Hi-Index-These lenses are by far the thinnest choice available. They are available up to forty percent thinner than CR-39 and are the best suited for high prescriptions. Though hi-index lenses are the thinnest, they are not as lightweight as polycarbonate or trivex. Hi-index lenses come with built-in ultra-violet protection, but are not impact-resistant. They can be coated to reduce glare and increase scratch-resistance, or be tinted for sunglasses.
Hi-index lenses are the most expensive, and usually must be special ordered. They are not suited for children or athletes. Hi-index is recommended for those who are tired of thick, unattractive spectacle lenses and don’t mind the added cost.
The least expensive lens choice is CR-39 plastic. All of the thinner and lighter materials are manufactured using advanced technology and will be more expensive.
The most widely available and least expensive thin, light lens is polycarbonate. This material is stocked in most one-hour shops, boasts excellent scratch-resistance, and has a proven track record of great performance.
If your current spectacle lenses magnify or distort the appearance of your eyes, try lightweight lenses in your next pair. These lenses almost always improve the appearance of your eyewear and minimize the negative effects of a strong prescription.
Lightweight lenses will also improve the comfort of your eyewear. Heavy lenses can cause red indentations on the bridge of the noise or painful pinching behind the ear, often leading to headaches.
Eyewear should be comfortable, attractive and suited to your individual needs. With the many lens choices widely available now, every prescription can be customized to suit the wearer’s needs perfectly.