What makes an 'Imax' 3D cinema image 3D?

I was discussing 3D stereograms last year in relation to Channel-4's 3D week, but I came across this interesting video clip on the BBC website when I was looking for information on 'The Pixar Story' a documentary "about the pioneering computer animation studio ".

The 3D shown here does not require coloured filters in the glasses, but does still adhere to the age old principle that 3D is constructed in the brain from seeing two slightly different images with each eye. Rather than coloured filters these use polarising filters. This gives the best colour reproduction of all the 'cheap' glasses methods - but I will let the video tell you more:



Further information may be found here >