progressive multifocal reading glasses that are resistant to strong sunlight and harmful and do not change color under artificial light or indoors

Many customers have commented that their eyeglass lenses do not discolor, and the reasons are: 1. Outdoor lenses become dark gray in strong sunlight but do not discolor under artificial light; indoor lenses do not discolor. 2. Outdoor lenses become light gray in faint sunlight, and the discoloration is not noticeable. 3. Lenses do not discolor outdoors in cloudy conditions or when not exposed to sunlight; indoor lenses do not discolor. The principle of eye protection through lens discoloration: 1. To protect the eyes from ultraviolet rays outdoors, the lenses change color in response to sunlight. The stronger the sunlight, the stronger the UV rays, the faster the lens discolors, and the darker the color becomes. 2. On days with weak outdoor sunlight, cloudy or rainy days, or days with weak UV rays, the lenses do not become light gray or discolor. 3. Indoor lighting does not produce UV rays, so indoor lenses do not discolor. Three uses for eyeglasses: 1. The middle and upper parts of the eyeglasses have a slight prescription and are used to see things at a distance. 2. The central part of the eyeglasses is used when keeping the eyes flat, such as when watching TV or using a computer. 3. The middle and lower parts of the eyeglasses have their own prescriptions (for example, if you buy +150 eyeglasses, the lower part will have a +150 prescription) and are used for reading. When using these bifocal reading glasses for the first time, it usually takes about a week to get used to them. However, bifocal reading glasses are not suitable for everyone. If you are not satisfied with the quality, you can submit a return request within 30 days and receive a full refund. Many customers have commented that their eyeglass lenses do not discolor, and the reasons are: 1. Outdoor lenses become dark gray in strong sunlight but do not discolor under artificial light; indoor lenses do not discolor. 2. Outdoor lenses become light gray in faint sunlight, and the discoloration is not noticeable. 3. Lenses do not discolor outdoors in cloudy conditions or when not exposed to sunlight; indoor lenses do not discolor.