3D Movie Glasses

Have you ever wondered how putting on those 3D movie glasses can change a 2D film into an amazing 3D experience? What is it about those glasses that make this possible, and why is it they used to be two different colors but now apparently normal clear plastic glasses can do the same thing but better? The following will explain how both these methods work and why 3D movies are improving and making a comeback.

You have probably noticed the recent growth in popularity of 3d films, represented perfectly with the huge hit ‘Avatar’, you may even remember the boom in 3d films between the 50’s and 80’s, even if you do not we all have that image in our head of an awestruck audience scoffing down popcorn each with cardboard glasses on made of red and blue lenses.

Until now however it was always more of a gimmick to have a film displayed in 3d, this is all changing thanks to new more popular methods of producing the impressive 3d effect in films.

There are two ways in which 3d movie glasses are used in order to create the 3d experience, they each work by taking advantage of the way in which our brains process information and create depth perception. Our perception of depth is created by our eyes being spaced apart and therefore receiving two slightly different images, our brain processes this information and translates it into an image with depth. 3d movie glasses use this to create 3d images.

The original method uses the well known red/blue or red/green cardboard glasses; this system uses anaglyph images to create a stereoscopic 3d effect. As already discussed the eyes see two slightly different images as it is which are then combined to produce a single image, with the use of anaglyph images this process is used to produce the 3d effect, two different images are produced for a single  frame each is slightly different. Each image is processed in a different color and the lenses of your 3d glasses filter out each color so only one image is seen by each eye, your brain then does what it does best and combines these images to produce a single image that has a feeling of depth, the movie then goes from plain old boring to everything you can imagine jumping right out at you! If you were to watch the film without your 3d movie glasses on you would notice how blurry it looks, without the glasses filtering out each image for each eye your brain is unable to create the 3d effect. This method works well but is seriously handicapped by the fact that colors are used to create the effect, therefore using it in color films is difficult and restricted leaving the image quality with room for improvement.

The new method to make 3d movies is far more convenient because it does not use colors in order to create the effect, therefore leaving the image quality untouched. If you have seen a film in 3d recently it will have been with this new polarized method, you may have even been wondering how it could work without needing different color lenses, the 3d movie glasses used now are plastic framed with clear lenses. These new polarized glasses work in the same way the old glasses worked, by allowing only one of two images to be seen by each eye but the way in which they filter these images has changed. In case you didn’t guess they do this by taking advantage of the polarization of light waves. Put simply the polarization of waves refers to the fact that each light wave oscillates, with polarized 3d movie glasses only certain images are filtered through each lens, this is done by only allowing light through that is moving in a certain way. So for example one lens will allow vertical light waves through whilst another will only allow horizontal, all that is left to do then is project two images onto the screen each polarized in a different way, your brain then correlates these images and creates depth. Thanks to the fact this method does not rely on color to create the 3d effect, the image quality of the movies will not suffer.

So now you know how those magical little glasses manage to change a dull film into an amazing 3d experience, no longer do we need to watch arrows flying across the screen but instead we can watch them flying straight for us!