Reading Through Closed Books

MIT and Georgia Tech researchers have found a way to read through closed books. Their imaging system was able to identify text on the first nine pages of stacked paper. It uses terahertz radiation that can distinguish ink from blank paper. One algorithm is used to acquire images from individual sheets of paper.

A second algorithm is used to interpret the often distorted images into text. Differences in radiation frequency tell us which page the signal is coming from. To improve accuracy and depth, the teams are working on filtering "noisy" signals. Museums could use this technology to read antique texts without harming them.