Scientists have created “acoustic holograms” that can assemble matter into 3D objects using only sound. The technology works with different types of particles and even living cells, enabling a new kind of fast, contactless 3D printing of him.
Sound exists as pressure waves that pass through media such as air or water. These waves can exert pressure on the surface they impinge on, but the force is so small that we usually only notice it acting on the eardrum. to levitate small objects, create complex soundscapes, and add tactile sensations to visible holograms.
For the new study, Max Planck and scientists at the University of Heidelberg explored new uses for ultrasound. They used 3D printed plates specifically designed to generate a specific sound field. By combining these plates with different designs, you can create an acoustic hologram of her specific 3D shape.
It’s like an invisible type. When this ultrasound hologram is applied to particles suspended in a liquid, pressure waves are applied to different areas with varying intensities until the particles coalesce into the exact desired 3D shape. In tests, the team was able to use materials such as glass beads, hydrogels, and even living cells to create shapes such as doves, figure eights, and spirals.
This technique has several potential advantages. It works in a single step, making it faster and more efficient than traditional 3D printing, which builds objects layer by layer. And because the particles don’t need to be physically touched, they’re friendly to living cells, making them ideal for creating tissues and organs.
“This could be very useful for bioprinting,” said study author Peer Fischer. “The cells used there are particularly sensitive to the environment during the process.”
Future work, the team says, could explore ways to improve the technique, such as using more hologram plates, higher frequency ultrasound, and different materials.
A study was published in a journal scientific progress.
Source: Max Planck Institute
