NEW YORK — BlackBerry maker Research in Motion unveiled the PlayBook, a tablet computer, at a developer conference Monday.

The tablet market is so far dominated by Apple and its popular iPad, but other tech companies are trying to cash in as well.

“Every successful professional has a great PlayBook,” said Mike Lazaridis, co-chief executive of RIM, at the BlackBerry Developer conference in San Francisco.

The PlayBook tablet features a 7-inch screen, Flash-capable video and a front and rear high-definition camera. It’s thin, at just 9.7 millimeters, and weighs 0.9 pounds. Lazaridis did not name a price.

For now, the PlayBook — which will be released in 2011 — can connect to the Internet only via Wi-Fi. RIM said it plans to offer 3G and 4G models sometime in the future.

Still, Lazaridis said RIM’s goal was “to offer an uncompromised Web experience.”

The PlayBook includes a 1 GHz dual-core processor and 1 GB of RAM. It’s compatible with HDMI video output and Bluetooth, as well as microHDMI and microUSB.

The tablet won’t use RIM’s newly launched BlackBerry 6 operating system. Instead, it’s built around a new platform from QNX Software Systems, which RIM acquired earlier this year.

A QNX representative also appeared at the conference and said the PlayBook will offer “just a great gaming experience.”

Lazaridis said the BlackBerry Messenger system will be “opened as a social platform for applications,” but he didn’t give any further details. He also said in-app payments and a BlackBerry advertising service will “generate revenue immediately.”

Shares of RIM rose about 2 percent in after-hours trade Monday, but the stock is down nearly 30 percent this year due to concerns that the company is falling behind Apple as well as smartphone makers using Google’s Android operating system.

The PlayBook is being released at a critical time for RIM. The company surprised its critics by posting strong sales and subscriber growth last quarter, but its just-launched BlackBerry Torch failed to make a splash in the smartphone market.