Laser holograms create 3D printed objects in seconds

How to create complex 3D printed objects in seconds instead of hours or days? A team of scientists and engineers led by researchers at Lawrence Livermore National Laboratory (LLNL) has developed a process for making complete objects in liquid resin cans in seconds using a hologram laser. This process is known as stereoscopic 3D printing, which overcomes many of the limitations of traditional additive manufacturing .

Additive manufacturing, also known as "3D printing," is expected to revolutionize prototyping and manufacturing, but it still has limitations. Traditional 3D printing works by layering printed objects. This process allows the prototype to be produced faster than machining, and it can produce very complex shapes in one unit rather than a few simpler units. However, such a process still takes several hours or even a few days to complete, and when printing an object, a temporary structure or the like may be required to support it until it is completed.

This latest technology was developed by LLNL in collaboration with researchers at the University of California at Berkeley, the University of Rochester and the Massachusetts Institute of Technology, and stereoprinting replaces layering while creating the entire object. This is achieved by using three overlapping lasers illuminated in a plastic resin-filled hologram-style transparent water tank. A single beam short-time illumination is not sufficient to cure the resin in a short time, but combining the three lasers can cause curing in about ten seconds. After the object is formed, excess resin is discharged to display the entire unit.

LLNL researcher Maxim Shusteff said: “In fact, you can complete 3D parts in one step, which really overcomes an important problem in additive manufacturing. We tried to print a 3D shape at the same time. The real purpose of this paper is to ask, 'we Is it possible to complete any 3D shape at once instead of layering the parts together? 'It turns out we can.'

Stereo printing is not only faster and more flexible, it does not require temporary support structures, and even provides more geometric flexibility. So far, it has been used to create squares, beams, planes, struts at arbitrary angles, lattices and complex curved objects.

However, the research team pointed out that there is currently a limit to the complexity of the shape, as continuous exposure can result in partial solidification of the unwanted liquid resin. LLNL engineer Chris Spadaccini said: "This is a possible demonstration of the next generation of additive manufacturing. Most 3D printing and additive manufacturing technologies are composed of one- or two-dimensional unit operations. This technology makes the manufacturing process a completely 3D Operation, which was not done before, if the potential impact on production volume can be huge."

The research results were published in the journal Science Progress.