What is a 3d movie?

3d movie is a kind of stereoscopic movie, which makes the audience feel the depth and realism of the movie picture by using the principle of human stereoscopic vision and special projection technology and glasses. The principle of 3D movies is that when human eyes observe the same object through their left and right eyes, the images received by the two eyes will be slightly different due to the different viewing angles. After these differences are processed by the brain, we can distinguish the front and back and the distance of the object, thus producing stereoscopic vision. In 3D movies, this stereoscopic effect is shot from different angles by two cameras showing at the same time and presented to the audience on the screen. By wearing special polarized glasses, the audience can only see the image at the corresponding angle in each eye, thus forming a three-dimensional effect in the brain.