Multiplex operators continue to warm up to the IMAX (Nasdaq: IMAX) money tree.

AMC Entertainment is expanding its joint-venture partnership with the provider of larger than life cinematic experiences.

Two years ago, AMC and Regal (NYSE: RGC) were the first exhibitors to sign joint venture deals with IMAX. Instead of simply selling or leasing its high-end projection equipment, IMAX would help foot part of the bill, in exchange for a thicker slice of the box-office receipts and a cut from concessions.

AMC and IMAX have 79 North American screens in operation, with plans to open 25 more later this year. This would wrap up the original deal, but now AMC and IMAX are agreeing to open as many as 25 new screens next year. The length of the arrangement will also extend from seven years to a full decade.

As a result of the expanded deal, IMAX now feels it can open more than the 400 screens it previously envisioned in North America.

The joint ventures have played out perfectly. IMAX's empire has grown dramatically, and so has its profitability. IMAX is coming off its best quarter in the company's 43-year history. Revenue more than doubled, and last year's small quarterly loss was transformed into a market-thumping $0.40-a-share profit. Analysts now expect IMAX to earn $1.06 a share this year. Just three months ago, Wall Street figured the company would deliver a profit of just $0.60 a share.

This morning's deal also validates the IMAX model. Three months ago, investors fretted over AMC's decision to introduce its own IMAX clone. It opened an AMC ETX (enhanced theater experience) screen in Florida. Was the proprietary super-sized experience an expansion vehicle or a negotiating ploy? Does it matter?

"Our guests clearly choose to see movies in our IMAX auditoriums because the experience is unparalleled in terms of sight and sound," AMC CEO Gerry Lopez notes in the press release. This isn't the kind of endorsement that AMC would make if it were serious about ETX as a potential IMAX killer.

IMAX isn't just about richer projections and superior sound systems. It's become a brand to reckon with, as every studio trips over itself to make sure that its blockbusters are mastered for high-end IMAX screenings. I was fortunate enough to recommend IMAX to Motley Fool Rule Breakers subscribers five years ago, while it was still in the single digits.

The new deal isn't a guaranteed victory for IMAX, however; expanding the number of screens and length of arrangement comes with a price. According to the release, the new terms offer an "adjusted allocation of costs to help defray AMC's increased operating expenses." In short, IMAX will foot a bigger chunk of the up-front installation costs.

That's OK. IMAX has proven that its fortunes get better and better with a larger installed base. Sure, it has News Corp.'s (NYSE: NWS) Avatar, Disney's (NYSE: DIS) Alice in Wonderland, and DreamWorks Animation's (NYSE: DWA) How to Train Your Dragon to thank for its monster first quarter, but it wouldn't have materialized if global exhibitors weren't flocking to IMAX.

Have you ever been to an IMAX theater? Was it worth the premium? Please share your perspective in the comment box below.

Walt Disney is a Motley Fool Inside Value selection. IMAX is a Motley Fool Rule Breakers pick. Walt Disney and DreamWorks Animation are Motley Fool Stock Advisor recommendations. Try any of our Foolish newsletter services, free for 30 days.

Longtime Fool contributor Rick Munarriz is a movie buff, owning shares in Disney. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. The Fool has a disclosure policy.