Making the invisible visible – sounds like something out of Harry Potter. And one day, you'll be able to read all of the Potter books, or any other book for that matter, without cracking the spine. But, in this case, it's not a wizard who's doing the magic. It's a team of researchers at the Massachusetts Institute of Technology (MIT) and Georgia Tech, who have developed a system that can read the pages of books without opening the cover.
No, this isn't just the latest in e-reader technology. In fact, no less than the Metropolitan Museum in New York has expressed an interest in the system, which would allow researchers there to read antique and fragile books that are too delicate to be handled, said study author and MIT research scientist Barmak Heshmat in a news report.
Take a look at the video to see how the magic works:
The technology of seeing through books involves terahertz radiation, the band of electromagnetic radiation between microwaves and infrared light. These waves can penetrate surfaces and yield a different frequency for each chemical the waves encounter. Unlike X-rays, terahertz frequency profiles can tell the difference between ink and paper. There are tiny air pockets between the pages of a book and the researchers use a terahertz camera to emit radiation through those pockets. The camera's sensor detects the radiation reflections and researchers use the time of arrival back to the sensor to gauge the distance to each page in a book.
Stay with me. The payoff is coming. The info about page distance uses an algorithm to extract information about the chemical properties – ink or paper – of the reflecting surfaces, and to identify the letters on the pages in the correct page order and letter sequence.
As of now, researchers can only read the top nine pages of a book or stack of paper. But, they say, terahertz imaging is a new kind of magic – er, technology – and researchers are working to improve the accuracy of detectors and the power of the radiation sources, in order to read books from beginning to end.
Maybe these MIT/Georgia Tech blokes are really wizards in disguise.