What's the difference between 3D movies and 4D movies?

D is the prefix of English Dimension, and 3D refers to three-dimensional space. Internationally, 3D movies are used to represent stereoscopic movies. There are many forms of making 3D movies, among which polarized glasses method is widely used. It uses human eyes to observe the scenery, uses two parallel movie cameras to represent people's left and right eyes respectively, and shoots two movie pictures with tiny horizontal parallax at the same time. During screening, two films are respectively loaded into the left and right film projectors, and two polarizers with polarization axes of 90 degrees are respectively installed in front of the projection lens. The two projectors need to run synchronously and project the picture onto the metal screen at the same time to form a double image of the left image and the right image. When the audience wears special polarized glasses, the polarization axes of the left and right polarizers are perpendicular to each other and consistent with those in front of the projection lens; The viewer's left eye can only see the left image, and the right eye can only see the right image. The left and right images are superimposed on the retina through binocular convergence function, and the brain nerve produces stereoscopic vision effect. Presenting a continuous three-dimensional picture, let the audience feel that the scenery is coming, or enter the deep recess of the picture, which can produce a strong sense of "being there".

4D cinema is a new film and television product based on 3D stereoscopic movies and simulated environmental special effects. The so-called 4D movies are also called 4 D movies; That is, a three-dimensional movie and the surrounding environment simulate to form a four-dimensional space. When watching a stereoscopic movie, the audience can feel the events around them corresponding to the stereoscopic image in real time, such as storm, lightning, rain, collision, water spray fog, leg slapping and so on. The 4D seat has the functions of spraying water, spraying air, vibrating and sweeping legs. , powered by pneumatic device. Environmental simulation refers to the installation of snow, rain, lightning, smoke and other special effects equipment in the cinema to create an environment consistent with the content of the film. Both of the above films have immersive and thrilling effects. These two films have both commonness and individuality. Being in the mirror, thrilling and feeling technology are their commonalities; One is to feel stimulation in sports, and the other is to feel stimulation in vision. This is their personality.