What lenses do sunglasses have?

Sunglasses can have different types of lenses, each with its own benefits and uses. Here are some common types of sunglass lenses:

1. Polycarbonate lenses: Polycarbonate lenses are lightweight and impact-resistant, making them a good choice for sports or other activities where durability is important.

2. CR-39 lenses: CR-39 lenses are a popular choice for sunglass lenses because they're lightweight and offer good optical clarity.

3. Glass lenses: Glass lenses provide excellent optical clarity and scratch resistance, but they're heavier and more fragile than other lens materials.

4. Polarized lenses: Polarized lenses are designed to reduce glare and improve clarity, making them a good choice for activities like driving, fishing, or skiing.

5. Photochromic lenses: Photochromic lenses, also known as transition lenses, darken automatically in response to sunlight or UV rays. They're a convenient option for people who spend a lot of time outdoors, as they can provide both clear and tinted vision in changing light conditions.

6. Gradient lenses: Gradient lenses are darker at the top and lighter at the bottom, providing protection from the sun while allowing for clear vision at the bottom of the lens.

7. Mirror-coated lenses: Mirror-coated lenses have a reflective coating that reduces the amount of light that enters the eye, making them a good choice for bright or sunny conditions.

8. Prescription lenses: Prescription sunglass lenses can be customized to your individual vision needs, providing both visioncorrection and sun protection.

It's important to choose the right type of lens for your needs to ensure that you're getting the best vision and sun protection possible. Consider factors like the activities you'll be doing, the amount of time you'll be spending outdoors, and any vision correction needs you may have to help you choose the right type of lens.