3D Projectors For The Home Theater

I love going to the movies. Always have and always will. Now that we have 3D movies I'm like a little kid in a candy store. Any excuse is good enough for me to experience the fantastic 3D effects they are coming out with these days. Fortunately I have four little girls who also like an outing to the movie theater and enjoy a good 3D film as much as the next person and not just movies made for girls either.

All 3D technology uses a system of presenting two slightly different pictures to the viewer but making sure your eyes see only one image each. In other words the right eye will see one picture and the left eye will see another slightly different picture. As each eye perceives the world from a slightly different perspective due to them being about 2 inches apart this effectively mimics the way we see the real world and creates a more realistic 3D image on a 2D screen. All 3D images are created this way but there are two or three different methods used to achieve the effect.

Firstly, let's get the anaglyph method out of the way. For those who might not know anaglyph is the technical term for using glasses with red and blue tinted lens. The two separate images for the eye are created with either a red or a blue tint. The glasses filter out the correspondingly colored image so each eye sees a separate image. This technique is a novelty at best and is not really suitable for enjoying 3D movies in high definition full color.

Active shutter glasses use a method that is technically known as alternate-frame sequencing. Each eye has it's view blocked by the lens going dark when the image that it is not supposed to be seeing is on the screen. For this method you effectively need to double the frame rate of playback as each eye is only seeing half of the animation. Modern TVs and projectors are more than capable of this however.

There are pros and cons to using active shutter glasses. A disadvantage is that you either need to be tethered to a box with a cable or you need to buy batteries for glasses that operate remotely. When you have a large family that can add up to quite a mess of cables or quite a lot of batteries. The major advantage is that the technology has been around for a while now and projectors using this method are relatively cheap. Great news if you have a small or no family and only need one or two pairs of glasses.

A new system of displaying 3D images is slowly gaining a foothold in the market place. This system uses polarized light for projecting images onto a
screen and it is now possible to display both images on the screen simultaneously. Special polarized lenses in the glasses are polarized to only let in the correct image while blocking the other.

There are some major advantages to this method but the one limiting disadvantage is that it is prohibitevely expensive to the average home user. Another disadvantage is that you will need to buy a silver screen to get the best viewing experience. Silver screens reflect the light in such a manner as to ensure there is minimal depolarization for a crisper picture. This means using the trusty old white bedsheet is out as they throw light back in all sorts of directions.

The polarized technique has some major advantages that will enable it to become the dominant method when prices finally do come down. The glasses are lighter, cheaper and don't require batteries. You can also have a more widely dispersed audience as the 3D effect is viewable from more angles. Shutter glasses also have a tendency to darken the image by about 20%. Polarized glasses can reduce this to about 10%.