Do not judge a book by its cover is the saying we know but with this solution by MIT researchers, you may still literally obey that but now you can judge a book and its content right from its cover.
In a post, they said they have developed a camera which can read through the pages of a book without even opening it.
“The system uses terahertz radiation, the band of electromagnetic radiation between microwaves and infrared light, which has several advantages over other types of waves that can penetrate surfaces, such as X-rays or sound waves. Terahertz radiation has been widely researched for use in security screening, because different chemicals absorb different frequencies of terahertz radiation to different degrees, yielding a distinctive frequency signature for each. By the same token, terahertz frequency profiles can distinguish between ink and blank paper, in a way that X-rays can’t.”
This radiation when passed through pages reacts different to chemicals which make up the pages in a book so using algorithms developed by the researchers, it can translate frequencies into readable words. This then means that the camera when placed on the cover, Terahertz receives back signals that perform better than X-rays in that frequency profiles can distinguish between ink and blank paper.
While this is not the first time we would be hearing about it, researchers in the past have employed this technique in security screening where you have materials like clothes and bags which are made of different chemical components.
This prototype is limited though as it stands today because the current algorithm can only differentiate between 20 pages with the ability to accurately read the first 9 pages. The energy of the signal past the first 9 is low thereby introducing noise which renders the frequency signature practically unreadable. In signal telecom terms, you can call this attribute attenuation whereby the quality of a signal becomes degraded over a distance after other multi path effects.
In light of this, the team at MIT (Massachusetts Institute of Technology) say they will continue to work on the system to make it read an entire book eventually.
You can watch the video attached for more on this from one of the researchers; Barmark Heshmat.
A practical application such a system would be in museums that house delicate ancient books which have generated public interest over time.
Team members on this project include; Barmak Heshmat, Ramesh Raskar, and Albert Redo Sanchez all MIT based while Justin Romberg and Alireza Aghasi are from Georgia Tech.