1. 3D
By Yura

2. What is 3D?
3D means three-dimensional, i.e. something that has width, height and depth (length). Our physical environment is three-dimensional and we move around in 3D every day.

3. Humans are able to perceive the spatial relationship between objects just by looking at them because we have 3D perception, also known as depth perception. As we look around, the retina in each eye forms a two-dimensional image of our surroundings and our brain processes these two images into a 3D visual experience.

4. Humans use a number of tools for depth perception.
Stereoscopic vision

5. Parallax

6. Aerial perspective

7. 2D Film & Video
A traditional 2-D video image has width and height but technically it has no depth, i.e. everything in the image is presented at the same distance from the viewer. Still, the viewer does perceive the image as three-dimensional by subconsciously using the techniques listed above .

8. Common display methods of 3D:
Anaglyphic images

9. Polarized light system

10. Active shutter system

11. Stereogram
An optical illusion of depth created from flat, two-dimensional image or images. Originally, stereogram referred to a pair of stereo images which could be viewed using a stereoscope.

12. To view the image cross your eyes until four images appear, then allow the images to converge to a set of three, focusing on the centre image.

13. Stereograms were re-popularized by the creation of autostereograms on computers, wherein a 3D image is hidden in a single 2D image, until the viewer focuses the eyes correctly. The Magic Eye series is a popular example of this.
Salvador Dalí created some impressive stereograms in his exploration in a variety of optical illusions.

16. 3D Film
  A motion picture that enhances the illusion of depth perception. Derived from stereoscopic photography, a special motion picture camera system is used to record the images as seen from two perspectives (or computer-generated imagery generates the two perspectives), and special projection hardware and/or eyewear are used to provide the illusion of depth when viewing the film.

17. 3-D films have existed in some form since the 1950s, but had been largely relegated to a niche in the motion picture industry because of the costly hardware and processes required to produce and display a 3-D film, and the lack of a standardized format for all segments of the entertainment business. Nonetheless, 3-D films were prominently featured in the 1950s in American cinema, and later experienced a worldwide resurgence in the 1980s and '90s driven by IMAX high-end theaters and Disney themed-venues. 3-D films became more and more successful throughout 2000–10, culminating in the unprecedented success of 3-D presentations of Avatar in December 2009 and January 2010.

21. 3D Film & Video
3D video adds stereoscopic vision, meaning that two separate images are shown simultaneously, one to each eye. This presents enormous technical problems which is why there is still no perfect system almost 100 years since the first 3D movie was made.