IMAX is a proprietary system of high-resolution cameras, film formats, film projectors, and theaters known for having very large screens with a tall aspect ratio (approximately either 1.43:1 or 1.90:1) and steep stadium seating.

ManufacturerIMAX Corporation 

Graeme Ferguson, Roman Kroitor, Robert Kerr, and William C. Shaw were the co-founders of what would be named the IMAX Corporation (founded in September 1967 as Multiscreen Corporation, Limited), and they developed the first IMAX cinema projection standards in the late 1960s and early 1970s in Canada.[1]

IMAX GT is the large format as originally conceived. It uses huge screens of 18 x 24 m and, unlike most conventional film projectors, the film runs horizontally so that the image width can be greater than the width of the film stock. It is called a 70/15 format. It is used exclusively in purpose-built theaters and dome theaters, and many installations limit themselves to a projection of high quality, short documentaries.

The large costs involved in the construction and maintenance of the dedicated building and projectors suggested the introduction of several compromises in the following years.

To reduce costs the IMAX SR and MPX system was introduced in 1998 and 2004. The smaller projectors were used to retrofit existing theater, so as to spread IMAX also to multiplex and existing theater, losing much of the quality of the GT experience.

On the same line came the introduction of the IMAX Digital 2K and IMAX with Laser 4K in 2008 and 2015, extremely limited in respect to the 70 Mpixels of equivalent resolution of a 70/15 film. Both technologies are purely digital and suitable to retrofit existing theater. The Laser system present was used since 2018 to retrofit also fulldome installation, with limited results due to the large area of a dome screen.