IMAX Dome Screen
The theatre consists of a massive hemispheric screen, twenty-three metres in diameter. This screen is sixteen metres or about five storeys high, and is made up of 376 pieces of vinyl-coated aluminium panels, covering a surface of 625m2. The material is specially chosen to achieve thirty percent reflectivity on the hemispheric screen, thus ensuring that the images are of immense clarity.
About 43.54 million perforations in the screen allow both sound and cold air from the air-conditioners to pass through the screen to the audience. Stretching 180 degrees horizontal from wall to wall and tilted at a 30 degree angle to the horizon, the screen ?wraps? over the audience to cover 80 percent of a hemisphere so that the images when projected, will far exceed a person's field of vision - a lateral view of 180 degrees and a vertical view of 125 degrees.
Large Format Film
The theatre screens the largest film size format in the history of motion picture - a film frame ten times larger than the conventional 35 mm film and three times larger than a 70 mm frame. Projected through the fish-eye lens, it fills the hemispheric screen with brilliant images. A full reel of 60-minute film weighs 100 kilograms.
IMAX Projector
IMAX projectors are the most advanced, powerful and highest-precision projectors in the world, and the key to their superior performance is the proprietary 'rolling loop' film movement. The Rolling Loop advances the film horizontally in a smooth, wave-like motion. During projection, each frame is positioned on fixed registration pins, and the film is held firmly against the rear element of the lens by a vacuum. As a result, the picture and focus steadiness are far above the normal projection standards and provide outstanding image clarity.
The projector incorporates a unique 180 degree Leitz wide-angle lens, which uses a powerful 15,000-Watt water-cooled xenon lamp, similar to the one used to light NASA's launching pads.
The Quick Turn Reel Unit (QTRU) does away with film rewinding. This dramatically reduces film wear, which is crucial in maintaining the highest clarity standards. Its five platters also allow for four typical 40-minute large format films or a maximum of two 40-minute films and two 150-minute films to be in a ready state at any one time.
Sound System
The theatre's acoustics is designed to ensure that the theatre is soundproof to external noise as well as air-conditioning. The entire structure of the theatre is designed to achieve a Noise Criterion of not exceeding NC 25 (between 30 dBA to 32 dBA).
The ceiling and walls are thick and acoustically treated to be sound absorbing. Fibreglass insulation 125 millimetres thick is hung a distance away from, rather than attached directly to the structural surfaces. A total of 1,528 acoustic panels, each measuring 1.2 metres by 1.2 metres, covers 2,271 m2 of the entire inner surface of the theatre - enough to cover half a football field.
The theatre has twelve complete sound reproduction channels, of which six at a time can be fed from the sound reproducer. Very low frequencies are handled by a seventh channel, which is the sub-bass system.
Twelve clusters of four-way speaker systems are suspended by chains from the walls and from the ceiling outside the projection dome surface. These speakers are placed equidistant from the centre of the theatre so that the sound is perceived as coming from the intended visual location on the screen. Each speaker system comprises two JBL 2240 18-inch cone woofers covering the range from 80 Hz to 250 Hz; two JBL 2202 12-inch woofers (250 Hz to 800 Hz); a JBL 2445 mid-range driver with a custom-fabricated horn (800 Hz to 5 kHz) and a JBL 2404 tweeter (5 kHz to 16 kHz).
Each driver has its own amplifier, with 300 Watts each for the woofers, 100 Watts for the mid-range and 50 Watts for the tweeters. Built into the amplifiers are adjustable corrections for high-frequency screen attenuation, horn response and time alignment. Frequencies below 80 Hz go to a separate 6,000 Watt sub-bass system with twelve 18-inch drivers in a large ported enclosure.
There are altogether seventy two amplifiers in the theatre with a total power output of 20,000 Watts. This is more than the power produced by two hundred and fifty 75-Watt home stereo sets.