Three High Index Lens Myths: The Facts
There are a lot of opinions about high index lenses out there. Some are accurate while others are off the mark. While freedom to express one’s views online is a good thing, it can create confusion that gets in the way of making an informed purchase. Sometimes hearsay can cause harm or it may steer people away from benefits and opportunities that improve lives. Here are three misconceptions about high index lenses:
Strong Prescription Glass Lenses Are Thick
Up until the mid 20th century, glass was the only lens material used for glasses. That changed with the introduction of CR-39 plastic lenses, which were far lighter and much more resistant to shattering. The optical quality was inferior to glass but still reasonably good.
CR-39 plastic lenses became very popular in the 1970s and from then on, plastics displaced glass as the lens material of choice. Lots of advancements were made in plastic lens materials over the years, which led to the incredible plastics used in high index glasses. Plastic 1.67 and 1.74 high index lenses are very thin and lightweight, and bear no resemblance at all to the old coke bottle lenses made from CR-39 or crown glass.
However, while this progress was happening with plastics, glass lens technology didn’t stand still. Many advancements were made over the years. In fact, thin 1.8 and 1.9 high index lenses are available in glass. They are fairly tough and impact resistant, though not on a par with plastics such as polycarbonate. These lenses are thin and fit on many stylish frames. However, they aren’t as light-weight as plastic. In any case, strong prescription glass eye-wear need not use thick coke bottle lenses.
High Index Lens Reflections Interfere with Vision and Make Driving Dangerous
This myth is true and false. Plastic high index lenses do reflect about 50% more light than ordinary plastic or glass lenses. The reflections can interfere with your vision especially when night driving. However, this difficulty doesn’t exist when you use them with an anti-reflective (AR) lens coating. An AR coated high index lens transmits up to 99.5% of light to your eyes. This allows unimpeded vision when night driving without lens induced glare.
High Index Lenses Aren’t worth the Money
Although high index lens costs are significantly higher than standard CR-39 plastic, the price of 1.67 and even 1.74 high index lenses are comparable to the cost of a quality pair of jeans. The alternative to these lenses is thick and heavy lenses made from either standard plastic or standard glass. These lenses distort your eyes, are heavy, and feel uncomfortable to many people.
In contrast, high index lenses are thin, lightweight, and don’t distort your appearance. They fit on a wide variety of frame styles. If you want to make a style statement, you can get thick plastic frames such as nylon. On the other hand, you can minimize the impact of your glasses on your appearance by purchasing rimless styles with thin light-weight metal frames. This feat is impossible with thick lenses. Another consideration is that high index lenses are a one-time cost and will last for years.
High index lenses allow you to more easily live a physically active life. They fit on frames designed for different sport activities. The less weight on the bridge of your nose, the more comfortable the glasses feel when engaged in activity involving lots of physical movement. A heavy pair of glasses may tend to slide down the nose when running, for example. While you can solve this problem with a band that holds them in place, the lens weight still feels uncomfortable and may cause nose indentations.
You also can’t take advantage of frame styles such as wraparounds that maximize eye protection from UV, wind, and dust. These design differences enhance your performance and give you the edge in sport events involving competition.
Finally, high index lenses with the right frame style give you a new look that can boost your career. Appearances and impressions are important in the business world — a fact that won’t change anytime soon.