Choosing a good lens can be seriously tough. People usually don’t know much about the material and coatings. So, anything their optician recommends they go for it. Well, one should know about different types of materials and coating used in the lenses. While your optician may suggest you anything for the price, knowing about the best options will certainly help you make the right choice. Here, we will discuss different types of lenses in terms of materials and coatings, and which are the best lenses for glasses.
4 common materials
There are 4 different materials used in the manufacturing of lenses for glasses. These include the basic material known as CR-39, Lightweight and impact-resistant polycarbonate, trivex that has an additional property of optics along with the features of polycarbonate, and high index that is the thinnest and lightest of all.
CR-39 is the basic lens material that has an index of 1.50. Traditionally, all the glasses were made using this material and it was pretty good considering its functioning. However, the fact that this material was easily breakable and made frame pretty heavy forced manufacturers to look towards other options. Soon, lightweight CR-39 was also introduced in the market and came as an affordable option. However, still, the impact resistance was facing questions and the thickness was another issue faced commonly by people with weaker vision.
So, to address the heaviness and thickness of CR-39, polycarbonate was introduced in the market. It has an index of 1.59 and has a fairly good resistance to impact. The fact that these glasses are thinner and lighter made it a preferred choice for many people. What else? These lenses had a 100% UV filtration and the protection was built-in so manufacturers didn’t have to apply any additional coating.
Trivex comes at the index slightly lower than polycarbonate i.e. 1.54. However, it shares the majority of the features of polycarbonate and offers better optics. They were initially made for military helicopters and jets. However, the optics were developed with it in the early 2000s. Till today, trivex stands as the most lightweight material for lenses and offers great resistance to impacts. Moreover, like polycarbonate, it has 100% UV protection built into it.
What makes it a touch superior to the aforementioned type is its crisper and better optics. The process of manufacturing this material is excellent and this gives trivex clearer vision as compared to other choices.
As the name suggests, this material is known for its index power that stands between 1.67 and 1.74. These lenses are the best lenses for people with extremely weak vision. Glasses made with the above-listed materials, particularly with CR-39 and trivex, can be chunky and big. However, high index frames offer lighter and thinner lenses for people with a prescription of around -6.00+. However, the impact resistance is not as good as trivex or polycarbonate lenses.
5 popular coatings
Once you are done with the selection of the material for your lens, the next thing to consider is coating. Different options are available that offer you protection in various ways.
When you opt for lightweight glasses, the surface is soft and there is no doubt that scratches can be visible with the passage of time. So, to add durability to the lens, manufacturers apply anti-scratch coatings. The modern-day scratch coating, also known as the hard coat, can help in making your plastic frames as prone to scratches as a glass. However, you must not end up being harsh when it comes to the usage, or else a few scratches may become visible.
Next up we have an anti-reflective coating which is one of the most popular choices. The AR coating helps in improving the contrast and clarity by eliminating the reflections which many individuals suffer from as they wear glasses. Particularly at night, when the light hits your glasses, the reflections can cause serious trouble. Thus, AR reflection should never be overlooked.
It is essential if you are using high-index material because of its greater refraction power as a high index can reflect as much as 50% more light as compared to a CR-39 lens.
The exposure to harmful radiation coming from the sun can damage your skin as well as your vision. Therefore, you need appropriate protection against it and UV layering can come to your assistance. However, not all the materials require these coating as polycarbonate and trivex come with built-in 100% UV protection. Just be cautious about this as you choose CR-39.
This treatment darkens your lens as you go out in sunlight or are exposed to high energy visible light rays. The lens will turn back to clear as you move indoors in the appropriate light.
Blue light protection
Another decent coating is blue light protection. It can be seriously helpful for people who have long exposure to digital screens. This layering filters out blue light and protects your retina.
Choosing the best one
Which one is the best? Well, this is a question that only you can answer. Make sure to read all about the material and coating and then pick a lens that satisfies your requirements the best.