At some future date while waiting in a doctor's office, reception area, or airport, you might just decide to pass the time by pulling out your radio paper. Like some hybrid newspaper, the text on radio paper would update itself dynamically in real time, faithfully relaying radio broadcast in the form of text. Radio paper is one of the inventions yet to be realized through the technology of electronic ink.

Electronic ink is a dark, oily soup of microcapsules, or tiny clear balls. The microcapsules are filled with dark liquid that contains floating white particles. If a positive charge is applied, the white particles rise to the surface of the microcapsule, forming a white dot. If a negative charge is applied, the particles fall to the bottom, creating a black dot. By using tiny transistors across a laminated back-grid, the charged particles form text in sharp, pixelated form. Constructed with a wireless link, radio paper can be updated dynamically by changing charges along the grid.

Radio paper might be used in situations where the audio signal of a radio is unwanted or disallowed. It would also make radio broadcasts accessible to the hearing impaired. Because radio paper would use very little power and could be read in conditions with dim lighting, it might also be used redundantly with other means to relay valuable information in times of crisis, such as during natural disasters.

The ultra-thin display of radio paper promises to read more like real paper versus a computer screen or LCD (liquid crystal display). Aside from radio paper, we can also expect novels that 'morph' into new books, newspapers that never need to be thrown away, and magazines that update themselves. Industry insiders claim potential applications for electronic ink will revolutionize the publishing industry while saving natural green resources through drastically reducing paper waste.

Electronic ink is not new, though developments in miniaturization and wireless technology have made it more recently viable for practical applications in the marketplace. Lucent Technologies manufactures the tiny transistorized grid that makes electronic ink possible, while the ink itself is proprietary, made by companies like E. Ink Corp. and Xerox. Although electronic ink is in use commercially in limited applications, as of mid-2005 radio paper is still on the horizon.