China has a strong record of approving Hollywood films that Imax wants to show.Imax, which has become one of the entertainment industry’s fastest-growing companies, has a strong brand in China because its large-format theaters, which often play films in 3-D, offer an affordable luxury. When Imax showed “Avatar” last year, Chinese customers waited up to six hours for tickets that cost about $16 each.Mr. Gelfond has spent years stalking the Chinese market, converting Chinese-made films for Imax screens (on favorable terms) and developing a portable theater to deploy in rural areas. And he is still courting. “One of the important things about this latest deal is that, over time, it increases our base so dramatically that we will be able to increase the number of Chinese-produced films that we show,” he said.