Blue light is a type of electromagnetic radiation with a very short wavelength that produces a high amount of energy. While it's true that light can damage your eyes under certain circumstances, there's no scientific evidence suggesting that blue light is harmful to our eyes. But many people still think it is, which is why blue light-blocking glasses are so popular.

蓝光是一种波长非常短、能量巨大的电磁辐射。虽然在某些情况下光线确实会损伤我们的眼睛，但是目前并没有科学证据表明蓝光对我们的眼睛有害。不过许多人仍然认为蓝光确实有害，这就是防蓝光眼镜如此受欢迎的原因。

"Everyone is very concerned that (blue light) may be causing damage to the eye, and it's a valid concern, but there's no evidence it may be causing any irreversible damage," Dr. Rahul Khurana, clinical spokesman for the American Academy of Ophthalmologists, told Business Insider.

Blue light exposure is nothing new. In fact, the sun is the largest source of blue light. Moreover, blue light is also present in fluorescent and LED light.

But if blue light isn't harmful, then why are we constantly rubbing our peepers when we're looking at our screens? The answer is eyestrain: More than 60 percent of people experience problems associated with digital eyestrain. And blue light, it seems, isn't the cause. Instead, our eyes are so strained because most of us blink less when we stare at our digital devices.

So if eyestrain is the real issue, blue light-blocking glasses are probably useless. However, wearing them could potentially help you get a good night's sleep. That's because blue light, research has shown, affects your body's circadian rhythm, your natural wake and sleep cycle. According to Harvard researchers, any kind of light -- including blue light -- can tamp down your body's ability to secrete melatonin, a hormone that helps you sleep.