from comic books to one of the most popular, and often the only way to create certain devices.
Material Extrusion
The first 3d printers used a method called material extrusion. A heated nozzle would have a long spool of thermoplastic filament fed through it. The filament would be warmed until malleable and then applied in layers to form the required shape. This 3D printer style is the most affordable and widely used option today.
Powder Bed
Powder bed 3D printers are used for creating metal and ceramic items. This method of 3D printing integrates a powered bed and an inkjet printer that sprays a binding material. This material creates the item layer by layer and is capable of intricate 3D designs. Recent developments in this approach have made printing multiple materials and even electronics possible.
Fused Deposition
Fused deposition uses a thermoplastic filament that is deposited using material extrusion methods. From there, lasers are used to mold and lock the shape of the item in place with great precision. Notably, the use of lasers in the additive manufacturing sector is common, with the first use of Stereolithography (SLA) occurring in 1984.
Two-photon Polymerization (TPP)
Today a Two-photon polymerization (TPP) method is the most commonly used for micron-scale industrial prints. This method relies on dual femtosecond lasers which can mold, cure, and solidify purpose-built composites. It provides high accuracy and is a proven method for creating microstructures and other tiny detailed devices that would be impossible using other methods.
Issues with this Approach
Multiple issues with the TPP method led researchers to explore alternatives. For one, femtosecond lasers are very expensive, sensitive, and require high precision. The slightest alteration can leave these devices requiring heavy maintenance.
Researchers
Recognizing these inefficiencies in this setup, researchers led by Purdue University engineer Xianfan Xu have put together a new multi-layered approach that promises to reduce costs. To accomplish this task, the team needed to overcome a variety of obstacles ranging from laser interference to tuning. Here’s how they were able to beat the odds and create a completely new manufacturing process that has the potential to upend the market.
Two-Laser Study
The study “Two-color 3D printing for reduction in femtosecond laser printing power” examines the use of a lower-powered laser to handle some of the tasks that previously required dual femtosecond units. To accomplish this task, the team created a custom-built two-photon lithography setup. This arrangement includes a secondary laser path to the print plane, enabling researchers to gather valuable real-time data on the laser’s effects.
Step 1 – Prep the Material
The first step researchers took was to put the material through a photochemical process. This process helps to lower the inhibition species in the material, making it more malleable to the lasers used for the molding and curing process. As such, this extra step enabled researchers to eliminate the use of dual femtosecond lasers.
Low-Cost Laser
The new process enabled researchers to leverage a less expensive option for the first laser interactions. The team eliminated a femtosecond unit and replaced it with a visible light option that worked in collaboration with the high-powered device. This low-cost laser was tuned to complement the femtosecond laser without adding interference.
Femtosecond Laser
The femtosecond laser chosen for the test was a 532 nm nanosecond (ns) pulsed fiber laser from MPB Communications Inc. The device provides high tunability, enabling the team to try different repetition rates. The team eventually settled on an 80 MHz repetition rate at a 1.2 ns pulse width.
Two-Laser Mirrors
The pulses were further concentrated via a Nikon, NA = 1.49 100X oil immersion objective lens. This approach integrated highly dispersive ultrafast mirrors from Edmund Optics as a way to initiate precompensation dispersion. Additionally, a helium-neon (HeNe) laser was used to ensure accuracy. Specifically, this beam ensured the laser path was repeatable.
A Balancing Act with Two-Laser
The precision needed to create this new manufacturing process required engineers to create a new mathematical model. This model made it possible to map photopolymerization reactions across states. In the past, separate models were used to calculate the excited state and subsequent polymerization kinetics of the laser.
The updated model enabled researchers to accurately measure the combined effect of two-photon and single-photon excitation processes in real-time. This capability allowed the team to determine the lowest power consumption requirements for the femtosecond laser to accomplish its tasks without losing performance.
Two-Laser Testing
The researchers then went to work testing their creation on multiple designs. These various 2d and 3d structures were chosen due to their complexity and size. The team wanted to ensure their device could be created on a micron scale. As such, the first items they printed were detailed woodpiles that measured 25 × 25 × 10 μm.
Source – Optica
The team didn’t stop at the woodpiles. They also printed a microscopic buckyball, a chiral structure, and a trefoil knot. These shapes were chosen because they allowed the team to demonstrate multiple aspects of their research. Here’s what the test results say about their efforts.
Results
The test results showed considerable improvement in the unit. The device was able to print all units using 50% less power. The power reduction was accomplished in multiple ways. First, the researchers reduced the femtosecond lasers from an 800 nm device down to a 530 nm laser. This change added efficiency without cutting performance using the new method.
Additionally, the new process was able to produce similar results to the industry standard using less material and time. Specifically, the single-photon absorption from a visible wavelength laser reduced inhibitor concentration while providing comparable results.
Easy Integration
One of the biggest advantages of this study is that the new method can easily be integrated into current methods for minimal costs. This approach would help to reduce costs by eliminating the need for manufacturers to purchase new devices. Instead, their current setups can be retrofitted to use the new lower-cost method.
Two-Laser Applications
There are several immediate applications for this technology. Additive manufacturing is more popular than ever, and any way to reduce costs and improve performance is sure to receive support from the sector. Here are a few other applications for this tech.
Micro Electronics/Robotics
The miniature scale at which these devices can print makes them ideal for use in microelectronics and robotics. These units are notoriously difficult to build and have become a vital part of many industries. As such, this new manufacturing process would make it easier to create and prototype new structures for use in these devices.
Biomedics
Healthcare is another field where these microstructures and devices are found in use. Tiny scaffolds and structures are now used for engineering tissue and other bio-robotic devices. These units are helping people to recover from injuries faster and enjoy an improved quality of life.
Companies That Could Benefit from This Research Today
Many different firms could benefit from this research in the coming years. From biomedics to military and industrial use, micro additive manufacturing systems could see improved performance using the new multi-color laser printing method. Here are a few companies that could integrate this tech immediately and see results.
1. Medtronic 
US-based Medtronic is a global leader in the medical device field. The manufacturer was founded in 1949 as a medical repair facility. Today, the company holds multiple patents in medical technology and is one of the most recognized names in the industry.
Medtronic was a pioneer in the pacemaker industry and was one of the first to patent an implantable device. Since that time, it has remained a dominant force in the market, continuing to introduce new tech to better patients’ lives. The integration of a two-color laser printing method would improve their offerings significantly by allowing them to reduce the size of their devices.
Medtronic is one of the most successful medical device manufacturers in the world. In 2024, the firm secured $32B in revenue. Today, Its continued innovations and positioning make it an ideal addition to any portfolio.
2. Abbott Laboratories 
Abbott Laboratories has been around since 1888. It was founded in Illinois and quickly grew into one of the most recognizable names in the industry. Abbott Laboratories offers a selection of products, including pharmaceutical drugs, medical devices, dietary supplements, and nutritional supplements.
Abbott Laboratories has products that span multiple sectors of the medical industry. Specifically, they are recognized for their cardiovascular, diagnostics, diabetes, and neuromodulation offerings. Additionally, they operate some very popular subsidiaries including Pedialyte and Similac, leading baby formula producers.
Stock performance has remained on the up for Abbott Laboratories. The company’s combination of medical devices and nutritional offerings makes it a strong “hold” for any trader. The future looks bright for this firm which now plays a pivotal role in providing heart healthcare devices globally.
Future
Few industries have seen such innovation as the additive manufacturing market. This latest development will help to drive the use of these devices in miniature robotics and electronic devices such as wearables. In the future, microwearables and implantable medical devices will take a more centered role within the industry. Here are some other recent 3d printing advancements that could help propel adoption.
Space Printers
There have been recent developments in the space printing sector. These units differ from human counterparts in that they need to be able to print layers without the help of gravity. This task is not easy to accomplish as all the current methods require a layering approach.
Researchers were able to overcome these issues using some intricate mathematics and by enclosing the device. The enclosure serves multiple purposes including protecting the astronauts from deadly fumes or other mishaps that could jeopardize the highly sensitive atmosphere of a spacecraft.
AI Printers
AI 3d printers are becoming more common. The integration of advanced AI algorithms is having a resounding effect on nearly every tech industry. In the future, you will be able to request 3D prints simply by chat or voice.
AI continues to provide a streamlined way for people to overcome technical barriers. As such, it’s seen by many as one of the most important developments in the market. In the future, AI 3d printing stations and other services will be commonplace. For now, this tech continues to streamline interactions and remove technical roadblocks for new users.
Self Repairing Robots
Another sci-fi scenario that is a reality is self-repairing robots. It didn’t take long for researchers to create a 3D printer that could print all of the parts it needed to operate. Now, this same concept is to be applied to robotics. Self-healing and repairing robots will help society function in the future, taking up hard tasks and jobs that the average person wouldn’t be able to handle.
Two-Color Laser Printing is a Major Upgrade
The work these researchers put forth will have a resounding effect on the 3d printing industry moving forward. You can expect to see more micro-robotics and electronic devices leveraging this method as a means to cut costs and improve results. As such, this team has laid the foundation for a new era in micro-additive manufacturing.
Learn about other cool additive manufacturing projects now.
