We’re geeks, admittedly. We’re quick to embrace and adopt new technologies. Being tech junkies, we’ve certainly gone to many 3-D films in theaters, and we’ve done our research on 3-D home entertainment. Most people are still pretty confused about how it all works, so let me try to clear things up. First things first, in order for our brains to translate images as having depth, we must view the world through 2 eyes. Each eye is spaced apart, and views a slightly different image. Our brains put the two images together to form one 3D image with depth.

3D in Theaters

You’ve probably heard that some movies (such as Avatar) were filmed using special 3D cameras, while others, (Clash of the Titans) were filmed in 2D and later converted to 3D in post-production. 3D cameras work by filming the scene through two lenses next to one another. One lens records what your left eye would see, the other records the right eye. in the case of Clash of the Titans and Alice in Wonderland, the 2D film had to be digitally separated into two images. Artists create depth information to the scene whereby computers create the left & right images. It’s the “dirty” way to get 3D and in my opinion is like painting an old black & white movie into color. It usually does not add anything to the movie, but rather feeds a consumer demand (or is that, manufactured demand?)

Whether the film was shot in native 3D, or converted to 3D by a team of artists and tech wizards, how is it shown in 3D in theaters? The short answer is, through polarization. Still-image photographers are already familiar with polarization. They use polarized filters on their lenses to “block” certain light waves. For instance when photographing outdoors, you can filter sunlight with a polarized filter to reveal more color depth in the sky and reveal clouds better. Adjusting the level of polarization simply requires rotating the filter. In theaters, there are polarized filters on the projector lens(es). Some theaters use one projector to reveal the 2 images, separated by a polarizing filter that alternates polarization many times a second. Other theaters use two separate projectors, one with a clockwise polarization filter, and the other with a counter-clockwise filter. The glasses you receive have polarized lenses as well. The left-eye lens is polarized such that it blocks the light emitted by the right-eye projector.

Why can’t I see 3D on my computer screen with my 3D Theater Glasses?

As mentioned above, these glasses only work if you’re viewing light which has passed through a matching polarization process. If you want proof your glasses are polarized, try looking at your computer monitor through the glasses. Looks pretty normal right? Now try tilting your head 90 degrees to the left or right. Pretty trippy right? Now try taking the glasses off, and holding them up to your screen. Hold the outside of the glasses towards you, and the inside towards the monitor and try rotating them again. You’ll notice that at a particular angle of rotation (varies by monitor), the monitor’s light is completely blocked out. You can still see through the lenses (try waving your hand behind the lens), but only the monitor’s light is “blocked.” The reason for this, is your monitor has its own UV polarization which is not circular, but linear.

Okay so what about 3D Televisions?

You might remember those cheap paper red and cyan Stereoscopic 3D glasses. Anaglyphic 3D is the process whereby color filtering is used. Your left eye is covered with a red filter, and your right eye is covered with a cyan filter (or amber/violet or red/green.) Where the image displays only red, your left eye is “blocked.” In fact, you can view anaglyphic 3D images on your monitor or television with cheap glasses now. The problem with this method is you cannot achieve great color depth if you are eliminating observed colors, not to mention you lose brightness while looking through a color filter. This method is mostly for black & white images and isn’t nearly as advanced as the polarizing method. There is currently no way to use a television or monitor to create two separately polarized images. Therefore, to “block” the left and right eye images, they have devised a clever method called Active Shutter whereby you wear glasses which have batteries and actively “shut” one eye’s shutter while “opening” the other eye’s shutter. 3D televisions rapidly switch between the left-eye image to the right-eye image 120 or 240 times per second. This means each eye is viewing the image 60 or 120 times per second, and allowing the illusion of depth. The drawbacks are that without specially synched glasses on, you’ll be staring at a very fuzzy image. Furthermore, there is not currently a standardized synching method so your Panasonic glasses only work with your Panasonic 3D television. The glasses are expensive too, costing over $200, not to mention you would need a pair for each person viewing the 3D television. 3D televisions cost about $4,000 for a 55″ right now, but that’s a lot cheaper than the extremely expensive 3D projectors found in movie theaters. Here is a video demonstration of some active shutter lenses in action.

Is there demand for this stuff?

Independent marketing agencies predict the market for 3D technology will grow rapidly; about $1B in late 2009 to over $50B in 2015. Hollywood has been spending millions to convert 2D films to 3D to sell more expensive tickets and promote new expensive equipment to theater owners. Sony Playstation has heard the cry for 3D and are planning the release of Gran Turismo 5 intended for November 2nd, 2010 to include the option to play in stereoscopic 3D. In many ways it makes sense for console gamers to adopt 3D before everybody else. Gamers love new technology, they have the money to invest in it, and displaying games in 3D has the potential to add a lot of gaming value. In addition, Sony’s Playstation 3 and Microsoft’s Xbox 360 are already designed to easily download firmware updates. Playstation 3 gamers with a 3D television can download a software upgrade this summer to start enjoying a few titles in 3D. As for 3D broadcast television, well it will take some time for networks to adopt the technology and start displaying shows in 3D. For networks which only recently adopted HD, it may be too much investment to fathom purchasing all new expensive equipment and training technicians. My personal position is that I’m waiting until I see where the technology is going to go. I’m not yet convinced that people want to wear expensive electronic glasses to view their favorite shows. I’ve heard rumors that manufacturers are engineering televisions with polarizing filters built into the displays. If that technology pans out, it may allow us to enjoy the illusion of 3D without wearing expensive 3D glasses on our faces.