The new gadget, which can be used like a conventional clam-style notebook PC with a software keyboard, or turned 90 degrees for use as an e-book reader, will go on sale in Japan in late August and later in Europe, the United States and other markets.
Toshiba unveiled the Libretto W100 at a lavish event in Tokyo that also marked a quarter century since it launched the world's first laptop in 1985, though its personal computer division made an 8.8 billion yen ($97 million) loss in the year to March 2010.
The company expects its PC division to break even in the year to March 2011.
The new touch-screen gadget, which also faces potential competition from Sony Corp will not shake up the e-book reader market at this point, because the company has yet to draw up any agreements with content providers.
But executives were keen to emphasize that the Libretto, which they expect to retail for about 120,000 yen ($1,320) in Japan, compared with $489 for the larger of Amazon's Kindle devices, or $499 for the cheapest iPad, offers more than a passive "consumption" experience.
"Apple's iPad is probably creating a new market in terms of consuming information, browsing and reading books," Masahiko Fukakushi, president and CEO of Toshiba's digital products and network unit, told reporters.
"But when it comes to creation or production ... what we have been doing still has a lot of value. We want to continue to do both."
Toshiba is the world's fourth biggest notebook PC vendor after HP, Acer and Dell. Industry-wide shipments of notebook computers jumped 43 percent in the January-March quarter, their highest year-on-year growth in eight years, according to industry tracker Gartner.
Toshiba is targeting global PC shipments of 25 million units in the year to March 2011.