Sunglasses are a must-have sun protection tool for summer travel. Having a good pair of sunglasses can reduce the stimulation of strong light and protect consumers' eyes from ultraviolet rays. There are sunglasses of varying prices and quality on the market today. Testers can use the standard measurement device for the transmittance of eyewear products to test the light transmittance of sunglasses, traffic signal transmittance and other project indicators that affect the performance of the glasses, and judge whether the glasses are qualified based on whether the test data meets national standards.

In the absence of professional equipment, consumers can also use four tips to choose sunglasses.

1. Observe the appearance

Observe the lens for scratches, impurities, bubbles, streaks and other defects. Regular sunglasses should be marked with product name, execution standards, category, classification, quality level, manufacturer name and address, trademark, warning text and other signs.

2. Choose lenses

When choosing lenses, it is best to choose polarized lenses. The lenses of polarized sunglasses can prevent glare. When purchasing sunglasses, consumers can request polarization test card from optical stores. In the case of polarized sunglasses, the pattern will change when the sunglasses lens is facing the test card. In the absence of a test card, consumers can slowly rotate the sunglasses 60 degrees in front of the computer screen to observe whether the lenses change during the rotation. If you wear polarized sunglasses, the picture will change from bright to dark. Try to choose the three colors of black, brown and gray for the lens color, which can have a good light filtering effect. If you are short-sighted, it is recommended to wear a sun visor clip.

3.  Use banknote detection lamp

In the absence of professional testing equipment, consumers can observe the UV protection effect of sunglasses by using small tools such as banknote detectors to illuminate the watermarks on banknotes through sunglasses. The more obvious the watermark is, the weaker the UV protection function of the sunglasses will be.

4. Try on sunglasses

When purchasing, consumers can try on the sunglasses to see if there is any dizziness or headache. When choosing frames, consumers can pay attention to the appearance and feel of the frames. Comprehensively judge the quality of the frame from aspects such as the frame's spring recovery, temple opening flexibility, screw tightness, and solder joint technology, and observe whether the frame and temples are twisted or loose.