3D Movies and the 3DS

From Andrew:

In general, there are 3 different techniques for 3D images.

Anaglyph systems use red and cyan glasses that block either red light or green and blue light. The biggest advantage of anaglyph images is that since it relies only on color, any color TV or computer screen can display them[1]. 3D movies used to be widely available for home viewing using an anaglyph system, and Minecraft has a setting to turn on 3D anaglyphs. However, since anaglyphs use color to distinguish between the eyes, a portion of color detail[1].

Polarized Systems use left-handed and right-handed circularly polarized light (RealD) or horizontal and vertical linearly polarized light (IMAX) and glasses that filter them out. This allows fully colored images to reach both eyes, producing a more detailed image. The definite advantage is that there is no quality loss in the system. However, normal televisions and computer monitors can’t display polarized 3D, and the projectors and screens that allow for it are expensive [2]; however, 3D TV’s exist that use polarized systems to display 3D images [3].

Active-Shutter systems alternate quickly between two perspectives, and the glasses have LCD shutters that open and close in a synchronized pattern with the display. The advantage is that it produces the sharpest images of the three. Once again, however, these glasses are expensive, and  some users will notice the flicker in the refresh rate [3].

All three of these are significant technologies for 3D viewing, but what about the 3DS? It doesn’t have glasses at all.

Image from http://electronics.howstuffworks.com/nintendo-3ds5.htm. Retrieved September 28, 2014.

Image from http://electronics.howstuffworks.com/nintendo-3ds5.htm. Retrieved September 28, 2014.

The screen of the 3DS has a layer on top of it, called the parallax barrier, which directs light so that it appears 3D. The parallax barrier is an LCD barrier which can block light to restrict viewing. When you turn the 3D off on the 3DS, this screen becomes completely transparent. When you move the switch, the placement and width of the blocking zones to change the depth of 3D. This technology, however, would be completely unsuitable for television, since it has a very limited viewing angle [4].

 

Sources:

[1]. 3DUniversity.Net. “Anaglyph.” 3D@Home Consortium/International 3D Society, n.d. http://www.3duniversity.net/page.aspx?page=233, September 28, 2014.

[2]. Martin Bromley. “Passive 3D Using Polarization.” 3D TV Technology, n.d. http://www.3dtvtechnology.org.uk/passive-3d, September 28, 2014.

[3]. Steve May. “Active Shutter vs Passive 3D TV: which is best?” TechRadar TVs, May 24, 2011. http://www.techradar.com/us/news/television/active-shutter-vs-passive-3d-tv-which-is-best-958717, September 28, 2014.

[4]. Jonathan Strickland. “How the Nintendo 3DS Works.” HowStuffWorks, n.d. http://electronics.howstuffworks.com/nintendo-3ds.htm, September 28, 2014.

Featured Image from http://www.3dtvtechnology.org.uk/polarization. Retrieved September 28, 2014.

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Technology: Holography

From Andrew:

In the movie, there are some fairly impressive displays of holography. In reality, holography is quite possible, although not to show generated images. Holograms are made by shining a laser through a beam splitter and directing one beam directly to the film and the other beam to the object of which a hologram should be made, and then to the holographic film, as shown in the picture at left. According to HowStuffWorks, the process is as follows:

  1. The laser points at the beam splitter, which divides the beam of light into two parts.
  2. Mirrors direct the paths of these two beams so that they hit their intended targets.
  3. Each of the two beams passes through a diverging lens and becomes a wide swath of light rather than a narrow beam.
  4. One beam, the object beam, reflects off of the object and onto the photographic emulsion.
  5. The other beam, the reference beam, hits the emulsion without reflecting off of anything other than a mirror.[1]

When the hologram is to be displayed, it is then necessary to make another setup. Shining a monochrome light at the film makes the object appear in the same spot relative to the film where the object was initially[1]. In theory, it would be possible to construct holographs from raw light, but this technology is not fully developed.

Sources:
[1]. Tracy Wilson. “How Holograms Work.” HowStuffWorks, 2007. http://science.howstuffworks.com/hologram.htm, September 21, 2014.