E-Readers Get Clearer Screens, More Content

People might use their computers and phones to browse e-mail and articles, but they still prefer to read a 200-page novel on paper. That may soon change, thanks to technology that could cause demand for digital readers to explode.

Massachusetts-based E Ink has developed a way to display text without the glare or flickering that usually occurs on screens. The company's "electronic ink" consists of minute capsules suspended in clear fluid that respond to electricity to produce images. The material allows people to read screens from any angle and under any light.

Companies such as Amazon.com ( AMZN) and Sony ( SNE) are using the technology in digital readers, or e-readers, which are portable handheld devices that can download and store books, magazines and blog posts. The readers only use battery power to turn and refresh pages, so you never have to turn off the device.

Amazon recently upgraded its Kindle reader.

Here are three of the newest digital readers that use E Ink's material. Some can also play music, display images and download documents in a variety of formats.

Kindle II - $359: Amazon's upgraded digital reader comes with free access to Sprint's ( S) network, so users can download books directly to the device without using a computer. The Kindle II can store up to 1,500 books, and a two-hour charge is enough to power 8,000 page turns.

Additional perks include a dictionary that displays the definitions of selected words and a text-to-speech function, which reads content aloud from many of the 245,000 titles Amazon sells for $10.99 each.

PSR-700 - $399: Sony's digital reader features a sleek metal frame and has a six-inch touch screen, eliminating bulky buttons like those on the Kindle II. The device's screen lights up, so you can read in the dark, and refreshes quickly to make page turns more fluid. It also allows users to write notes in the text.

The PSR-700 has its drawbacks. There's no wireless connection, so you have to download books to your computer first and then transfer them to the device. Also, the Sony Connect eBookstore has about 100,000 titles, most of which cost $11.99. That's less than half the number offered by Amazon.

The Sony PSR-700 holds 350 books. If you're a Mac user, you're out of luck: the device only works with Microsoft's ( MSFT) Windows operating system. Sony also offers a less-expensive PSE-505 reader, which lacks a touch screen, for $299.

iLiad - $699: The second version of iRex Technologies' reader also serves as a notebook. Its screen allows users to jot notes in the margins of their e-books using a stylus pen without sacrificing battery power. The iLiad offers digital paper with lines for writing music, drawing graphs and taking notes. Thanks to its wireless Internet connection, you can download books directly to the device.

The iLiad's main downside is that it doesn't have its own bookstore, so owners of the iLiad must use sites such as Gutenburg.com, which offers free downloads of books in the public domain, or Mobipocket.com, where bestsellers cost $5.99 to $19.99. The iLiad only stores a few dozen books at a time, but users can increase its capacity with memory cards.

If you already own an Apple ( AAPL) iPhone or iPod Touch, you can download the Kindle application, which gives users access to Amazon's massive bookstore. However, these devices' small screens and glare might make serious reading difficult.

Harper Willis graduated from the Gallatin School of Individualized Studies at New York University with a concentration in ancient theater and jazz guitar. He is a musician and writer, and lives in Brooklyn, N.Y.

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