Since its creation, the cinema has evolved a lot: it gained sound, colors and special effects. One of the biggest news was the 3D movies, which nowadays have already become common in movie theaters and even at home it is posible to see them on special televisions. How is this effect created?

What is 3D?

The abbreviation 3D means three dimensions. That is, instead of having two dimensions, height and width, the perception of depth was became posible, which is the third dimension. It is what makes the scenarions, peoble and cartoon characters look more real, as if they were closer to the viewer.

How is the 3D effect created?

To understand the 3D effect, firstly we need to think that humans have binocular vision, that is, each eye sees the image in a different way. These two sources of vision that allow us to see normally in 3D.

In cinema, this image is formed thanks to a phenomenon called stereoscopy, which consists of the project of image of same scene at different points of observation. When 3D movie produsctions began for the cinema, anaglyph images were used, which include two layers of color on a single trip of film played by a projector, one of the layers red and the blue (or green). So it was necessary to use the 3D glasses with a rea lens and the other blue (or green), because they helped our brain to interpret the two layers as three-dimensional image.

With modernization of the 3D theaters, the polarized mode is now used. This technique is more faithful to the movie and maintains the original colors. In this regard, each image is projected with a different polarity, sometimes even with two projectors at the same time. So to watch the movies, we also need glasses with special lenses, and which lens has a different polarization filter: one lens filters the polarized waves vertically while the other horizontally. As the polarized lens darkens the images a bit, the projection screen must be silvary to increase the brightness of the image.

Do you want to study and to understand a bit more about optical physics and 3D effects? Magic Hologram – Mirage 3D is ideal for studies on the subject.