CONTENTS*INTRODUCTION*BASICS OF 3D TV*ARCHITECTURE OF 3D TV*TECHNOLOGIES PRESENLTY USED*MULTIVIEW AUTO STEREOSCOPIC DISPLAY*3D VIEWERS*APPLICATION OF 3D TV*DISADVANTAGES*CONCLUSION*REFERENCE
INTRODUCTION* At First films were silent, then sound was added.* Cinema and television were initially black and white,then colour tv was introduced.* Computer imaging and digital special effects havebeen the latest major novelty.* Nowadays markets are flooded with HDTV,LCD andPlasma TV’s* 3D TV is expected to be next revolution in theTV industry
BASICS OF 3D TV*BINOCULAR PARALLAX: Binocular parallax refers to theability of the eyes to see a solid object and a continuous surfacebehind that object even though the eyes see two different views.*MOTION PARALLAX: It means information at the retinacaused by relative movement of objects as the observer moves tothe side(or his head move sideways)*DEPTH PERCEPTION: It allows the beholder to accuratelygauge the distance to an object. It is the visual ability to perceivethe world in three dimensions.
StereoscopeIt is an optical device for creating stereoscopic(or threedimensional) effects from flat(two dimensional) images.D. Brewster first constructed the stereoscope in 1844.
*Stereographic images:It means two pictures taken with a time separationthat are then arranged to be viewed simultaneously.*Holographic images:A luminous, 3D, transparent coloured andnonmaterial image appearing out of a 2D medium,called a hologram.
ARCHITECTURE OF 3D TV TECHNOLOGY*Acquisition*Transmission & display
*AcquisitionThe acquisition stage consists of an array of thehardware synchronizes cameras.*CCD image sensors*MPEG-2 encoding*PCL card
TRANSMISSION & DISPLAYCAMERA 1 3D PROCESSOR DIGITAL HD ENCODERCAMERA 2 HOME 3D HD TV
TECHNOLOGIES USED*ANAGLYPHIC 3D*IT PROVIDES A 3D EFFECT WHEN VIEWED WITH TWOCOLOUR GLASSES (USUALLY RED AND CYAN).*IMAGES ARE MADE UP OF TWO COLOUR LAYERS, BUTTHEY ARE OFFSET WITH RESPECT T O EACH OTHER TOPRODUCE A DEPTH EFFECT.
POLARIZATION 3D*Two images intended for each eye are displayed from twoseparate projectors.*Each image is projected with a polarization mutuallyorthogonal to the other polarization.*Polarized 3d glasses are then used with polarized filters toensure that each eye receives only the intended image.*It works well, and the required glasses are cheap and light.
ALTERNATE FRAME SEQUENCING*The movie is filmed with two cameras. Then the images areplaced into a single strip of film in alternating order.*The film is then run at 48 frames per second.*Each eye glasses contains a liquid crystal layer.
AUTO STEREOSCOPIC DISPLAYS*Holographic displays: The holographic image is true threedimensional. It can be viewed in different angles without glasses.*Volumetric displays: It creates a 3d imagery via theemission, scattering or relaying of illumination from well definedregions in (x,y,z) space.*Parallax displays: It emits spatially varying directional light.The panorama gram, invented in 1824, is an instrument used toobtain the illusion of depth on a flat source.
*Lenticular display: The lenticular sheet is a line of array ofnarrow cylindrical lenses called lenticules.The purpose of the lenses is to focus more of the light into ahorizontal beam and allow less of the light to escape above andbelow the plane of the viewer.
3D VIEWERS active viewer passive viewershutter systems polarization systems
SHUTTER SYSTEM It generally uses liquid crystal shutter glassesA Shuttersystem works by openly presenting the image intended for theleft eye while blocking the right eyes view, then presentingthe right-eye image while blocking the left eye, and repeatingthis so rapidly that the interruptions do not interfere with theperceived fusion of the two images into a single 3D image
POLARIZATION SYSTEMSTo present stereoscopic pictures, two images are projectedsuperimposed onto the same screen through polarizing filtersor presented on a display with polarized filters. For projection,a silver screen is used so that polarization is preserved. Theviewer wears low-cost eyeglasses which also contain a pair ofopposite polarizing filters.
Colour anaglyph systemsAnaglyph 3D is the name given to the stereoscopic 3D effectachieved by means of encoding each eyes image using filtersof different (usually chromatically opposite) colours, typicallyred and cyan. Anaglyph 3D images contain two differentlyfiltered coloured images, one for each eye.
Chromadepth systemThe ChromaDepth procedure of American Paper Optics isbased on the fact that with a prism, colours are separated byvarying degrees. The ChromaDepth eyeglasses contain specialview foils, which consist of microscopically small prisms.
Pulfrich methodThe Pulfrich effect is based on the phenomenon of the humaneye processing images more slowly when there is less light,as when looking through a dark lens. Because the Pulfricheffect depends on motion in a particular direction to instigatethe illusion of depth, it is not useful as a general stereoscopictechnique.
3D TV MANUFACTURERSSome of the major 3d TV manufacturers are:*Toshiba*LG*Philips*Sony*Samsung
SONY*launched in 2010LG*launched in 2010PHILIPS*launched in 2011
SAMSUNG*launched in 2011TOSHIBA*launched in 2010
APPLICATION OF 3D TV TECHNOLOGY*In the field of medicine, education.*Entertainment and gaming.*Military and communication field.*Richer, lifelike and entertaining experience than 2d TV forhome users.*In engineering field for simulation and visualization.
DISADVANTAGES*Greater 3d experience requires glasses to be worn whileviewing.*No defined industry standard for 3d hardware, software andTV components.*High production and transportation costs of 3d videoinformation.*Health problems may occur.
CONCLUSION*Thus we have seen various technologies used for 3d imagingand viewing.*We also explained technology of 3d TV, discussed variousaspects and features of 3d TV.*Another area of future research is precise colour reproductionof natural scene on multi view displays.*In future we will be able to touch and smell the objects beingprojected from a screen to the viewers.