InfraredTags, Invisible Barcodes Embedded in 3D Printed Objects

At MIT, a fourth-year doctoral student in the Department of Electrical Engineering and Computer Science has developed a method to “lock” information into a physical object. Using 3D printing and a camera that uses the infrared (IR) range, he can make parts that incorporate a label invisible to the naked eye containing data. Imagine, for example, a 3D printed router that, once scanned via this IR device, gives you directly the WiFi IDs and code of your home, or a box to adjust the temperature of your house directly from your phone. This method, called InfraredTags, could replace labels and barcodes, thanks to its ability to store a certain amount of data.

Mustafa Doga Dogan is an MIT student who started this new project in late 2020. He was looking to develop a way to make physical objects speak, like a photo or an audio file that includes different information such as time, date, title or artist. By combining 3D printing and infrared, he has come up with a clever way for any everyday object to transmit data, such as a barcode or a label, that is imperceptible to the naked eye.

Barcodes (QR codes or ArUco markers used for augmented reality) can be integrated into the geometry of the object to make them 3D printable as infrared labels (photo credits: MIT CSAIL)

Bar codes that are invisible to the naked eye

InfraredTags are hidden inside a 3D printed part and visible only through an infrared light. In concrete terms, a user will be able to integrate them during the modeling phase of the part and bring to life during the printing phase. The student’s technical challenge was the choice of material: the infrared light had to be able to pass through it. Dogan says it took him two months to find the right solution, in this case the right plastic filament. He turned to a German manufacturer that offers custom-made thermoplastics that are opaque to light but transparent to infrared light. However, he remained discreet on the company’s name.