Buyers show off their newly purchased Sony PlayStation Vita portable game in Tokyo on Saturday.

TOKYO — Sony’s long-awaited PlayStation Vita portable game machine hit stores in Japan on Saturday as thousands of game enthusiasts lined up early to be among the first to buy it.

Sony Computer Entertainment is predicting brisk sales, even though the launch might have missed some holiday shoppers. A successful debut would help the company offset the rest of its struggling business. Sony projects a loss of more than $1 billion for the fiscal year through March 2012, which would be its fourth straight annual loss.

In Tokyo’s Ikebukuro shopping district, some 300 game enthusiasts lined up outside a major electronics chain that opened a few hours earlier than usual for the event.

The device is a touch-interface and motion-sensitive handheld seen as a successor to the PlayStation Portable. Gamers can connect over cell phone networks and Wi-Fi hotspots, and use GPS location-tracking technology.

Television footage showed some shoppers unwrapping their new purchases and starting to try them out at the store.

For the Tokyo-based electronics and entertainment giant, the Vita is the biggest product launch since the PlayStation 3 console five years ago. It’s also accompanied by two dozen software products — the largest number of launch titles in PlayStation history.

The Vita has front and back cameras, a touchscreen in front, a touch pad on the back and two knoblike joysticks. It will enable gamers to play against each other using PlayStation 3 consoles over the Internet-based PlayStation Network.

The companies are challenged by the rise of smartphones and tablets, through which casual gamers play inexpensive and simple games like “Angry Birds.”

The PS Vita goes on sale in North America and Europe on Feb. 22.