Human beings have been wearing sun-blocking eyewear for nearly 2,000 years. Fortunately, we have access to technology today that far outshines the methods used all those years ago. However, that also means that there is a wide variety of options available, from the toughness of athletic sunglasses to the stylishness of photochromic lenses. When it comes to sunglasses that are both durable and lightweight, there are only two main choices: polycarbonate shatter-resistant sunglasses and Trivex sunglasses. Let's compare and contrast the two based on their primary qualities.
- Thickness: Polycarbonate lenses have a higher index of refraction than Trivex lenses, but not by much (1.58 vs 1.53). This translates to a lens that is around 10% thinner.
- Weight: Despite having less material due to the thinner lens, polycarbonate sunglasses are heavier than their Trivex counterparts. Trivex lenses are composed of a urethane-based monomer that has lower specific gravity than polycarbonate and is 10% lighter as a result. If you're going to be racing, hiking, or running, you don't want to feel the sunglasses on your face.
- Impact Resistance: Due to their manufacturing process, both lenses are suitably shattered resistant and scratch-resistant. If your main concern is what will happen if your glasses get dropped, you won't need to worry about either option.
- UV Protection: Both Trivex and polycarbonate lenses offer 100% UV ray protection -- without the need for special UV-blocking coatings.
- Optical Clarity: All lenses are given an Abbe number which describes the amount of chromatic aberration (which describes the occurrence of problems such as distorted or blurred images) of an optical lens. Trivex lenses have a higher Abbe value so they can produce both sharper central and peripheral vision with less chromatic aberration than polycarbonate lenses. Basically, your vision will be clearer and contain fewer distortions with Trivex lenses.
Whether you're climbing Mount Everest or mountain biking in Colorado, you're going to need sunglasses that can keep up with you. It's clear from the above comparison that Trivex is the way to go; though polycarbonate shatter-resistant sunglasses are dependable in their own right, they cannot provide the same optical and lightweight benefits of Trivex that are needed in highly active sporting scenarios.