Technology

Electrochromics: Wafer-thin displays

A stock ticker on a banana? Electrochromics might make it possible.

Imagine an ink-jet printer that spits out functioning, high-quality display screens. Sound far-fetched? Several small R&D companies are working on it. Their technologies depend on a phenomenon called electrochromism — the ability of certain chemicals to change colour when electrical currents are applied. Minnesota-based Aveso Inc., a spinoff of Dow Chemical, says it can make simple, paper-thin displays printed using readily-available materials and equipment. Philadelphia-based Ntera (which dubs its techniques “nanochromics”) makes similar claims. Initial prototypes are not dissimilar to crude displays on pocket calculators, but electrochromics promises ultra-thin full-colour displays complete with integrated microprocessors, batteries, photovoltaics, wireless antennas and other components, printed out much like paper documents.

One application might be a credit card that displays its current balance. Electrochromics might also revolutionize consumer packaging, by allowing interactive displays with anti-counterfeit and anti-tamper measures. But electrochromics seems to be one of those technologies that is always just around the corner, and technology writers have been boasting of the possibilities of printed displays since at least 2005. “Nobody’s using this kind of new technique in mass production,” says Paul Semenza, senior vice-president at DisplaySearch, an industry research consulting firm. “There’s a lot of pieces that have to come together still.” Both Ntera and Aveso have been around awhile (Ntera was founded in 1998), but with LCDs finding ever-widening applications, electrochomics may be supplanted before ever reaching the market.