Do the blue light filters on glasses work?
We have many patients ask us about this relatively new technology for their glasses. Does it really work? Is it just a marketing ploy? Do my kids need this on their glasses? Let’s dig into some of these questions.
Blue light itself isn’t inherently bad. In fact, it is all around us. We really get more exposure from the sun than we do from our electronics. On the light spectrum, only a small portion of light is visible to us. Warm colors like red and orange have lower wavelengths and cooler colors like blue have higher wavelengths - hence higher energy. Our ancestors were exposed to blue light during the day, which is great because it promotes wakefulness, attention, reaction times, and a stable mood. But in our modern society, we are constantly immersed in artificial light, mostly lower wavelengths (i.e. blue), from all of our tablets, phones, laptops, televisions, and computer monitors. Too much blue light suppresses the secretion of melatonin, which is a hormone that makes us sleepy and therefore, too little melatonin can interrupt our sleep cycles.
Researchers with the University of Toledo found that blue light sets off a toxicity in the eye that kills off the photoreceptor cells in the retina. These photoreceptors are the cells that are responsible for vision and they do not repair or regenerate themselves. The cornea, lens, and other structures in the eye cannot block or reflect blue light before it reaches the retina. It seems that no poisonous molecules are produced by red, green, or yellow light. However, the toxicity produced by blue light or high-energy, short wavelength light is non-discriminating and it can kill any type of cell.
The ads are everywhere―on Facebook, in local magazines, even in pop-up ads―warning you against the damage your electronics are causing in your eyes. But there really is no conclusive evidence yet that this kind of light from our computers and tablets is damaging the eyes. Recent research has found a link between blue light and age-related macular degeneration and other retinal problems. However, this was done in animal studies. It is more difficult to track the long-term effect of blue light in humans because there are so many variables.
That said, even though the studies and research are still being conducted, I recommend the blue light blocking filters on glasses for any of my patients that spend any time at all on digital devices, particularly if they have any complaints of not sleeping well.
In addition to blue light anti-reflective coated lenses, there are settings on your devices that will reduce the emission of blue light. This setting will take out all of the blue light from showing on your screen and will make the light softer, yellower, and easier on your eyes. Long hours staring at digital devices contributes to significant eye strain and computer vision syndrome. Digital devices are not going away, and eye strain comes from the duration of their use, not something coming out of the screens. There are certain things that can help make you more comfortable:
Adjust the room lighting to decrease contrast on your screen.
If you wear contact lenses, consider wearing your glasses on occasion to allow your cornea greater access to oxygen.
Take frequent breaks every 20 minutes while using your devices by shifting your focus to 20 feet away for at least 20 seconds (the “20-20-20 rule”)
Consider using artificial tears. Decreased blinking while staring at a computer screen contributes to dry.
Add a filter to your devices. Blue light filters are available to fit over cellphones, tablets, and computer screens to block the emitted blue light.
Switch to prescription computer glasses with single vision lenses. These glasses can ease the eye strain of using progressive lenses thanks to the added benefit of a much larger field of view to see your monitor, versus a small area of an overall lens with a progressive.
A square face has defined angles and balanced lines along the forehead, chin and cheeks. An oval or round frame will complement these strong features and soften them.
The width and height of a round face will be roughly similar. In order to elongate and play down the fullness of the cheeks, select a frame with strong angles and straight lines.
An oval face is defined by higher cheekbones and a chin that is narrower than the forehead. Frames that sweep upward complement the cheekbones and slim down the jawline.
A heart-shaped face has a long, pointed jawline, with the chin being the smallest feature. Over-sized frames complement this shape and balance out the forehead and narrow chin.