Many of my patients have been to see the latest films in 3-D recently and often ask me how they work. So here goes…!
Normally, our brains receive two images, one from each eye, and they are put together to see in 3-D. There are certain signals that the brain recieves from the eyes to be able to produce a 3-D image rather than a ‘flat’ one, and 3-D films do this very well. The main technique is by using polarised glasses and two images of each frame of the film slightly apart from one another. That’s why when you try and watch the film without the polarised glasses, it looks smudged. One eye in the glasses is polarised to see just one of the images on the screen, and the other eue is polarised to see the other. You can try this by closing one eye when watching the film – you’ll notice you’ll only see in 2-D. When the brain receives these two images from each eye and puts them together, we see in 3-D!
Interestingly, I’ve also had children see me and say that they DON’T see in 3-D – this indicates a problem with the eyes, as both eye need to be seeing well individually to process the 3-D images correctly. As optometrists, we regularly check 3-D vision as part of a normal eye examination to highlight any problems. So come and see us if you haven’t experienced the 3-D magic!
Qausia Hassan, Bsc MCOptom