A team of five researchers from MIT and Georgia Tech have developed a camera that uses terahertz radiation to read the content of a closed book.
Terahertz radiation is one of the bands of electromagnetic radiation that falls between microwaves and infrared light. One of its properties is that it can penetrate surfaces. Additionally, different materials absorb different terahertz radiation at various frequencies.
New MIT camera works on terahertz radiation
MIT researchers have created a camera that emits terahertz radiation and then measures the time it gets a reflection and for which frequencies.
This radiation passes through the book’s cover and is reflected and absorbed in pages, the air gaps between them, and the chemicals used to print the letters.
By knowing how terahertz radiation waves interact with air, researchers are able to distinguish between different pages of the book. The same for the letters’ chemicals.
Special software is needed to interpret the book scans
Researchers also created novel software that can read imagery created by the camera and distinguish between overlaid letters, in case the camera reads and jumbles together characters from different pages.
“It’s actually kind of scary,” Barmak Heshmat, one of the researchers, says of this software. “A lot of websites have these letter certifications [captchas] to make sure you’re not a robot, and this algorithm can get through a lot of them.”
Currently, researchers said their camera can only scan books as deep as 20 pages, and read the letters on only the first nine.
Nevertheless, MIT says that The Metropolitan Museum in New York showed genuine interest in their discovery. Their invention could be used to read old manuscripts that Museum employees say are so frail, they’re afraid to touch.
Researchers also expect their camera to become more potent as other scientists explore terahertz technology as well.
