3D is the new "it" feature for HDTVs, from ultra-high-end displays to more affordable sets in the $1,000 price range. Since the consumer launch of 3D HDTVs, the reception has been somewhat lukewarm. Consumers aren't too keen on the idea of wearing glasses to view 3D content outside of their local multiplexes. They don't necessarily want to buy all new equipment, such as Blu-ray players and/or 3D-capable receivers, both of which drive the cost of 3D skyward. Finally, many consumers are simply underwhelmed by the selection of 3D movies available, be they on Blu-ray or via their cable or satellite providers. Panasonic, Sony, DirecTV and Comcast are certainly trying to push 3D but it's been a fairly slow roll, which is shocking given how much credence the 3D format has been given by the studios at the theatrical level. Consumer objections aside, another troubling development for 3D centers around the physical reaction that people often have when watching 3D.

Additional Resources
• Read about possible glasses-free solutions to 3D HDTV.

As a physician and eye surgeon, it's important to know how 3D works - specifically as it relates to your eyes. To start, someone who wants to experience 3D must have sharp eyesight in both eyes and have excellent coordination and alignment of those two eyes. In other words, having 20/20 vision in both eyes and having perfect eye alignment without "crossed-in" or "wandering out" eyes will enable you to have the highest level of depth perception needed to enjoy the best of 3D. Clearly, not everyone has perfect eyesight. Before the days of 3D HDTV you didn't need excellent vision to enjoy 1080p video in 2D. 3D is a much more complicated proposition for your eyes if you want to be truly immersed in the video experience.

Just as people have different levels of vision, people have different levels of 3D vision. The lowest levels of 3D vision involve depth perception due to what scientists refer to as "image size and image overlap." For example, with image size, the actual object's size relative to another object gives clues about nearness. A larger object appears closer and a small object appears farther away. Of course, that is not always the case. For example if a mouse is standing a foot away, it is still smaller than an elephant ten feet away. But if you look closely at the mouse, its outline will overlap the elephant and thus you can tell that it is in front of the elephant due to image overlap. These two kinds of depth perception can be appreciated with only one eye with average vision. In fact, this is the primary way we perceive depth when watching 2D HDTV.

Since the right eye and the left are located a few inches apart, the
images that each eye sees are slightly different. It is this difference
of perspective between the two eyes and our brain's interpretation of
the perspective from right and left eye that produces the rich 3D
visual experience. Since the TV or movie screen is almost always a flat
surface in 2D, it doesn't provide 3D images with normal broadcasting.
But if the screen projects two different images with one perspective
for the right eye and one perspective for the left, and the viewer
wears "active" glasses that selectively filter the projected images so
that the right eye only sees the right image and the left eye only sees
the left image, our brain will receive images with different
perspectives and we can experience a fairly high level of 3D.

To have a meaningful, immersive 3D experience requires that you buy
the very best equipment in terms of a 3D HDTV set and sets of 3D
glasses.

Related Articles and Content
For other topics that are related, check out our other articles, Is 2D the New 3D?, Consumer Reports Ranks 3D TVs for the First Time, and Update: Toshiba Officially Announces 3D Without Glasses.

One of the problems many people have with even the best 3D HDTVs on
the market has to do with eyestrain from the glasses. All eyeglasses,
even nonprescription sunglasses can produce eyestrain and fatigue.
People will usually adjust to a new set of glasses over time, but
that's not always the case. Also, if you are myopic, have astigmatism
or are far-sighted, you will need to wear contact lenses when using 3D
glasses.

The potential for 3D is clearly present. Content for video games
looms as the likeliest best way to get the high WOW-factor titles in
the hands of the people who are most likely to invest big dollars early
on. Study after study shows that gamers are the most willing early
adopters. Mainstream consumers are still a little weary from the
Blu-ray/HD DVD format war and wonder when autostereoscopic 3D (meaning
no glasses) is coming. While Toshiba has reportedly made some progress
with this exciting new technology, autostereoscopic 3D is likely many
years away, thus content is going to be king with 3D right now.
Remember, HD didn't exactly have a great deal of content at launch. Big
antennas were needed to get early feeds into home theater systems. Soon
after, it was D-VHS decks that played HD-video tapes. It was a clunky
transition. Today, most content providers have the majority of their
channels in HD.

Should you buy a 3D HDTV today? Even with less-than-perfect
eyesight, the answer may be yes, but not really for the 3D performance.
Today's 3D sets are the best 2D sets in terms of speed, contrast and
brightness, thus they are the best HDTV for 99 percent of your viewing.
Consider 3D an add-on to a very good HDTV and consider value from there
when picking a set. No matter how good your eyesight is - 3D is a
somewhat compelling gimmick that needs to be viewed in its proper
perspective. With that said, you can't do better than some of the best
3D sets on the market today and with today's ultra-thin, bright,
beaming HDTVs at the heart of tens of millions of people's home
theaters or home entertainment systems - you want a top performing HDTV
in your system. The chances are higher and higher that said display
will be 3D capable.