History
It was Sir Charles Wheatstone who in 1833 first came up with the idea of presenting slightly different images to the two eyes using a device he called a reflecting mirror stereoscope. When viewed stereoscopically, he showed that the two images are combined in the brain to produce 3-D depth perception. The invention of the Brewster Stereoscope by the Scottish scientist Sir David Brewster in 1849 provided a template for all later stereoscopes. This in turn stimulated the mass production of stereo photography which flourished alongside mono-photography. Stereo photography peaked around the turn of the century and went out of fashion as movies increased in popularity.The stereoscope was improved by Louis Jules Duboscq and a famous picture of Queen Victoria was displayed at The Great Exhibition in 1851. In 1855 the Kinematoscope was invented, i.e., the stereo animation camera. The first anaglyph (use of red-and-blue glasses,invented by L.D. DuHaron) movie was produced in 1915 and in 1922 the first public 3D movie was displayed. Stereoscopic 3D television was demonstrated for the first time on August 10, 1928, by John Logie Baird in his company's premises at 133 Long Acre, London. Baird pioneered a variety of 3D television systems using electro-mechanical and cathode-ray tube techniques. In 1935 the first 3D color movie was produced. By the Second World War, stereoscopic 3D still cameras for personal use were already fairly common.
In the fifties, when TV became popular in the United States, many 3D movies were produced. The first such movie was Bwana Devil from United Artists that could be seen all across the US in 1952. One year later, in 1953, came the 3D movie House of Wax which also featured stereophonic sound. Alfred Hitchcock originally made his film Dial M for Murder in 3D, but for the purpose of maximizing profits the movie was released in 2D because not all cinemas were able to display 3D films. The Soviet Union also developed 3D films, with Robinzon Kruzo being their first full-length 3D movie in 1946.
Subsequently, television stations started airing 3D serials in 2009 based on the same technology as 3D movies. In 2010, video games began to utilize 3D TVs as a new way to play the games.
There are several techniques to produce and display 3D moving pictures. The basic requirement is to display offset images that are filtered separately to the left and right eye. Two strategies have been used to accomplish this: have the viewer wear eyeglasses to filter the separate offset images to each eye, or have the lightsource split the images directionally into the viewer's eyes (no glasses required). Common 3D display technology for projecting stereoscopic image pairs to the viewer include:[4]
Technologies
- With lenses:
- Anaglyphic 3D (with passive red-cyan lenses)
- Polarization 3D (with passive polarized lenses)
- Alternate-frame sequencing (with active shutter lenses)
- Head-mounted display (with a separate display positioned in front of each eye, and lenses used primarily to relax eye focus)
- Without lenses: Autostereoscopic displays, sometimes referred to commercially as Auto 3D.
Various other display techniques have been described, such as holography, volumetric display and the Pulfrich effect, which was used by Doctor Who for Dimensions in Time in 1993, by 3rd Rock From The Sun in 1997, and by the Discovery Channel's Shark Week in 2000, among others. Real-Time 3D TV (Youtube video) is essentially a form of autostereoscopic display.
Stereoscopy is the most widely accepted method for capturing and delivering 3D video. It involves capturing stereo pairs in a two-view setup, with cameras mounted side by side, separated by the same distance as between a person's pupils. If we imagine projecting an object point in a scene along the line-of-sight (for each eye, in turn) to a flat background screen, we may describe the location of this point mathematically using simple algebra. In rectangular coordinates with the screen lying in the Y-Z plane (the Z axis upward and the Y axis to the right) and the viewer centered along the X axis, we find that the screen coordinates are simply the sum of two terms, one accounting for perspective and the other for binocular shift. Perspective modifies the Z and Y coordinates of the object point by a factor of D/(D-x), while binocular shift contributes an additional term (to the Y coordinate only) of s*x/(2*(D-x)), where D is the distance from the selected system origin to the viewer (right between the eyes), s is the eye separation (about 7 centimeters), and x is the true x coordinate of the object point. The binocular shift is positive for the left-eye-view and negative for the right-eye-view. For very distant object points, it is obvious that the eyes will be looking along the same line of sight. For very near objects, the eyes may become excessively "cross-eyed". However, for scenes in the greater portion of the field of view, a realistic image is readily achieved by superposition of the left and right images (using the polarization method or synchronized shutter-lens method) provided the viewer isn't too near the screen and the left and right images are correctly positioned on the screen. Digital technology has largely eliminated inaccurate superposition that was a common problem during the era of traditional stereoscopic films.
Multi-view capture uses arrays of many cameras to capture a 3D scene through multiple independent video streams. Plenoptic cameras, which capture the light field of a scene, can also be used to capture multiple views with a single main lens. Depending on the camera setup, the resulting views can either be displayed on multi-view displays, or passed for further image processing.
After capture, stereo or multi-view image data can be processed to extract 2D plus depth information for each view, effectively creating a device-independent representation of the original 3D scene. This data can be used to aid inter-view image compression or to generate stereoscopic pairs for multiple different view angles and screen sizes.
2D plus depth processing can be used to recreate 3D scenes even from a single view and convert legacy film and video material to a 3D look, though a convincing effect is harder to achieve and the resulting image will likely look like a cardboard miniature.
3D-ready TV sets
3D-ready TV sets are those that can operate in 3D mode (in addition to regular 2D mode), in conjunction with a set-top-box and LCD shutter glasses, where the TV tells the glasses which eye should see the image being exhibited at the moment, creating a stereoscopic image. These TV sets usually support HDMI 1.4 and (if an LCD Television) a minimum (input and output) refresh rate of 120 Hz; glasses may be sold separately.Panasonic already has several sets in the market (like the Panasonic Viera TC-P50VT200 which are 3D capable and come shipped with glasses. It has a retail price of approximately US$2,500. The Samsung UN46C7000 46-Inch 3D TV can be purchased for US$2,000.00 or less. There are numerous, relatively inexpensive models available from a number of manufacturers already in the summer of 2010.
Mitsubishi and Samsung utilize DLP technology from Texas Instruments. As of January 2010, Samsung, LG, Toshiba, Sony, and Panasonic all had plans to introduce 3D capabilities (mostly in higher-end models) in TVs available sometime in 2010. 3D Blu-ray players went on sale in 2010, and Sky began 3D broadcasts in the UK on 3 April 2010. DirecTV broadcasts began with the 2010 FIFA World Cup in June 2010. Samsung began selling the UN55C7000, its first 3D ready TV, late in February 2010.
Philips was developing 3D television sets that would be available for the consumer market by about 2011 without the need for special glasses (autostereoscopy). However it was canceled due to the slow adaptation of customers going from 2D to 3D.
In August 2010, Toshiba announced plans to bring a range of autosteroscopic TVs to market by the end of the year.
The Chinese manufacturer TCL Corporation has developed a 42-inch (110 cm) LCD 3D TV called the TD-42F, which is currently available in China. This model uses a lenticular system and does not require any special glasses (autostereoscopy). It currently sells for approximately $20,000. The biggest problem using lenticular lens as used also by Philip Dimenco is the sharpness of the display. Although we use 4K (4 times of Full HD TV), the image we saw was coarse in appearance due to lenticular lens technology required to refract the left and right images for each eye, so the technology used is certainly better suited for non-stationary viewing. The border around objects in the screen tended to shift quickly and blur.
LG, Samsung, Sony & Philips intend to increase their 3D TV offering with plans to make 3D TV sales account for over 50% of their respective TV distribution offering by 2012. It is expected that the screens will use a mixture of technologies until there is standardisation across the industry. Samsung offers the LED 7000, LCD 750, PDP 7000 TV sets and the Blu-ray 6900.
On June 9, 2010, Panasonic unveiled a 152 inches (390 cm) 3D-capable TV (the largest so far) that will go on sale within 2010. The TV, which is the size of about nine 50-inch TVs, will cost more than 50 million yen (US$576,000).
Full 3D TV sets include Panasonic Full HD 3D (1920X1080 p, this is, 2 Mp; and 60 Hz).
Toshiba has shown 20 and 12 inch autostereoscopic (this is, glassesfree) LCD 3D TV sets for commercial launch, with a 1280X720 resolution. By systematically aligning pixels and adopting a perpendicular lenticular sheet, Toshiba´s LCD panel eliminates blurring, or the vertical wave pattern (caused by interference in the display cycle) that plagues other autostereoscopic 3-D technologies. The viewing angle is about 40ยบ, doubling the previous approaches. Toshiba's glasses free 3D TV does suffer initial limitations such as viewing distance and cost, the 12 inch model will sell for roughly $1400. Toshiba are expected to deliver their glasses free 3D TV on a global scale by 2015.
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