This is the summer that 3-D films will start to hit their stride — or at least Hollywood is hoping that's the case.

Emboldened earlier this year by the phenomenal success of "Avatar" and a few solid 3-D films that followed, the movie industry is banking that this rising medium, which helps to fatten any release's box-office numbers, will take off.

Starting with last week's "Shrek Forever After,"which pulled in $71.3 million at the box office, seven 3-D films will hit theaters before the summer movie season ends on Labor Day, four of which will be animated. That includes a duel of sequels between two computer-animation franchise behemoths, Dreamworks' aforementioned "Shrek" and Walt Disney Co.'s "Toy Story." The five films in the two franchises have made a cumulative $3 billion worldwide.

But the hope is that those hefty receipts will get even heftier with padded 3-D ticket prices, which average $3 more than regular 2-D theaters, and are approaching nearly $20 apiece for big-screen showings in pricier metro areas such as New York and Los Angeles. Some prognosticators think it could help Hollywood set new revenue records, even if the industry doesn't put any more people in the seats.

"It's skewing things in favor of a higher gross," said Paul Dergarabedian, president of box-office analysis for Hollywood.com.

Dergarabedian says that 25 percent of the industry's year-to-date domestic receipts have come from the four 3-D films released thus far, including the new all-time box-office champ "Avatar." That film has returned more than $747 million in North America and $2.7 billion worldwide, and is a product of Twentieth-Century Fox. (Fox, like MarketWatch, is a subsidiary of News Corp.)

The other 3-D releases from this year — Disney's "Alice in Wonderland," DreamWorks' "How To Train Your Dragon" and "Clash of the Titans," from Warner Bros. — all have seen healthy returns as well, thanks to a boost from the pricier showings. They range from "Dragon's" $388 million in worldwide receipts to "Alice's" $879 million.

Dergarabedian says traditional year-to-date figures show a 6.3 percent jump in revenue with a 4.2 percent increase in attendance — the difference in growth due to higher ticket prices. But he says the number of viewers is calculated from the industry's average ticket price of $7.61, which doesn't take into account the 3-D premium. If 3-D prices were stripped out, attendance actually would be down slightly, Dergarabedian says.

Charles Viane, president of Disney's distribution operations, said while 3-D is gaining momentum, it still has to make sense.

"The bottom line is you still have to make a good movie," he said. "I think it lies mostly in the hands of our filmmakers, who use 3-D, like any other tool, to enhance their filmmaking."

Disney is making the biggest splash, however, in 3-D this summer with two films using the medium, "Toy Story 3," due out June 18, and "Step Up 3-D," scheduled for Aug. 6.

The others include: DreamWorks' "Shrek Forever After," out last week, and "The Last Airbender," a film from "Sixth Sense" director M. Night Shyamalan and Viacom Inc.'s Paramount Pictures, on July 2.

There's also the animated "Despicable Me" a week later on July 9 from Universal Pictures, "Cats & Dogs: Revenge of Kitty Galore" from Warner Bros. on July 30, and "Piranha 3-D" from the Weinstein Co. on Aug. 27.

Viane says the industry will begin to get an idea of how big the public's appetite for 3-D films is this summer. In most cases, though, there is a three- to four-week gap between most of the 3-D releases. The one-week break between "Airbender" and "Despicable Me" will offer another test.

The real test comes in the fall, Viane says, as the number of 3-D releases will heat up after Labor Day. Another 10 films are set to debut through to the end of the year, with many coming out just a week or two apart.

"We're going to see every possible scenario in the fall," he said.

While some say youths will demand 3-D from now on, others aren't so sure.

"So far, 3-D is enhancing the box office with several of these titles. We'll see if people are still thirsting for 3-D," said Brandon Gray, president of BoxOfficeMojo.com. "You're either oohing and aahing at the technology or you're adjusting your glasses because they're digging into your skull."