Researchers use blurry light to 3D print high-quality optical components

Canadian researchers have developed a new 3D printing method called Blur Tomography, which can quickly produce micro lenses with commercial grade optical quality. The new method can make designing and manufacturing various optical devices easier and faster.

Daniel Webber from the National Research Council of Canada stated, "We have intentionally added optical blurring to the beams used in this 3D printing method to manufacture precision optical components." "This enables the production of optically smooth surfaces."

In the highly influential research journal Optica of the Optica Publishing Group, these researchers demonstrated this new method for manufacturing millimeter level flat convex optical lenses with imaging performance similar to commercially available glass lenses. They also demonstrated that this method can produce usable optical components in just 30 minutes.

Webber stated, "Due to the economic viability of tomography 3D printers and the materials used, we expect this method to be highly valuable for economically efficient and fast prototyping of optical components." "In addition, the inherent free shape properties of tomography 3D printing allow optical designers to simplify designs by replacing multiple standard optical devices with printed optical devices with complex shapes."

Smooth edges
Fault volume additive manufacturing is a relatively new manufacturing method that uses projected light to cure photosensitive resins in specific areas. It allows the entire part to be printed at once without the need for any supporting structures. However, existing tomography methods cannot directly print lenses with imaging quality, as the pencil shaped beam used generates stripes, forming small ridges on the surface of the components. Although post-processing steps can be used to create smooth surfaces, these methods increase time and complexity, thereby eliminating the advantages of rapid prototyping related to fault printing.

"Due to the strict technical specifications required for functional lenses and the complex and time-consuming manufacturing process, the manufacturing cost of optical components is high," said Dr. Weber. "Fuzzy tomography can be used for low-cost free form design. As technology matures, it can quickly prototype new optical devices, which is useful for anyone from commercial manufacturers to garage inventors."

Create tiny lenses
To test the new method, researchers first created a simple planar convex lens and demonstrated that its imaging resolution can be comparable to commercial glass lenses with the same physical size. It also exhibits micrometer level shape errors, sub nanometer level surface roughness, and point spread functions close to glass lenses.

They also used fuzzy tomography technology to create a 3x3 microlens array and compared it with traditional tomography 3D printed arrays. They found that due to the high surface roughness, traditional printed arrays cannot be used to image business cards, but arrays printed by fuzzy tomography can be used. In addition, researchers also demonstrated the use of a spherical lens imprinted onto optical fibers, which previously could only be achieved using additive manufacturing technology called two-photon polymerization.

They are now committed to improving component accuracy by optimizing the optical patterning method and incorporating material parameters into the printing process. They also hope to introduce automation of printing time to make the system powerful enough for commercial use.
Webber stated, "Fault 3D printing is a rapidly maturing field with applications in many fields." "Here, we leverage the inherent advantages of this 3D printing method to manufacture millimeter level optical components. In this process, we have added a fast and low-cost alternative to optical manufacturing technology, which may have an impact on future technologies."

Source: Laser Net