Traditional Culture Encyclopedia - Photography and portraiture - Can ordinary LCD TV watch 3D pictures? What glasses do you want me to buy?

Can ordinary LCD TV watch 3D pictures? What glasses do you want me to buy?

Ordinary TV can't watch 3D pictures.

Three-dimensional video TV uses the principle that people's eyes observe objects at slightly different angles, so it can distinguish the distance of objects and produce stereoscopic vision, and separate the images seen by left and right eyes, so that users can experience stereoscopic feeling with their naked eyes without using stereoscopic glasses.

As for this imaging principle, it involves several 3D technologies:

1, shutter 3D technology

The realization of shutter 3D technology requires a pair of active LCD shutter glasses to alternate the images seen by the left eye and the right eye, so that your brain can fuse the two images into one, thus creating a 3D depth sense of a single image. At present, the 3D TVs launched by Samsung and LG mainly adopt this 3D display technology.

The essence of shutter 3D technology is realized according to the refresh time of image frequency by human eyes. By increasing the fast refresh rate of the image (at least 120Hz), the 60Hz fast refresh image of the left and right eyes will make people feel no jitter, keep the same frame number as the 2D video, and let the audience's eyes see the different images that are quickly switched, which will create illusions in their brains, and then watch stereoscopic images.

2. Polarized 3D technology

Polarized 3D, also called polarized 3D technology, belongs to passive 3D technology, and the price of glasses is relatively cheap. At present, polarized 3D technology is mostly used in 3D cinemas and 3D LCD TVs. Like shutter 3D technology, polarized 3D is subdivided into many categories. For example, polarized 3D applied in projector industry needs more than two projectors with the same performance parameters to achieve 3D effect, while polarized 3D applied in TV industry needs a refresh rate of more than 240Hz. There are many differences between them in implementation.

From the technical mode, polarized 3D technology is also called passive 3D technology because it is passive reception. The cost of auxiliary equipment is low, but it requires high output equipment, which is very suitable for commercial theaters and other places that need a large audience.

There are two polarization techniques, namely linear polarization and circular polarization;

Linear deflection: one polarization component of incident electromagnetic wave is blocked, and the other part of linearly polarized wave passes through.

Circular deflection: firstly, linear deflection is carried out, and then the passing part of the linear deflection electromagnetic wave is processed to form a circularly polarized wave.

Circular deflection adds a phase difference film on the basis of linear deflection, which can make the deflected light rotate clockwise and counterclockwise. In addition, because this film must be added before the linear deviation, the circular deviation is divided into about two parts. Because of the phase difference film, the angle of circular deviation can be larger than that of straight line deviation, which means you can watch movies with your head tilted.

The method of naked eye line deviation and circle deviation: when the line deviates inward or outward to the screen and rotates 90 degrees with the line scanning of the computer screen, the screen light is completely blocked and appears "black"; But because of the difference between inside and outside, no matter which angle you shoot, there will be no "black screen" on one side, which has the same effect as line deviation.

Regarding the phase difference film, if a thin layer of ordinary plastic is added in front of the linear deviation, you can also see the basic taste of circular deviation, but you can't get the effect of circular deviation! ! !

3, naked-eye 3D technology (that is, watching 3D TV without glasses)

Naked eye 3D can be divided into three types: light shield, lenticular lens technology and directional backlight.

Because people's eyes observe objects from slightly different angles, they can distinguish the distance of objects and produce stereoscopic vision. Three-dimensional video TV uses this principle to separate the images seen by the left and right eyes. The stereoscopic display effect of 3D LCD TV is to send the encoded 3D video images to people's left and right eyes independently by adding a special precision cylindrical lens screen on the LCD panel, so that users can experience stereoscopic effect with their naked eyes without using stereoscopic glasses and be compatible with 2D images.

Where do 3D images come from? It boils down to "visual transfer". Let's start with the eye, which is the most important organ in the world. People's eyes are about 6 cm apart, which means that if you look at an object, your eyes look from the left viewpoint and the right viewpoint respectively. The left eye will see the left side of the object, while the right eye will see her middle or right side. When the object seen by both eyes is imaged on the retina, the left and right impressions are combined to get the final stereoscopic impression. And the effect of this stereoscopic effect is "visual displacement".

When shooting images, professional 3D cameras have two lenses to shoot images at the same time, simulating the parallax between the left and right eyes. When playing, the two films are played at the same time, and the necessary technical means are added during the screening, so that the audience can only see the left eye image with the left eye and the right eye image with the right eye. After the last two images are superimposed by the brain, we can see a picture with three-dimensional depth. As mentioned above, 3D display is divided into left and right eye images, and auxiliary devices are needed to control human eyes to perceive the left and right eye images, which is the function of 3D glasses. Now active shutter glasses are all controlled by liquid crystal, which is controlled by liquid crystal molecules.

Motion controls the perception of the left eye or the right eye, and the refresh rate is 60Hz, which is why 3D TV requires the panel refresh rate to be at least 120Hz.