How to avoid 3D TV Eye Strain and Eye Fatigue
Is it a Problem?What are the Causes?
By Jack Burden, Senior Reviewer
We receive lots of questions about this issue. Some people just steer clear of 3D TV altogether due to the reputation for eye fatigue. We've all heard of people saying they get headaches when viewing 3D TV for long.
Truth be told, 3D TV viewing is probably not for everyone (shh, dont let the TV manufacturers hear that.) There are convergence issues with any 3D technology – passive polarization technology, active shutter glasses which sequentially open and close the right and left eye – even the most advanced new 3D technologies. For the this article though, let's stick with active shutter and passive 3D technologies.
What causes the eye strain or fatigue? Signal processing by your brain. Your eyes are trying to convince your brain that they are seeing 3D images when in fact they are not. The technical explanation for this is that your eyes are having to view a film sequence through lenses that are flashing at 60 flashes per second (each on a 120Hz TV). This flashing occurs to allow one eye and then the other to see a separated picture – thus creating the 3 dimensional effect.
Recently, a study was published by the Journal of Vision and conducted by UC Berkeley (partially funded by Samsung). The study was primarily established to find out what, if any, effect distance plays in viewing 3D video content. The study concluded that with improper vergence accommodation, eye fatigue or strain occurred more severely. To be more specific, the study found that when the viewer was too far from the 3D TV, or too close to the TV, they experienced more eye fatigue – this test does not appear to have tested the the difference between active and passive 3D, if there is a difference. The main point is that the brain has to process both the 3D signal processing and adjust to the distance of the content. Therefore, viewing 3D from the correct distance is one of the ways to cut down on 3D eye strain and avoid those headaches. Following is a 3D viewing distance chart that we recommend depending upon your screen size:
TV Size (in diagonal inches)
Recommended 3D TV Programming Viewing Distance
|52"||9 to 10 feet|
|55"||10 to 11 feet|
|60"||12 to 13 feet|
|63"||13 to 14 feet|
Now for our take on the eye fatigue issue. For one, your oculars may be slightly strained or fatigued when viewing 3D content, but it's nothing to be concerned about. If you read for 6 hours straight your eyeballs will also feel tired. They recover fast. They are capable of handling the experience and recovering very quickly - as most people are finding out. I experienced more eye fatigue in 2010 when reviewing TVs than I do now – by far. Why? The active shutter glasses and transmitters on the TVs are syncing better. Passive 3D is even a little less intrusive. In sum, the technology is getting better.
3D TV content is not so much about the newest greatest and latest experiment with TVs. In this writers opinion, it's about involving the viewer more in the experience of what's happening on screen. I believe some content is succeeding in this quest. Does it engross you more in the movie? Yes, most times it does.
Active vs. Passive 3D
From our experiences with a dozen 3D TVs that we've reviewed this year, active shutter 3D TV picture quality is much smoother with little if any of the flashing and blurring that we saw last year. Still, passive 3D while not containing quite as much depth seems to have even less eye fatigue or strain than active shutter technology. That's our take. Many would argue, but we do see a lot of these TVs. So if eye fatigue is a major consideration for you, you might think about passive over active 3D, in conjunction with the above viewing distance chart in cutting down 3D viewing side effects.