A set of 33 droplets fabricated to create “OMU” using the optical vortex laser-induced printing technique. The novel technique precisely deposited the droplets with no satellite droplets produced. Credit: Ken-ichi Yuyama, Osaka Metropolitan University
Innovative technique enables cost- and time-saving microprinting technologies.
Will printed photographs ever match the precision of a mirror’s reflection? Even though the answer may still be no for a while, Osaka Metropolitan University scientists have made significant strides in precision printing with their innovative optical vortex laser-based technique that allows for the precise placement of minuscule droplets with micrometer-scale accuracy.
Current Challenges in Inkjet Printing
Inkjet technology is a well-known printing technique that emits microdroplets from a nozzle directly onto a surface. However, when the ink droplets are viscous, with high density, the nozzle often gets clogged, a concern that has prompted the search for more advanced technologies.
Breakthrough by Dr. Ken-ichi Yuyama’s Team
A research team led by Dr. Ken-ichi Yuyama, a lecturer at the Graduate School of Science of Osaka Metropolitan University, has succeeded in printing uniformly sized droplets, with a diameter of approximately 100 µm, using a liquid film of fluorescent ink—which is approximately 100 times more viscous than water. This was achieved by irradiating the film with an optical vortex, resulting in prints of exceptional positional accuracy at the micrometer scale.
“Using a special laser beam known as an optical vortex, we have achieved stable printing of high-viscosity liquids,” explained Dr. Yuyama. “This printing technique allows for the fabrication of microdroplet laser arrays and the micropatterning of conductive nanoinks, as well as bioinks for cell scaffolds, leading to the establishment of next-generation printed photonic or electronic devices.”
The research results were published recently in the journal ACS Photonics.
Reference: “Fabrication of an Array of Hemispherical Microlasers Using Optical Vortex Laser-Induced Forward Transfer” by Ken-ichi Yuyama, Haruki Kawaguchi, Rong Wei and Takashige Omatsu, 13 September 2023, ACS Photonics.
DOI: 10.1021/acsphotonics.3c01005
Funding: Japan Society for the Promotion of Science, Japan Science and Technology Agency
