XpanD | Absolute Sound

There is a lot of confusion with respect to 3D regarding the wide range of 3D glasses and the products and brands that they will work with. Questions abound: Will the ‘tired and true’ red/blue 3D glasses work with everything, or do you need different color glasses for different sources? What about the polarized 3D glasses like they use at Disney? Will you be able to take your Samsung 3D glasses from the family room to watch your Panasonic 3D TV in the bedroom? Will your active-shutter glasses work at the local cinema? Confused? Let’s see if we can give you a better understanding of 3D by explaining how it works and describing the different types of glasses needed for the different systems.

The Power of Love was the first ever 3D movie. It came out in 1922 and was the only film released in the two-camera, two-projector stereoscopic 3D process. While many thought that Bwana Devil, released in the 3D crazed 1950’s was the first 3D movie, it actually debuted 30 years too late.

 

How 3D works:

Humans come equipped with two eyes spaced about 2 inches apart. This two-eye view creates binocular vision which in turn gives us a 3-Dimensional image from everything we see. Don’t believe it? Try closing one eye and have someone throw you a ball and try to catch it. With one eye closed you lose the ability to properly discern depth and width. It’s like the difference between looking through a telescope, or mono vision, as opposed to a pair of binoculars which gives you stereo vision. For those of us that are old enough to remember, a View-Master viewer was an early stereoscopic viewer that provided a separate image to each eye. The resulting image was a lifelike 3-dimensional picture.

When you go to a movie theater to see a 3D epic like Avatar, you wear 3D glasses so they can feed two separate images to your eyes. Two projectors are synchronized to project two images or views onto the screen, and the glasses cause one image to enter one eye and the second to enter into the other eye. The result is a spectacular lifelike 3 Dimensional picture, or what we call 3D.

 

There are two basic systems for viewing 3D:

 

Red/Green or Red/Blue 3D Glasses
Although the red/green or red/blue system is now mainly used for television 3D effects, it was used in many older 3D movies. In this system, two images are displayed on the screen, one in red and the other in blue (or green). The red and blue lenses filter the two images allowing only one image to enter each eye, and then your brain does the rest. You cannot really have a color movie when you are using color to provide the separation, so the image quality is not nearly as good as with the polarized system.

 

Polarization
At Disney World, Universal Studios and other 3D venues, the preferred method uses polarized lenses because they allow color viewing. Two synchronized projectors project two respective views onto the screen, each with a different polarization. The polarized glasses allow only one of the images into each eye because each lens has a different polarization.

 

So which type of 3D glasses will you need?

3D Fireworks glasses – Specially treated holographic lenses break light into the spectrum through a process called holographic diffraction grating. They make an exciting addition to fireworks displays, laser light shows, city and holiday lights. While these add a cascade of shimmering light to outdoor displays, they should not be used for viewing 3D video displays.

 

Anaglyph 3D glasses – These are the ones you have probably owned at least one time in your life. The most popular ones are made out of paper with a cellophane lens and are extremely low in cost (and disposable). There are also higher-quality plastic framed versions of this popular format which fit over most regular frames with corrective lenses. They come in various lens color combinations, but Red / Blue is the most popular. They also come in Red / Cyan or Red / Blue-Green or Magenta / Green for optimum viewing of different sources.

 

Anaglyph 3D Clip On Lenses – Another way to get the 3D experience without having to wear an additional pair of glasses is to use the handy flip-up style that fits over most corrective lenses. These clip right on to your existing glasses so wearing them is very natural.

 

So which color combination should I use?

For the new Monsters vs. Aliens, Coraline, My Bloody Valentine in 3D and Journey to the Center of the Earth 3D, choose Magenta / Green 3D glasses… remember the Magenta lens goes over the right eye!

For viewing 3D Blu-ray discs like Hanna Montana 3D, Polar Express, Shrek 3D, Barbie 3D and theAdventures of Shark Boy and Lava Girl, choose Red / Blue 3D Glasses. Be sure you have a 3D-ready Blu-ray player connected directly up to your display device with a high-speed HDMI cable (must meet the 10.2 Gbps data rate at 340MHz). We recommend a direct hookup because not all A/V receivers can pass a proper 3D signal, and we won’t have a full understanding of what will and won’t work until more product hits the market.

Pulfrich 3D Glasses- (named for Carl Pulfrich , the creator, who never actually lived to see it) should be used For viewing TV in 3D. The 3D effect is based on the phenomenon of Dark and Clear lenses. The image through the dark lens reaches the brain slightly later than the image through the clear lens, thus creating the illusion of 3D. It works with objects or scenes moving horizontally across the field of view but not vertically. This is one of the only viable ways to experience broadcast TV in 3D. Because the Pulfrich effect depends on motion in a particular direction to instigate the illusion of depth, it is not useful as a general stereoscopic technique. The Pulfrich method of 3D is used for TV, video, and computer screens. These 3D TV viewers are great for viewing live sporting events in HD.

 

Linear or Circular Polarized 3D Glasses - – These are the plastic polarized glasses that you see at the theme parks (Disney, Universal, IMAX) and are used primarily in movie theatres. They WILL NOT WORK for home movies, home theatre or TV. In a movie theater, the reason why you wear 3D glasses is to feed and separate two different images into your eyes. Two projectors are synchronized and project two respective views. The screen actually displays the two images, and the glasses cause one of the images to enter one eye and the other image to enter the other eye. They come in two angles of orientation: most commonly used are the linear polarized glasses, while the circular polarized are used for StereoGraphics Z-screen and Real D theaters.

 

LC or Active Shutter glassesare glasses used in conjunction with an HD display screen to create the illusion of a three dimensional image, an example of stereoscopy. Glass containing liquid crystal and a polarizing filter has the property that it becomes dark when voltage is applied, but otherwise is transparent (just like the chromatic glass doors we have in the conference room in our showroom). The glasses are controlled by an IR or RF, DLP-link or Bluetooth transmitter that sends a timing signal. The glasses alternately darken over one eye, and then the other, in synchronization with the refresh rate of the screen, while the display alternately displays different perspectives for each eye, using a technique called Alternate-frame Sequencing (which effectively cuts the refresh rate in half) . They are called LC shutter glasses (since they do not feature a liquid crystal display) or Active shutter glasses. 3D glasses maker XpanD says its glasses will work with 90 percent of 3D TVs that come to market, and the company expects to roll out fashion, designer, and even prescription 3D glasses. Accessory glasses won’t be cheap, selling for $50-$250 depending on lens type, construction, materials and style–and depending on the designer name on the frame.

 

Health concerns – Some people who watch 3D experience motion sickness and nausea, headaches, and eye strain. It usually goes away, but if it doesn’t then you shouldn’t watch 3D . Additionally , some people have stereo blindness, resulting in an inability to perceive stereoscopic depth when combining two images. These people cannot get the benefit from a 3D experience either .