The progressive miniaturization of electronics is familiar to everyone; computing power that used to occupy a room can now be put onto a single integrated circuit. Miniaturization is admirable when size is not relevent to the electronic function, but there are plenty of devices in which a large physical size is essential. Many of these concern information technology, examples being the computer display, printer, and fax machine. Communication with the electronic world is primarily visual and operates at a large format typified by a document. In this rapidly advancing field, we are eagerly awaiting desktop interactive display surfaces that can input as well as display information, document readers, truly portable computers, electronic vision and—the oldest dream of all—the television that hangs on the wall. Realization of these hopes requires a set of technologies that permit bigger rather than smaller electronic systems, and amorphous silicon is helping to make this happen.