With a period of 2 minutes and 38 seconds of programming, Liaoning Satellite TV's Spring Festival Evening swept Weibo WeChat. In the Liaoning Spring Festival Gala held on the evening of the 6th, six young children presented the audience with a highly ornamental program, “The Monkey Monkeyâ€, and was stunned.
When the music rang and the teacher Zhang Jinlai waved the golden cudgel, there was a feeling of time and space intertwined. The two ends of the golden cudgel were connected to childhood and now, the golden monkey returned, awakening feelings, bursting 3D special effects, giving you a The Monkey King, who enjoys the fog and fog.
How is this special effect achieved?
As early as the award ceremony for the 2014 Billboard Music Awards, this technology was used to "revive" the deceased King Michael Jackson. In the CCTV Spring Festival Gala in 2015, Li Yuchun sang "Sui Xiu" also used a similar technique. What kind of technology is this?
In fact, this 3D holographic projection technology is not particularly new, but it does not use real holographic technology. Dimensional dynamic holographic laboratory still in the initial stage, mainly by the spatial light modulator (Spatial Light Modulator, SLM) to achieve, that the gadget FIG.
The phase-sized SLM, which is the size of the thumb lid on the right side of the picture above, is priced at RMB 100,000 or more. It is necessary to build a system that can be seen in the past. For example, a certain set of big bangs project a small globe. Its implementation is much smaller. It can't be done without millions of dollars.
A small globe projected in a set of big bang
The following figure is the SLM array device, it is definitely burning money!
Not only the cost, computational holograms require a great amount of calculations, and the computational volume of the three-dimensional plane is much larger. Scholars have proposed many algorithms similar to the slice method, table look-up method, etc., but anyway, it is necessary to dynamically demonstrate the current situation. The computer is a severe test (here the computer is a workstation with at least 64 cores of memory 128G, home computers do not have to consider).
The above picture shows a two-dimensional hologram. For example, the picture is only a few millimeters in area, so it is enlarged with a CCD. Do you feel disappointed? Can this be called a hologram? But the reality is that this is a true replacement hologram. Increasing the number of lattices (that is, spending more money) can increase the clarity, and using a combination of three primary colors can achieve color, which is achieved, but the effect is far too far from the difference in the video in the movie.
Let's look at the example below.
Can achieve the effect of the map, has used 24 billion pixels ... ...
In fact, the naked-eye 3D dynamic display technology is not only a holographic item, but the effects currently achieved by many other technologies have been commercially available (such as stage and exhibition), and they have been intentionally or unintentionally named in the name of “holographyâ€. But from the perspective of prospects, the tempting technology is the most attractive. Here we come to popularize those pseudo-holographic naked eye devices.
Projector (display) + semi-permeable membrane
In fact, this kind of technology is indistinguishable from the projector + screen projection method that everyone usually sees, except that the curtain is replaced with a translucent film. The key is the translucent film. On the one hand, it is necessary to ensure that some of the light can pass through, and objects behind the curtain can be seen; on the other hand, there must be a certain amount of diffuse reflection, so that the projected pattern can be seen by everyone. In the dark environment, the film is almost invisible, and the projected pattern is like hanging in the air. It is very sci-fi.
Such devices are more common on the stage and exhibitions, and the most widely known is the Hatsune Future Concert. The typical variant of this technology is Li Yuchun's program at the CCTV Spring Festival Gala this year. It is called “45° projection filmâ€. The schematic diagram is as follows:
There is a screen on the ground, and then a 45° tilted semi-transmissive film is set up on the steel frame. In fact, according to the knowledge of the physics of junior high school physics, everyone will understand that using a transflective film as a mirror, then the ground screen What appears on the display is reflected in the viewer's eyes exactly as if it were standing. In the dark environment, the effect is still very amazing.
The following figure shows the construction of the stage when the reflective film is arranged:
Based on this principle, we will continue to consider the improvement of the 45° reflection device. If a similar reflective film or mirror is added at all angles, and the light reflected by each angle, it is exactly what the human eye should see in this position. Didn't it achieve a 360° stereoscopic display?
In reality, such a device is indeed implemented. The projector (or screen) calculates the appearance of objects that should be displayed at different angles, and then sets a high-speed rotating mirror at the center to reflect the light. In this way, no matter what angle people observe, because of the persistence of vision, they will see the true appearance of the object, as if a real object is suspended in midair.
However, the device must be provided with a transparent cover, otherwise the mirror can be thrown out of trouble... This technical effect is actually the closest to the "holographic projection" of a science fiction movie, but it cannot be touched by hand.
Parallax barrier
The other is the special screen that Nintendo 3DS uses. Everyone has the experience of watching 3D movies. Everyone wears a pair of 3D glasses. The cinema provides polarized light. The home is often red, green or red and blue. In fact, in principle, the left and right eye visual signals are isolated and seen separately. Different, certain parallax images produce a three-dimensional effect.
In front of the screen to achieve the isolation of the visual signal of the left and right eye through the naked eye, to use visual barrier technology. In fact, a layer of “barriers†blocking light is added to the front of the LCD screen. The width and position of the design allow the left eye and right eye to receive different light, as shown in the following figure:
In this way, the naked eye realizes the 3D effect that was previously required to wear glasses. Of course, as can be seen from the above figure, this technology places a high demand on the position of the eyeball.
When the music rang and the teacher Zhang Jinlai waved the golden cudgel, there was a feeling of time and space intertwined. The two ends of the golden cudgel were connected to childhood and now, the golden monkey returned, awakening feelings, bursting 3D special effects, giving you a The Monkey King, who enjoys the fog and fog.
How is this special effect achieved?
As early as the award ceremony for the 2014 Billboard Music Awards, this technology was used to "revive" the deceased King Michael Jackson. In the CCTV Spring Festival Gala in 2015, Li Yuchun sang "Sui Xiu" also used a similar technique. What kind of technology is this?
A small globe projected in a set of big bang
The following figure is the SLM array device, it is definitely burning money!
Let's look at the example below.
Can achieve the effect of the map, has used 24 billion pixels ... ...
In fact, the naked-eye 3D dynamic display technology is not only a holographic item, but the effects currently achieved by many other technologies have been commercially available (such as stage and exhibition), and they have been intentionally or unintentionally named in the name of “holographyâ€. But from the perspective of prospects, the tempting technology is the most attractive. Here we come to popularize those pseudo-holographic naked eye devices.
Projector (display) + semi-permeable membrane
The following figure shows the construction of the stage when the reflective film is arranged:
Projector (display) + High-speed turning mirror
The first type of device above does not actually achieve a true stereoscopic display. It is essentially no different from the 2D movie we see. There is actually no stereoscopic effect and the optimal viewing angle is limited, not a 360° panorama. Based on this principle, we will continue to consider the improvement of the 45° reflection device. If a similar reflective film or mirror is added at all angles, and the light reflected by each angle, it is exactly what the human eye should see in this position. Didn't it achieve a 360° stereoscopic display?
In reality, such a device is indeed implemented. The projector (or screen) calculates the appearance of objects that should be displayed at different angles, and then sets a high-speed rotating mirror at the center to reflect the light. In this way, no matter what angle people observe, because of the persistence of vision, they will see the true appearance of the object, as if a real object is suspended in midair.
Parallax barrier
In front of the screen to achieve the isolation of the visual signal of the left and right eye through the naked eye, to use visual barrier technology. In fact, a layer of “barriers†blocking light is added to the front of the LCD screen. The width and position of the design allow the left eye and right eye to receive different light, as shown in the following figure:
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