Dr. Sparrow, the ophthalmic professor at Columbia University Subsidiary Medical Center in America said: " most people including the old and the young should not wear blue eyeglasses." Dr. Sparrow is searching that whether the eyes' contact with the blue light of solar rays will cause the age-related macular degeneration. This kind of degeneration eye diseases is the main reason of the blindness of the old. She believes that as age increased, the photosensitive compounds in some retinal cells will be more and more. While the wavelength of Blu-ray in the spectrum can activate these compounds to an extreme and promote the release of harmful free radicals. It threatens eyes' health as oxidation process which hurts the retinal cells.

Blue sunglasses are really harmful to eyes' health. On one hand, blue light has short wavelength, so in the blue light, human eyes has the smallest ken and can not see things 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.

In addition to the blue sunglasses, the popular colorful lenses with blue stripes in the current market are also hazardous to eye health and options should be cautious. Then, with which color are the cheap glasses safe? Professor Sparrow says that sunglasses of yellow or brown are the best choice. 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. Moreover, yellow sunglass can also filter blue light, and then decrease the number of blue light. So it can protect eyes' health effectively. Apart from yellow and brown lens, black lens is also a good choice because it lessens the contact with lights of all colors.

At last, the doctor reminds consumers that there is a mingling of good and evil on sunglasses market and the quality of many glasses is poor. We should choose UV capabilities when we choose glasses, and the anti-UV index is usually between 96%-98%. You'd better not choose deep color, for the transmittance of this kind of glasses will decrease badly. It results in mydriasis and makes your eyes damaged.