Jennifer Rohrs lives in Boston, MA, and she just completed her sophomore year at the University of Southern California, majoring in biomedical engineering. After graduation, she hopes to work in the pharmaceutical industry researching and developing drugs.
Image depth is created by three processes: layering, line perspective, and binocular stereoscopy. The first two are most effective in creating 2D paintings while binocular stereoscopy is used in 3D media today. Stereoscopy employs the same principles as natural binocular vision by layering two slightly different images, which will then be separated for each eye, on one screen. There are two types of technologies used to separate these film images so that each eye only sees one image. The first technology involves polarized lenses, which restrict the angles of light that can pass through them. This allows for each image to be viewed through different polarized lenses. The other type of technology is the active shutter glasses, which pass frames of images in sequence. The lenses of the glasses flicker between black and clear at the same rate, so that each eye only sees every other frame. These technologies are used in a variety of media today, such as film which is currently the most popular from of 3D entertainment. Movies like Avatar have helped to improve both the technology and public awareness of 3D media. Other forms of entertainment such as video games have begun to adapt 3D technology as well. A variety of gaming consoles support 3D games that can be played on 3D televisions or 3D computers. 3D televisions use active shutter glasses and are the most expensive form of three dimensional media. The future of these televisions lies in the development of networks with continuous 3D content. If these televisions become more prevalent and popular, the next step in entertainment will be to incorporate the senses of touch and smell into 4D home systems.
Imagine that the window in your living room looked out to a whole new planet. That is exactly what happens in James Cameron’s 3D movie Avatar made available on Blu-ray. With the progression of 3D media, home entertainment is transitioning from a flat, out-of-reach picture to a realistic, three-dimensional portal.
Advancements in digital video imaging and screening technology have made 3D entertainment a reality. The equipment for viewing images uses either polarized glasses, which skew the light at different angles to overlay two images; or shutter glasses, which close each lens in rapid succession so that only one eye can see at a time. The media that uses 3D imaging is also very diverse. The most popular outlets right now are film, video games, and television, each of which has its own specific technology and equipment. Even with these exciting improvements, however, research in the entertainment industry has not stopped. 4D systems, another stage in the entertainment industry that is quickly approaching, use 3D viewing equipment as well as new technologies. The 4D systems will someday transform a regular living room into an amusement park ride.
Depth and Stereoscopy
There are three main processes used to create depth in paintings: layers, line perspective, and binocular stereoscopy The first two are the most simple for use in media. Layering occurs when objects are placed on top of each other to give the impression that one is positioned in front of another. On the other hand, line perspective uses the idea of a main point of convergence in the distance. As distant objects get closer to this central point they become smaller and smaller in comparison to the objects that are meant to be closer to the viewer. These methods cannot compare to the flexibility and realism of today’s use of stereoscopy, or binocular imaging, the third method of viewing depth.
Most people use binocular vision every day to understand depth and distance. When you look at an object, you are actually seeing two different images of it. Each eye gives a slightly different viewpoint, but both share a single point of focus. The brain interprets those images together, layers them on top of each other, and allow us to distinguish depth.
Stereoscopy, technology for viewing images in three dimensions, mimics our natural binocular vision by utilizing two cameras analogous to two eyes . This method was originally used as a way to view photographs in three dimensions by capturing two pictures of the same object at slightly different angles and placing them in a specialized viewer. This process was soon adapted to motion picture; however, the expensive and highly specialized screens, projectors, and other equipment necessary to show these realistic 3D films prevented them from becoming widespread until recent times. Today, as technology becomes more advanced and prevalent, the public’s desire for life-like interactive media has spurred 3D technology ahead.
Today’s 3D films use two cameras placed a few inches apart, the same distance between human eyes, to capture images of the target that will be viewed in 3D. These two camera images are laid on top of each other on a flat screen. However, when you look at the screen your two eyes each give a separate image of the screen. This means that there are 4 images of the target being interpreted by the brain. The brain can only interpret two of these images, one by each eye, at a time. Without an added method to combine these images, you can only see a blurred pair of 2D overlaid images on the screen. To correct this problem, the camera images need to be skewed using polarization or shutter sequencing technology. These techniques attempt to separate the dual laid image so that each eye only “sees” one of them. If each eye sees a different image of the target, then the brain will be able to interpret the target image in three dimensions, the same way it can interpret a person’s surroundings.
Polarization involves oscillations of an object at a particular angle (see Fig. 1). Polarized materials restrict which oscillations, or angles, of light waves are able to pass through them. Polarized glasses can use filters for horizontal and vertical or clockwise and counterclockwise light wave orientations. Stereoscopy traditionally uses two projectors pointed at the same screen so that the images overlap. The left projector uses a polarized filter with oscillations at a particular angle, while the right projector uses a filter with oscillations that are perpendicular to the left projector’s. The lenses of the glasses contain filters that are polarized at the same angle so that each eye can only see the light rays from the image of one projector. This allows each eye to view only one picture even though both images have been overlapped on a single screen. The polarized lenses ensure that the light waves are passing through at particular angles so that each image can pass through only one of the polarized lenses in the glasses. However, when these light waves hit the screen, there is a possibility that they could lose some energy in the impact, thus changing their orientation. In order to prevent this from happening, a special projection screen called the silver screen must be used. The silver screen, which is made from a different material than a regular, white, projection screen, prevents the light waves from losing energy or shifting direction when they reflect off the screen .
LCD shutter glasses
LCD shutter glasses (see Fig. 2), otherwise known as active glasses, are a pair of battery powered, automated glasses worn by viewers. The lenses contain a liquid crystal which is clear in its regular liquid form but, when an electric current is applied, the molecules in the liquid align in a crystalline structure that is opaque black . The screen shows images for the left and right eye, one at a time, in rapid succession. A sensor on the screen sends a signal to the glasses to coordinate them with the left and right frame sequence. This sensor triggers a voltage that turns the right lens black when the screen shows the image for the left eye and vice-versa. The images pass so quickly, with each frame lasting 1/120th of a second, that the brain does not have time to interpret each image individually. This allows us to see a smooth moving 3D image. A drawback for shutter glasses is that they can cause mild headaches from the continuous flashing . These glasses do not require a special screen, only a system with a fast enough refresh rate to handle the high frame rate. Therefore, these screens can be used to play either 2D or 3D media.
Media and Equipment
There are currently three main outlets of 3D technology in today’s economy: film, videogames, and television. Film is leading the way in the new 3D era and is closely followed by videogames, which allow for easy 3D conversion through simple changes in computer coding of the digital media. 3D televisions are expensive and still very new to the public; with no 3D programming currently available outside of film and video games, the future of 3D television lies in the success of the other two types of media. The current popularity of 3D films suggests that in the next decade it is likely that the majority of American homes will hold 3D theaters.
Film is currently the most common and successful channel for 3D technology. This is in part due to the ability of large theaters to purchase the expensive equipment necessary for 3D screenings.
Most movie theaters that show 3D films use polarized glasses since active glasses are very expensive and require too much energy to permit an efficient viewing platform in large public arenas. To use polarized glasses, the theater must invest in the specialized silver screens and 3D projectors. There are two types of projector systems that can be used. The first is a system of two projectors, each with a different polarized filter over the lens. The projectors are positioned next to each other and both are aimed directly at the center of the screen. This system is accompanied by many problems, including difficulty angling the projectors at the correct angles and glitches between timing of the two machines. Recently, however, a new projector called the Sony RealD XLS was invented to fix these problems. This projector is similar to the projectors for active glasses. The frames for each eye are placed in series on one roll of film. The projector has a mechanism over the lens that flips between the two polarized filters at the same rate as the frames pass. Because there is only one filter over each frame, only one eye is able to see through a single polarized glass. The frames pass so quickly that the brain interprets them as a single 3D movie . The high demand and increased cost of equipment to show these 3D movies makes 3D films more expensive to the audience than 2D films. For example, a 3D movie at Los Angeles’ Regal L.A. Live Stadium 14 costs $15.50, while a regular movie at that location costs $12.00.
James Cameron’s new movie Avatar has been called the turning point for 3D technology. For this film he used both computer graphic technology, like that used in videogames, as well as a new 3D camera created just for his film . This camera uses two lenses and still requires the use of polarized glasses, like traditional stereoscopic cameras. However, advancements in digital technology allow more information to be stored in a smaller space, thus creating smaller cameras that allow lenses to be positioned closer together. Motorized mechanisms in each camera allow the lenses to move independently, just as our pupils do. This camera’s similarity to the human eye gives it the ability to follow a main focal point and capture a more realistic 3D image . It will depict a real, physical world, instead of the flat layers or unrealistic, shuttering images in older 3D films. This new technology is a method of bringing the audience into the storyline, enhancing the experience and making even the most alien of planets, like Pandora in Avatar, come to life in the theater.
Video games have a great potential to utilize 3D technology. Computerized animation enables many current games to be converted into 3D versions since these games are designed to be viewed at various angles . Because video games are digitally created, a computer code is programmed to reposition the viewpoint and sequence the images to create a 3D projection adaptable to active glasses technology.
The playful aspect of the gaming media can be very rewarding. For example, an obstacle flying out toward you would be an entertaining addition to a lighthearted game such as Mario Kart. In video games, these distractions can be viewed as added challenges that actually enhance game play. 3D video games also provide a deeper feeling of interaction because the user can control a world that looks like his or her own.
Currently, Sony Computer Enhancement is striving to become the leader in the 3D gaming systems through the video console Sony PlayStation 3 (PS3). It is currently the only company to offer software updates that enable the games to appear in 3D. Sony is also working on a second update to enable PS3 to be played on 3D Blu-rays . These advancements will help to lower the cost of 3D entertainment systems as well as promote new 3D technology to the wide community of PlayStation users. In order to gain a foothold in this rapidly increasing market, many other gaming companies are sure to update their systems for 3D. Since these systems display the games on television screens, if 3D videogames continue to excel, they could quite possibly be the tipping point for the success of 3D televisions.
As 3D movies come out on DVD and Blu-ray, it is likely that people will want the same three dimensional experience in their homes. This will encourage Americans to embrace 3D televisions. New television screens, video players, and glasses have recently appeared in commercials throughout the nation, including Samsung’s new 3D television screen, which was advertised in valuable commercial space during the Academy Awards on March 7, 2010. All the attention received by Avatar as well as other 3D films released for home viewing on Blu-ray, including the Pixar film Up or Focus Feature’s Coraline, proves that the majority of the public enjoys 3D. However, is it just a fad, or will it last long enough to sell the multi-thousand dollar 3D TV systems?
The main concern about 3D television is the high price of the equipment. Most companies have chosen to use the LCD shutter glass technology for home use so that the TV screens can play both 2D and 3D images . The LCD shutter glasses require sensors that interact with the TV and Blu-ray player to signal the glasses to close and open certain lenses. Since each pair of glasses is sold separately at $70 per pair, purchasing these glasses can be very costly, especially for large families . As described above, screens that work with active glasses need very high refresh rates so that the picture does not appear choppy. The smallest refresh rate necessary to play 3D content is 120Hz, which most new HD televisions can handle. These TVs are “3D-capable,” but not “3D-ready,” meaning that they are able to play 3D material but still need extra hardware, including the sensors for the active glasses, to allow the system to work . Newer technology has enabled refresh rates of up to 240Hz, which are used in 3D-ready televisions available on the market today. These TVs offer higher quality 3D viewing, and newer 3D Blu-rays may only be compatible with these specific televisions. This means that in most cases, a new TV screen would also have to be purchased in order to use the 3D Blu-ray. Purchasing all this equipment can lead to a cost of $4,000 to transform your home entertainment system from a regular television to a real-life window into the movie world.
Another obstacle that 3D TV has to overcome is content limitation. Right now the only form of 3D media is the three dimensional blu-ray movies, which are limited in number. As an incentive aimed at male consumer, ESPN started a new network to show sporting events in 3D. However, when there is no 3D game playing, the network channel will appear black on the screen. IMAX, the pioneer of 3D entertainment, is teaming up with Sony Entertainment and Discovery Channel to create their own 3D network. With only few prospects for continuous 3D programming, the fate of the 3D TV is left in a paradox of sorts: 3D TVs will not sell without continuous programming, but there is no incentive to develop 3D programming if no one has the 3D televisions to watch such programs.
The next step to enhance 3D technology is 4D entertainment. 4D incorporates other senses, besides just hearing and sight, into the entertainment experience. They do this through fans that blow wind or expel smells and seats that move . Amusement parks world-wide already use this technology to enhance the experience of film. Attractions like “A Bug’s Life” in Disney World’s Animal Kingdom in Orlando, FL and even the MOM (motion odyssey movie) in select Jordan’s Furniture stores are examples of 4D entertainment. These “rides” bring the audience into the movie in a whole new way, not only by showing a 3D window into the film, but also by pushing the audience head first into it. On the ride Soarin’ over California at Disney’s California Adventure in Los Angles, CA, patrons’ seats move like a virtual airplane while they feel the wind on their faces and the spray of the sea as they fly across the whole state of California.
4D has not yet expanded past highly used public arenas, but if the expansion of 3D entertainment continues, it will only be a matter of time before 4D technology enters people’s homes. Specialized motion sensors can be placed on fans next to the television and hydraulic couches can send the viewer bouncing over speed bumps and crashing around corners during movie chase scenes. These advancements are just around the corner and are sure to be followed by an unending stream of entertainment technology for the American public.
-  Sensio. “History of 3D.” Internet: http://www.sensio.tv/en/3d/3d_history/default.3d, March 2010.
-  Rainbow Symphony, Inc. “Polarized 3D Glasses.” 3D Glasses. Internet: http://www.rainbowsymphony.com/index.html, March 20, 2010.
-  T. Engdahl. “3D glasses and other 3D display devices.” ePanorama.net. Internet: http://www.epanorama.net/index.php, 2009.
-  J. Biggs. “The Plusses, and Oddities, of 3-D TV.” New York Times, February 3, 2010.
-  J. Slater. “The Dolby solution to Digital 3D.” Cinema Technology, March 2008.
-  E. Wrenn. “Avatar: How James Cameron’s 3D film could change the face of cinema forever.” Associate Newspapers Ltd, August 26, 2009.
-  “James Cameron Stereoscopic 3D Camera.” YouTube. Internet: http://www.youtube.com/watch?v=2squ9HDuBeI&feature=player_embedded#, February 8, 2010.
-  “3D Digital Camera.” YouTube. Internet: http://www.youtube.com/watch?v=t5H-vDvPIuo&feature=related, April 30, 2010.
-  C. Faylor. “Sony Talks PlayStation 3 3D Update, Requirements.” ShackNews. Internet: http://www.shacknews.com/onearticle.x/61871, January 8, 2010.
-  B. Patterson. “JVC shows off 3D TVs with cheaper, polarized 3D glasses.” Yahoo Tech. Internet: http://tech.yahoo.com/blog/patterson/63731, January 12, 2010.
-  A. Pollard. “3D TV FAQ.” Crutchfield. Internet: http://www.crutchfield.com/learn/HDTV/3D-TV-FAQ.html, April 8, 2010.
-  “BestBuy.” Internet: http://www.bestbuy.com/.
-  J. Broek. “3D or not 2D, That is the Question.” Architecture. Internet: http://jeanricardbroek-architect.blogspot.com/2008_06_01_archive.html, June 25, 2008.
-  C. Demerjian. “Nvidia picks the wrong 3D glasses technology.” [ilThe Inquirer[/i], Incisive Media Investments Limited, January 10, 2010.
-  G. Dickson. “CES 2010: ESPN Details 3D Plans.” Broadcasting & Cable. New Bay Media, January 7, 2010.
-  L. Edwards. “Active Shutter 3D Technology for HDTV.” Physorg.com. Internet: http://www.physorg.com/news173082582.html, September 25, 2009.
-  “Full HD3D Live in It!” Panasonic: Ideas For Life. Internet: http://panasonic.com/3d/, February 28, 2010.
-  L.R. Harris and M. Jenkin. Vision and Action. New York: Cambridge University Press, 1998.
-  “How to make 3D anaglyph images using Photoshop.” YouTube. Internet: http://www.youtube.com/watch?v=8TyzhHpF-UM, December 30, 2008.
-  C. Iozzio. “Hands On: Fujifilm Real 3D W1 Digital Camera.” Popular Science. September 30, 2009.
-  D. Lyons. “TV’s Next Dimension: Why Goofy Glasses are in Your Future.” Newsweek, August 31, 2009.
-  W. Matusik and H. Pfister. “3D TV: a scalable system for real-time acquisition, transmission, and autostereoscopic display of dynamic scenes.” AMC Transactions on Graphics (TOG), Vol. 23.3, pp. 814-824, 2004.
-  “NVIDIA GeForce 3D Vision.” YouTube. Internet: http://www.youtube.com/watch?v=gLn0onkR8Ag&feature=related, July 17, 2009.
-  D. Reisinger. “First dedicated 3D networks coming to TV.” CNET News. Internet: http://news.cnet.com/8301-13506_3-10425553-17.html, January 25, 2010.
-  E. Sofge. “Why 3D Doesn’t Work for TV, But Is Great for Gaming: Analysis.” Hearst Electronic Products. January 2010.
-  S. Steinberg. “3D TV: Is the World Really Ready to Upgrade?” Digital Trends. Internet: http://www.digitaltrends.com, February 28, 2010.
-  B. Stelter and B. Stone. “Television Begins a Push into the 3rd Dimension.” New York Times, January 5, 2010.
-  “The Sims franchise celebrates its fifth anniversary and continues to break records.” Business Wire. Internet: http://www.tmcnet.com/usubmit/2005/feb/1114806.htm, February 7, 2005.
-  “X-4D Demostration.” YouTube. Internet: http://www.youtube.com/watch?v=NjHIJpdkBSE&feature=related.