Features of Various Lenses with Different Functions
1. The quality of the substrate
The quality of the substrate determines the durability of the lens and the reliability of the coating. A good substrate is clear and translucent, has a long time of use and is not easy to turn yellow; and some lenses turn yellow after a short period of time, and even the coating falls off. The good lens has no scratches, abrasions, rough surfaces, or pits. The lens is obliquely facing the light, and the finish is extremely high. There are no spots, stones, streaks, bubbles, cracks inside the lens, and the lens is bright and transparent.
2. The grade of the lens
Mass-produced lenses are classified into different grades due to the difference in inherent quality, and the prices of superior products and inferior products are very different.
3. Refractive index
The higher the refractive index of the lens, the thinner the thickness and the higher the price.
4. Coating and anti-ultraviolet treatment
The resin sheet can be coated with more than a dozen layers of hardening, anti-reflection, anti-static, dustproof, and waterproof. Different coating treatments have different effects. If the coating process is reduced, the quality of the lens will be greatly reduced. Similarly, if you wear non-UV-resistant lenses as UV-resistant lenses, it is very harmful to your eyes.
5. Test the transparency and optical uniformity of the lens
Hold the lens about 30 cm away from the eye, and observe the distant scene through the lens. If the scene is clear and without distortion, and there is no scene jumping when the lens is moved slowly, the transparency and optical uniformity of the lens are good.
6. Wearing feeling
There is no feeling when wearing, no dizziness or swelling, no obscurity or deformation of the observed object. When buying, hold the glasses, see through the lens with one eye, and shake the lens up and down, so that the distant objects should not have the illusion of movement.
7. Protection
High-quality lenses can effectively block ultraviolet rays and provide effective ultraviolet protection for wearers.
The quality of the substrate determines the durability of the lens and the reliability of the coating. A good substrate is clear and translucent, has a long time of use and is not easy to turn yellow; and some lenses turn yellow after a short period of time, and even the coating falls off. The good lens has no scratches, abrasions, rough surfaces, or pits. The lens is obliquely facing the light, and the finish is extremely high. There are no spots, stones, streaks, bubbles, cracks inside the lens, and the lens is bright and transparent.
2. The grade of the lens
Mass-produced lenses are classified into different grades due to the difference in inherent quality, and the prices of superior products and inferior products are very different.
3. Refractive index
The higher the refractive index of the lens, the thinner the thickness and the higher the price.
4. Coating and anti-ultraviolet treatment
The resin sheet can be coated with more than a dozen layers of hardening, anti-reflection, anti-static, dustproof, and waterproof. Different coating treatments have different effects. If the coating process is reduced, the quality of the lens will be greatly reduced. Similarly, if you wear non-UV-resistant lenses as UV-resistant lenses, it is very harmful to your eyes.
5. Test the transparency and optical uniformity of the lens
Hold the lens about 30 cm away from the eye, and observe the distant scene through the lens. If the scene is clear and without distortion, and there is no scene jumping when the lens is moved slowly, the transparency and optical uniformity of the lens are good.
6. Wearing feeling
There is no feeling when wearing, no dizziness or swelling, no obscurity or deformation of the observed object. When buying, hold the glasses, see through the lens with one eye, and shake the lens up and down, so that the distant objects should not have the illusion of movement.
7. Protection
High-quality lenses can effectively block ultraviolet rays and provide effective ultraviolet protection for wearers.
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