It is normal for spectacle lenses to have fog and engravings. This is the anti-counterfeiting mark of brand lenses. It has no impact on the clarity, visual effect, light transmittance, and corrected vision of the lenses. In addition, the engravings are generally on the edge of the lenses. , away from the central optical zone of the lens. Essilor lenses have an invisible anti-counterfeiting mark (fog display mark - Crizal). When the protective film is not wiped off the Essilor lenses, you will be relieved and "Crizal" will be displayed on the lens (except for blue crystal). There is a haze mark - Crizal within 2cm in diameter near the optical center of Diamond Zhijie and all progressive lenses. You can judge it by breathing. However, if there is astigmatism and the ground lens is very small, this mark may be rubbed away after processing; generally All can be retained. If there is astigmatism, this mark may not be left on, but if there is no astigmatism, it can definitely be left on. You can call and ask whether the anti-counterfeiting mark was removed during processing. How to identify the anti-counterfeiting of Zeiss lenses. First, the anti-counterfeiting of Zeiss lenses is not displayed without fog, but can be seen directly, close to the edge of the lens. How to identify anti-counterfeiting lenses? If you buy rough lenses, you can keep them for 100 yuan. Single vision lenses can be kept after assembly. After assembly, the anti-counterfeiting marks of astigmatism lenses may be worn away. The anti-counterfeiting mark of the lens can be seen through the reflection of the lens. Second point, all Carl Zeiss lenses will have laser anti-counterfeiting marks, which are shaped like two small flags put together. Laser anti-counterfeiting marks are difficult to imitate, and each lens has an original warranty card.