LOS ANGELES (AP) — By the end of the decade, Darth Vader could be rattling sabers with his enemies above the heads of moviegoers, and Buzz Lightyear could be flying off the screen on his way to infinity and beyond.For real — or at least the cinematic version of real: 3-D.

A growing number of blockbuster, live-action films and animated movies are expected to be offered in in-your-face 3-D in the next few years, as thousands of theatres are outfitted with the special projectors and screens needed to show the films.

Jeffrey Katzenberg, chief executive of DreamWorks Animation SKG Inc., is so gung-ho about 3-D that he has said his studio might start exclusively releasing movies in the format as early as 2009 with its "Monsters vs. Aliens".

"For Memorial Day weekend 2009, I would like to see 3,800 locations and 6,000 screens that we can put our movie on. And if they are there, then we will be exclusive in 3-D," Katzenberg said at a recent investors conference.

So far, moviegoers have reacted positively to the few 3-D films that have been released in recent years.

"Meet the Robinsons" from The Walt Disney Co. debuted on March 30, earning $25.1 million in its opening weekend.

More than a quarter of that revenue came from the 581 screens across the country that showed the film in 3-D, the company said. Those moviegoers were even willing to pay a few extra bucks to don special glasses and watch characters leave the screen.

A number of high-profile filmmakers have 3-D projects in the works, including Peter Jackson, Robert Zemeckis and James Cameron.

Walt Disney Co. has released 3-D versions of three animated films and recently signed a deal with Zemeckis to produce more. The studio is also rumoured to be making the sequel "Toy Story 3" in 3-D, a report the studio declined to confirm.

These days, 3-D films are more than just a gimmick.

For theatre owners and studios, the technology could be a lifesaver, luring people back to multiplexes for an experience that cannot be matched by sophisticated home-theatre systems or stolen by pirates with hidden camcorders.

The theatre industry is also battling competition from video games and other alternative entertainment along with Internet downloads that will soon deliver high-definition films directly to homes.

Film exhibition companies looking to protect their business believe 3-D will boost revenue. Some industry executives think theatres can add as much as 50 percent to the cost of a ticket for a 3-D feature.

"If we can sell ten percent to 15 percent of our tickets annually at a higher price point, that's a real mover of the needle," Mike Campbell, chief executive of Regal Entertainment Group, the nation's largest theatre chain, said at the investors conference.

About 700 theatres across the country are now outfitted with 3-D technology, with thousands of others moving to spend the $17,000 needed to install the equipment.

Moviemakers, meanwhile, estimate that making a movie in 3-D can add as much as $15 million to the cost.

Today's 3-D technology is far more advanced than that used in the 1950s, the heyday of gimmicky 3-D films.

Previous 3-D systems projected two images on the movie screen, one for each eye. That required the use of red and blue lenses or even glasses with mechanised shutters that opened and closed quickly to separate the images.

With newer systems, moviegoers still need to don special glasses but not the cheap cardboard variety with blue and red lenses.

Instead, special polarised lenses will separate the stereo images projected on specially coated screens.

RealD, a Beverly Hills company, is the leader in modern 3-D with systems that will be operating on about 1,000 screens by the end of the year.

Its technology uses a special movie screen painted with a silver oxide to direct more light back to the viewer instead of scattering wavelengths the way normal screens do.

The theaters also use digital projectors that show movies stored in bits on a computer hard disk rather than traditional film.

Dolby Laboratories Inc. recently unveiled plans to market its own 3-D technology that would work with existing movie screens.

"The momentum is gathering, and I think this is probably the most exciting thing from a filmmaking and filmgoing experience that has happened in my time in the business," Katzenberg said. "There's nothing more compelling than this."