Sorry Cunningham but you're wrong there, Cineworld hand out special IMAX 3D glasses for their IMAX 3D films which you have to return after the screening. The IMAX 3D glasses are different to the Real D ones, so your Real D ones wont work on the IMAX screen as far as i know. The IMAX glasses don't cost extra though, so you don't need to worry about any additional cost.
You're right, thanks for correcting I miss read the question and didn't see IMAX. Appolgies to CJClarke.