Fuse Pro: All About Polycarbonate Sunglass Lenses

 Polycarbonate has become a staple in the eyewear industry because of its relatively low cost and extreme shatter resistance, but if you have polycarbonate in your sunglasses, what can you expect? 

What is Polycarbonate?

Polycarbonate is a transparent and strong thermoplastic used most often in the optical industry, but sometimes you can find it being used in the engineering field. Before making its way into your sunglass lenses, polycarbonate was most commonly used in the visors on astronauts helmets, and eventually earned itself the reputation of being a strong, scratch resistant, and reliable material for eyewear. Polycarbonate comes in both injection, and bent sheet form (which we’ll cover later) , and either type is extremely shatter resistant and tough, making the perfect material for a pair of lenses. 

What to Look for in Your Polycarbonate Sunglasses

Some people are hesitant to make the switch to polycarbonate lenses. It’s a similar material to plastic, which can be off-putting for those looking for high quality lenses. So what should you be focusing on when looking for polycarbonate lenses? Let’s break it down.  

All About Optical Grade

When looking into lenses, it’s important to realize that not all polycarbonate lenses will be the same quality. That’s where optical grade comes in. Optical grade is basically whether or not the polycarbonate is clear enough and durable enough to be considered for prescription purposes.   Optical grade comes hand in hand with something called refractive index. The refractive index is the ability of the lens to bend light. It ranges from 1.5 being the standard index, to high index at 1.75. Quality polycarbonate has a refractive index around 1.58, making it a high index material. Plastic has the lowest refractive index, which is why plastic lenses are generally cheaper and lower quality.   

Injection vs. Bent Sheet Polycarbonate

As mentioned earlier, there are two different types of polycarbonate, injection and bent sheet. Injection polycarbonate is what we use at Fuse. It’s easier to mold into your desired shape, but just because it's easier doesn't mean its lower quality. Injection polycarbonate is the higher quality of the two options. Bent sheet polycarbonate is harder to mold, since it’s already starting off as a solid and requires you to break it into your desired shape. Bent sheet also needs to be at a very specific temperature before you can break it. Because of the process of making bent sheet polycarbonate, the lenses are more prone to peeling or falling apart, and are generally just worse quality than injection. 

TAC vs. Polycarbonate Polarization 

You might have heard of a material called Triacetate (or TAC) that's commonly used in optics. Or, if you haven’t heard of it - you’ve definitely looked through them. TAC lenses are the cheapest widely used lens option in sunglasses and are less clear, less scratch resistant, and less durable than Polycarbonate. Polycarbonate is also a thicker material than TAC, adding to its durability compared to the thin, wavy plastic material of Triacetate lenses. Polycarbonate is also more durable than  plastic, and more shatterproof than glass,  making it the obvious choice when buying lenses. 

Where can you find High-Quality Polycarbonate Sunglass Lenses?

If you’re looking for lenses that will last long, are durable enough to withstand any weather conditions, and will give you the clarity you deserve, Polycarbonate is definitely the way to go. But where can you find these kinds of lenses? Come check out Fuse's new Fuse Pro lenses,  Here you can find high quality polycarbonate lenses for any brand name frames, or you could choose from our various styles of frames for a fully new pair of quality sunglasses.