The description of what they do on ThinkGeek seems a lot more helpful than the actual gunnar website. And it makes at least some sense to me that just having tinted lenses would help reduce eyestrain if the blue spectrum is actually what is causing strain.
The human eye is a magnificent device. Refined over millions of years of evolution, it's a highly specialized and effective organ that helps us hunt prey, spot berries, and spot and dodge swinging clubs. As humanity continued to evolve, however, we relied more on the tools we manufactured rather than the ones with which we were born.
Now we have more so-called "knowledge-workers" than ever, spending all day tied to desks, and staring at computer screens. We've traded sore backs and calluses for headaches and dry and tired eyes. You rub your eyes, and drip drops into them but that doesn't really help, does it?
You see, high-efficiency fluorescent lighting and computer monitors in our offices are highly shifted towards the blue-end of the spectrum. The problem is, blue light focuses differently on the retina than the rest of the spectrum. Ever look at a blue LED and noticed a halo around the light? Staring at it gives you a headache, doesn't it? Guess why! Your eyes are straining to try and bring that fuzzy spot into focus, and it just can't!
What you need is a way to filter out some of those blues that give your eyes so much trouble. Our new Gunnar Computer Glasses shift that light to the warmer end of the spectrum, giving your tired eyes a chance to recover. Not only do they filter blue light, they also reduce glare, helping with eye strain even more.