Stereoscopic technology

Stereoscopic technology

How it doing

All the technology of 3D- video can be reduced to one principle: the video taken from two positions separated by a distance equal to the average distance between the centers of the eyes (60 - 70 mm). As a rule , remove or two cameras attached to the special holder (Fig. 1) , or a special 3D- camera with two lenses.

Стерео камеры

Fig.1. Tripod for a stereo camera

In the case of creating an animated film , just do a double rendering of the scene - with two cameras corresponding viewer's eyes .

There are also the technology of three-dimensional image by distorting the original video frames to obtain 2x frames corresponding to the left and right cameras.

How we see it
Over a century of development stereokinematografa we got a few technologies that allow us to watch videos in 3D.
It should be noted that the stereoscopic technology - that whereby we can see on the screen is really three-dimensional image is often replaced by the concept of 3D- technology , by which initially involves the entire computer graphics, which are created with the help of animated movies and special effects .
According to the established tradition in speech , in the future will be understood by 3D- video is just a stereoscopic video.
Currently in the world develops several stereoscopic technologies, each of which has its pros and cons . However, in each of them , as in the technology of 3D- video, laid the fundamental method of image is carried separately for each eye.

Anaglyph technology

Fig.2. The operating principle of anaglyph image

To screen for viewing projected two images superimposed on each other : one in red tones , the other - in blue . Points must also have a glass of the same color. When this blue polupara seen through blue glass and red seen through the red .
There are other types polupar :
red-cyan / red - blue
green-magenta / green - purple
yellow-blue / green - purple

Technology Benefits : low cost , ease of use - no special monitor or projector .
Disadvantages: often have color irregularity , fatigue eye frames out of sync , it is necessary to demonstrate the video projector 2 .
Stereotehnologiya anaglyph ( color separation ) is actively used in 3D pictures, to showcase short films at exhibitions etc. In the movie, hardly used and replaced by more modern .

Technology Infitec ( commercial name of Dolby 3D)


Technology is an evolution of technology anaglyphs .
Based on the color separation within the range of colors ( color waves ) (Infitec- comes from the words «Interference filter technology» - technologies associated with the interference effect ) . For left and right eyes using different colors (as in anaglyph technology ) , but in this 3D technology division does not occur in two colors , and individual strips within the spectrum of colors, which allows for much better stereo quality .
This also applies stereotehnologies glasses with filters and their structures were difficult because they share a whole range of colors. These glasses have a relatively high cost, and that is one of the main disadvantages of technology.
 
However, in comparison with the polarization technology ( which will be discussed below) , this method allows you to save on the cost of the screen (not required silvered or aluminized screen ) which is why the technology has found wide application in 3D cinemas.

polarization technology


Based on the polarization of light waves separation . When polarized light waves , they oscillate in a direction transverse to their proliferation and appropriate filters are able to transmit light with a specific angle of inclination of the plane of polarization. For example, the linear polarization filter for the left eye is polarized at an angle of 45 °, to the right - 135 °. They are polarized perpendicular to each other , which means that one misses "his" half light waves. Thus, polarized perpendicular to the stream direction for the left and right eyes , and the filter ( polarized glasses ), for each of them transmits only the required image since they are installed in a polarizing lens that transmit only light rays that have polarization direction , parallel to the polarization direction of the spectacle lens .
Technology Benefits : High quality 3D- effect , the use of a projection system for a large number of viewers , the most convenient solution for prolonged viewing 3D- stereo.
Disadvantages: slight imperfections in the separation of images due to the scattering properties of the screen , 3D- stereoscopic technology equipment requires space to accommodate the complexity of the installation and configuration of equipment, a special 3D- screen .
Application: 3D- Cinema , bulk 3D- displays, shows, exhibitions and activities for science and education for complex projects .

Polarization technology used in theaters and IMAX 3D format RealD.

In IMAX 3D technology uses linear polarization . In RealD 3D technology uses circular polarization of light. This technology is similar to the IMAX with the difference that the circular polarization instead of linear (IMAX 3D) stereo allows you to save and avoid ghosting when small lateral tilt of the head .

The gate technology

This technology uses an alternate image display , designed for each eye and also alternately darkening eyeglass lens , so that each eye sees a turn -only image of him . Due to the inertia of the human eye ( the delay of our visual reaction is relatively real moving object , and the smoothing effect it falls ) , an illusion of a solid three-dimensional image .


Pluses shutter : high image quality , ease of installation and configuration support for many manufacturers , availability, the best solution for the home, the ability to integrate complex 3D- systems.
Disadvantages: special requirements for 3D- equipment (high frequency 3D-monitora/3D-proektora - 120 Hz), expensive 3D- glasses, is inconvenient for mass events.
 

Lenticular ( micro ) technology


Does not require special glasses , but also based on the principle of stereoscopy for monitors and televisions. Images for each eye are separated with a special film applied to the monitor screen and possessing certain optical properties. Microlenses refract the image at different angles so that a person in a particular viewing area receives different images for the left and right eyes.
The technology is still in its infancy , because the generated 3D- effect is obtained when the person in a particular viewing area . Nevertheless, experts predict the technology will be used in such crowded places , such as : railway stations, supermarkets, exhibitions, etc.