In a plastic bag, she carries an object wrapped in a moist towel.

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Printing in 3D involves sending a design file to a printer that then forms a solid version of that object by slowly building it up in layers of plastic.

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They said that by using stereolithography, their printer could offer "layer thicknesses and feature sizes that are worlds ahead of what is possible with" the existing technique used by budget printers, which melt plastic and squeeze it through a nozzle to build up each layer of an object.

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The extruders, naturally, melt the plastic down, while the heat from the platform plays a role in keeping the object in place as it's printed -- or, more precisely, the lattice work foundation that object is built on top of.

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The plastic must also be flat and smooth for the reading to be accurate, and the object must be brought to the machine (which is not very portable) for analysis, which takes yet more time.

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