The document discusses various types of 3D glasses used for viewing stereoscopic images, including active, passive, anaglyph, infitec, and polarized glasses. Each type employs different technologies to deliver specific images to each eye, enhancing the perception of depth. The history and applications of these technologies are also highlighted, including their use in theaters, medical imaging, and early 3D films.

1. DESIGN ENGINEERING

2. Introduction
• Any 3D (3-Dimensional) content has two sets of frames, one for each eye.
• In order to see the 3D effect, we need to make sure that each eye sees only the video or image that is intended
for it, which is why we use 3D glasses.
• All 3D glasses are equipped with special lenses that make sure this will happen, they filter only the left frame to
the left eye and the right frame to the right eye.
• The difference between each type of 3D glasses is in the way they do that.
There are two categories of 3D glass technology, active and passive.
• Active glasses have electronics which interact with a display.
• Passive glasses filter constant streams of binocular input to the appropriate eye.

3. 3D Glasses
Infitec 3D
Glasses
Active Shutter
3D Glasses
Passive GlassesActive Glasses
Anaglyph 3D
Glasses
Polarized 3D
Glasses
Circularly
Polarized
Linearly
Polarized

4. Active Shutter 3D Glasses
• An active shutter 3D system (a.k.a. alternate frame sequencing, alternate image, AI, alternating field, field
sequential or eclipse method) is a technique of displaying stereoscopic 3D images.
• It works by only presenting the image intended for the left eye while blocking the right eye's view, then
presenting the right-eye image while blocking the left eye, and repeating this so rapidly that the interruptions do
not interfere with the perceived fusion of the two images into a single 3D image.
• The glasses are controlled by a timing signal that allows the glasses to alternately block one eye, and then the
other, in synchronization with the refresh rate of the screen.

5. Applications
• Active shutter 3D systems are used to present 3D films in some theaters, and they can be used to present 3D
images on CRT, plasma, LCD, projectors and other types of video displays.
History
• This 3D glasses made its public debut remarkably early. In 1922, the Tele view 3-D system was installed in a single
theater in New York City.

6. Anaglyph 3D Glasses
• Anaglyph 3D is the name given to the stereoscopic 3D effect achieved by means of encoding each eye's image
using filters of different (usually chromatically opposite) colors, typically red and cyan.
• Anaglyph 3D images contain two differently filtered colored images, one for each eye. When viewed through the
"color-coded anaglyph glasses", each of the two images reaches the eye it's intended for, revealing an
integrated stereoscopic image. The visual cortex of the brain fuses this into the perception of a three-
dimensional scene or composition.
Applications
• Examples from NASA include Mars Rover imaging, and the solar investigation, called STEREO, which uses two
orbital vehicles to obtain the 3D images of the sun. Other applications include geological illustrations by
the United States Geological Survey, and various online museum objects.

7. • A recent application is for stereo imaging of the heart using 3D ultra-sound with plastic red/cyan glasses.
• On April 1, 2010, Google launched a feature in Google Street View that shows anaglyphs rather than regular
images, allowing users to see the streets in 3D.
• These techniques have been used to produce 3-dimensional comic books, mostly during the early 1950s,
using carefully constructed line drawings printed in colors appropriate to the filter glasses provided.
History
• The oldest known description of anaglyph images was written in August 1853 by W. Rollmann in Stargard about
his "Farbenstereoscope" (color stereoscope). He had the best results viewing a yellow/blue drawing with
red/blue glasses. Rollmann found that with a red/blue drawing the red lines were not as distinct as yellow lines
through the blue glass.
• In 1858, Joseph D'Almeida began projecting three-dimensional magic lantern slide shows using red and green
filters with the audience wearing red and green goggles.
• Louis Ducos du Hauron produced the first printed anaglyphs in 1891. This process consisted of printing the two
negatives which form a stereoscopic photograph on to the same paper, one in blue (or green), one in red.

8. • William Friese-Green created the first three-dimensional anaglyphic motion pictures in 1889, which had public
exhibition in 1893. 3-D films enjoyed something of a boom in the 1920s. The term "3-D" was coined in the 1950s.
Infitec 3D Glasses
• Infitec 3D glasses are actually an upgrade of the anaglyph 3D glasses and are sometimes called “Super-
Anaglyph” glasses.
• Each image for each eye is encoded with slightly different red, green and blue colors. The differences are so slight
that our brain hardly notices them, but they are strong enough to be filtered by the glasses’ lenses, and each
slightly different image is filtered to the intended eye.
• The 3D effect of Infitec 3D glasses is very good, but the system is somewhat complicated to set up at home. The
Infitec 3D system and glasses are being used mostly in cinemas.

9. Polarized 3D Glasses
• A polarized 3D system uses polarization glasses to create the illusion of three-dimensional images by restricting
the light that reaches each eye.
• To present stereoscopic images and films, two images are projected superimposed onto the same screen or
display through different polarizing filters.
• As each filter passes only that light which is similarly polarized and blocks the light polarized in the opposite
direction, each eye sees a different image. This is used to produce a three-dimensional effect by projecting the
same scene into both eyes.
Types of polarized 3D glasses:-
1) Linearly Polarized Glasses
• To present a stereoscopic motion picture, two images are projected superimposed onto the same screen
through orthogonal polarizing filters (Usually at 45 and 135 degrees).

10. • The viewer wears linearly polarized eyeglasses which also contain a pair of orthogonal polarizing filters oriented
the same as the projector. As each filter only passes light which is similarly polarized and blocks the orthogonally
polarized light, each eye only sees one of the projected images, and the 3D effect is achieved.
• Linearly polarized glasses require the viewer to keep his or her head level, as tilting of the viewing filters will
cause the images of the left and right channels to bleed over to the opposite channel. This can make prolonged
viewing uncomfortable as head movement is limited to maintain the 3D effect.
• A linear polarizer converts an unpolarized beam into one with a single linear polarization. The vertical
components of all waves are transmitted, while the horizontal components are absorbed and reflected.

11. 2) Circularly Polarized Glasses
• To present a stereoscopic motion picture, two images are projected superimposed onto the same screen
through circular polarizing filters of opposite handedness.
• The viewer wears eyeglasses which contain a pair of analyzing filters (circular polarizers mounted in reverse) of
opposite handedness.
• Light that is left-circularly polarized is blocked by the right-handed analyzer, while right-circularly polarized light
is extinguished by the left-handed analyzer.

12. • The result is similar to that of stereoscopic viewing using linearly polarized glasses, except the viewer can tilt his
or her head and still maintain left/right separation.
• By rotating either the QWP (Quarter Wave Plate) or the LPF (Linearly Polarized Filter) by 90 degrees about an
axis perpendicular to its surface (i.e. parallel to the direction of propagation of the light wave), one may build an
analyzing filter which blocks left-handed, rather than right-handed circularly polarized light.
• Interestingly, rotating both the QWP and the LPF by the same angle does not change the behaviour of the
analyzing filter.
Applications
• Polarizing techniques are easier to apply with cathode ray tube (CRT) technology than with Liquid crystal
display (LCD). Ordinary LCD screens already contain polarizers for control of pixel presentation — this can
interfere with these techniques.
• In optometry and ophthalmology, polarized glasses are used for various tests of binocular depth
perception (i.e. stereopsis).

13. History
• Polarized 3-D projection was demonstrated experimentally in the 1890s. The projectors used Nicol Prisms for
polarization.
• Packs of thin glass sheets, angled so as to reflect away light of the unwanted polarity, served as the viewing
filters. Polarized 3-D glasses only became practical after the invention of Polaroid plastic sheet polarizers
by Edwin Land, who was privately demonstrating their use for projecting and viewing 3-D images in 1934.
• They were first used to show a 3-D movie to the general public at "Polaroid on Parade", a New York Museum of
Science and Industry exhibit that opened in December 1936.
• Linear polarization was standard into the 1980s and beyond.
• In the 2000s, computer animation, digital projection, and the use of sophisticated IMAX 70 mm film projectors,
have created an opportunity for a new wave of polarized 3D films.
• In the 2000s, RealD Cinema and MasterImage 3D were introduced, both using circular polarization.
• At IBC 2011 in Amsterdam RAI several companies, including Sony, Panasonic, JVC & others highlighted their
upcoming 3D stereoscopic product portfolios for both the professional and consumer markets to use the same
polarization technique as RealD 3D Cinema uses for stereoscopy.

14. Advantages
• Generally inexpensive.
• Do not require power.
• Do not require a transmitter to synchronize them with the display.
• Do not suffer from flicker.
• Lightweight & Comfortable.
Disadvantages
• The images for polarized glasses have to share the screen simultaneously in which full, native resolution is
downgraded, compromising picture quality of both sides of the image delivered to each eye simultaneously. A
full 1080p picture results from image fusion. This disadvantage does not occur on projections where each pixel
can contain information for both eyes.
• Associated with the headaches many people attribute to 3D viewing.
• Narrow vertical viewing angles compared to Active shutter 3D.

15. Thank You