Plastic-layer thickness used to form unique IDs for 3D-printed objects
As is the case with items that are manufactured in more traditional manners, it's certainly possible for 3D-printed products to be counterfeited. A new system could help identify such bogus goods, by printing a unique code right into objects.
Known as Fused Deposition Modelling, the most common form of 3D printing involves using a nozzle to lay down successive thin layers of molten plastic. That plastic then hardens to form the finished product, with the edges of the layers still visible on its exterior surfaces.
And ordinarily, all of those layers are of an equal thickness.
A team from Japan's Nara Institute of Science and Technology (NAIST), however, has developed a system in which a series of adjacent layers (in a certain part of the object) are deposited in specific subtly-different thicknesses. This is achieved by varying the plastic flow out of the 3D printer's nozzle, and it doesn't negatively affect the overall shape or structure of the item – after all, the same amount of plastic still ends up being deposited in the same places.
The result is a layer-thickness pattern that's almost like a barcode, which is unique to that product. And as long as it's on a flat part of the item, that code can be read simply by placing the object on a conventional document scanner, which images and analyzes the thickness of the layers in the relevant region.
In order to further thwart counterfeiters, the pattern can be applied to multiple parts of the item. This means that even if it's scraped, cut or melted off of one area, it will still be visible on others.
Along with embedding product-specific anti-counterfeiting IDs, it is thought that the technology could also be used to include information such as links to web services, or the identity of the specific printer that was used to manufacture a certain batch of items.
A paper on the research was recently published in the journal IEEE Transactions on Multimedia.