Of course, even with their current, monochromatic text, e-book readers have already been strong sellers, said Vinita Jakhanwal, director of small and medium displays at the market researcher iSuppli. Worldwide shipments have risen quickly — to 11 million in 2010, from 5 million in 2009, she said, with 15 million predicted for 2011.
But the popularity of the Apple iPad, on which people can read books, surf the Internet, watch videos and enjoy thousands of apps — all in full color — has shaken up the market. “It’s forced e-book reader manufacturers to innovate,” said Paul Semenza, a senior vice president for DisplaySearch, an industry researcher in Santa Clara, Calif.
Major e-reader companies like Amazon.com, which sells the Kindle, and Barnes & Noble, seller of the Nook, have not announced that they are offering color versions, or that they are committed to a specific technology for doing so. But some smaller entrants in the market have said they will be using liquid crystal displays, just as the iPad does.
The Literati by the Sharper Image, for example, has a a full-color LCD and will go on sale in October, priced at about $159. And Pandigital has said that the Novel, its full-color e-reader with an LCD touch screen, will be at retailers this month at a suggested price of about $200.
But LCD displays have disadvantages, Mr. Semenza said. They consume a lot of power, he said, because they need backlighting and because much optical energy is lost as light passes through the polarizers, filters and crystals needed to create color. They are also hard to read outdoors, he added.
Other types of displays may also find a foothold with consumers — particularly low-power, reflective technologies that take advantage of ambient light and are easy to read when outside. The EInk Corporation in Cambridge, Mass., uses this reflective technology for its present product — the black-and-white displays in the Kindle, Nook and other e-readers — and will soon introduce a color version of the technology, said Siram Peruvemba, E Ink’s vice president for global sales and marketing. The technology will probably first be used for textbook illustrations and for cartoons.