US Patent 7548220 Foldable electronic book

An electronic book includes a first housing portion and a second housing portion. Microprocessor circuitry is positioned in the housing portions to control operation of the electronic book. A cylindrical spine is interposed between the first and second housing portions, which are pivotally connected to the spine to be pivoted between an open condition for reading and a closed condition. A flexible display screen is fast with inner faces of the first and second housings and spans the spine. The spine defines a recess to accommodate a curvature of the screen intermediate the first and second portions, when the portions are in a closed condition.