The ophthalmology professor, Sparrow, from Columbia University Medical Center, said that most people, old or young, should not wear blue glasses. Doctor Sparrow is investigating that if it will cause macular degeneration when eyes contact the blue light in the sunlight. This degeneration is the main cause that leads the blindness of the elderly. She believes that as age increases, there will be more and more photosensitive compounds in some retinal cells. And the wavelength of blue light in the spectrum can activate these compounds to the max, which accelerate the release of harmful free radicals. It threatens eyes’ health as oxidation process which hurts the retinal cells.
Blue sunglasses will indeed do damage to the health of eyes. On one hand, its wavelength is very short, so human eyes will have the smallest view in blue light, which will cause viewers unable to see objects clearly. On the other hand, blue is the color closest to UV, which is also detrimental to the optic nerve and easily causing injury to the eye. Clinically, a number of optic nerve diseases have been confirmed in relation to the blue ray.
Besides blue lenses, the popular colorful contact lenses with blue strips on the market also do harm to eyes. So we should be care when choosing glasses. So, which color is safe when we are buying eyewear? Professor Sparrow believed that sunglasses yellow or brown is the best to choose. As the yellow light has an intermediate wavelength, it leads the human eyes to be the most sensitive to yellow, so that nature’s scenery looks clearer. Furthermore, yellow sunglasses can filter blue light and decrease blue light quantity to eyes, which can protect eyes efficiently. Besides yellow or brown glasses, black glasses is a good choice too, because it can decrease the touch with other color sunlight.
Finally, doctor reminds consumers that the current sunglass market is complicated, many eyeglasses are disqualified. When choosing a reading glasses, select the one with the function of ultraviolet resistance whose index is usually between 96% and 98%; Don’t select the sunglasses of too dark colors because the light transmission of such lens will decline dramatically and prompts the pupils to expand in the dark, which harms the eyes.