With all the modern technology nowadays, it’s pretty darn boring to go and see your everyday 2D movie at the movie theater. Instead, we love to have aliens, zombies and dinosaurs jumping out at us (well, apparently we do anyway). Although it may seem like a relatively new invention, 3D glasses and 3D projections have been around for decades. Remember the View-master you always used to play with as a kid? That uses the same kind of technology.
How do we see in 2D?
It’s interesting to note how our eyes perceive 3D images. What’s so different to 2D images? Are our eyes just having a bit of a meltdown? In fact, when we normally see, in everyday 2D vision, our eyes are seeing two different images at all times. Obviously, our eyes are not one (that would be weird, a new generation of Cyclops) and are spaced around 2 inches apart from each other. This means that each eye is seeing the world from two different directions, spaces, and perspective. However, because our brain has developed to combine and correlate these two different images together, we only see one final image.
How do we see in 3D?
Being able to see in 3D relies on us being smarter than our own brains and overpowering the natural instinct. The idea behind 3D imaging is simple. In order to see a movie or a book or a View-Master in 3D, each of our eyes needs to see something different – and we need to stop our brain from merging them together. When you go and see a 3D movie and take off your glasses, you’ll notice that you cannot focus on the image at hand. This is because these 3D movies are forcing two different layers of imaging on top of each other to create a 3-Dimensional effect. So how do we make our eyes see both at the same time? Well, that’s where 3D glasses come into play.
How do 3D glasses work?
For many years, scientists have known that different colors enter the eyes in waves of different speeds and intensities – their individual wavelengths. The shortest wavelength of visible light is violet (with the wavelength even shorter than that being the invisible ultraviolet or UV), and the longest wavelength of visible light is red (with the wavelength longer than that being the invisible infra-red). When looking at 3D imaging, scientists began to work with different colors to enhance these images. During their investigations, they found that using glasses with two different colored filters stopped the eyes from merging the two separate dimensions or images together to create one full image. Instead, the filters only allow one image to enter each eye, and the eyes layer these two on top of each other to create more depth to the image. This is why our 3D glasses normally have one red and one blue lense.
3D colored lense glasses were the first major breakthrough when it came to 3D imaging and 3D movies, and are still used today. However, science is constantly trying to better itself and have realized that there may be a better, and easier way to see in 3D. Many theme parks, like Disney World, and most cinemas screening 3D films, have now adopted a new system to allow their visitors to be part of their 3D movies and experiences. Instead of using the color lenses, they are now using polarized lenses as they offer enhanced colors, brightness, and vibrancy. In this instance, two projectors show two views and directions of an image onto the movie screen – but both of them have a different polarization to the other. The glasses given to the audience have themselves got lenses with different polarizations to each other. Because of this, each eye will only see each respective polarization, leading to a 3D image.