The non-reflective coating, also known as the antireflective coating or anti-glare treatment, is a transparent layer of magnesium fluoride, which is usually applied to both sides of the lens. Sometimes, non-reflective coatings are applied to only one side of the lens at the customer's request.
The layer limits the reflection of light which allows the maximum amount of light to pass through the lens. A non-reflective coating is effective for reducing the brightness of the headlights or halo effects and helps reduce visual fatigue when using a computer. This means that the user's eyes will be less tired at the end of the day dedicated to focusing on a computer monitor. Another benefit of coating is to make the lens look more pleasing cosmetically by reducing or eliminating reflections.
Although non-reflective coatings clearly have benefits, these coatings also have several disadvantages. A non-reflective coating can make the lens look green or blue. Non-reflective coated lenses are harder to clean and are known to be easily stained. Something as simple as someone's eyelashes that rub lightly on the back of the lens can cause blur.
Like other industries, when technology increases, the product too. This also applies to non-reflective layers. Because of technological advancements, there are various levels of coatings available to meet everyone's needs.
The standard level is considered the lowest level and the points are easy and often. This is one of the main reasons why this is the cheapest. Ultra and premium levels are the highest and most expensive levels. They reduce the frequency of spots, they are more resistant to scratches than standard levels, which makes it more attractive and effective for users. They reflect less than the standard level and allow the maximum amount of light to pass through the lens.
There is more than one application process for applying a non-reflective coating on the surface of the eyeglass lens. One process is to spray the coating and then expose the lens to high temperatures for long periods of time, which causes the liquid solution to harden and attach to the lens.
Another process is a type of vacuum application where the lens is placed inside a large machine and then coated with liquid. The vacuum process combined with very high heat results in a hard non-reflective scratch-resistant coating attached to the lens.
The third process of how the non-reflective layer is applied to the lens is in the manufacturing process when the lens is produced. The actual layer is integrated into the material and distributed throughout the lens.
If the non-reflective layer is damaged or scratched, the layer can be removed. This will eliminate any discoloration caused by cracking or scratching, making the lens practically new to the user.