What is the best material for sun lenses?

The material of the sunglass is more important than the shape and color. Good sunglass should not only have a gorgeous appearance, but also have lenses with good anti-ultraviolet and anti-glare functions, as well as a certain anti-impact performance. And these functions are determined by the material of the sunglasses lens. Sunglass lenses can be divided into plastic lenses, glass lenses, polarized lenses, color-changing lenses, resin lenses, PC lenses, acrylic lenses, etc. The following is a brief introduction to sun lenses of different materials. 

1. Glass lenses

 The most prominent advantage of glass lenses is that their optical performance is very stable.Glass lenses are not easily deformed and will not be affected by the pressure of the frames. The disadvantage of glass lenses is that they are easily broken, which can easily cause damage to the eyes. At present, the newly developed strengthened glass lens has much more outstanding performance than ordinary glass lenses, and is is regarded as a safety lens.

2. Polarized lenses

This is used in polarized sunglasses. It uses the polarization principle of light to block glare from all sides from the lens, making the sight clearer and safer when driving. In 1937, Edwinland Bausch & Lomb in the United States invented this kind of lens, and then it was widely used in polarized sunglasses. He then created his own polaroid company.

3. Color-changing lenses

Also known as photosensitive lenses, the color of the lens will change accordingly due to the change of light, so that the eyes can adapt to different environments. Under strong light, the color of the lens will deepen,while under the light the color of the lens will automatically become lighter.  This type of lens has been used in myopia sunglasses, and it is also considered to be the most convenient and beautiful type of myopia sunglasses, more popular than the clip-on type.

4. Plastic lenses

 Its obvious feature is that it is light and unbreakable. The anti-ultraviolet function of plastic lenses without any treatment is significantly better than that of glass lenses, and the color processing of plastic lenses is also simpler. The disadvantage of plastic lens is its poor wear resistance, it is easy to be scratched, and it is easily deformed when it is hit.

At present, there are mainly three kinds of plastic material lenses. They are resin lenses, PC lenses, and acrylic lenses.

5. Resin material sunglasses lenses

Resin (CR-39) is actually a chemical substance with a phenolic structure. It is extracted from phenolic components in petroleum. It is with light weight, high temperature resistance, strong impact resistance, and can effectively block ultraviolet rays,etc. The great advantage of resin lenses used in sunglasses is their easy tinting properties. Many fashionable sunglasses use the properties of resin lenses that are easy for tinting. However, the resin lens has poor toughness and is not resistant to impact. This type of sunglasses lens is widely used. It has a strong decorative effect and it's a good choice for fashion people.

6. PC material sunglasses lenses

PC refers to polycarbonate, which is a kind of plastic (PC for short), it is a polymer containing carbonate groups in the molecular chain. PC material lenses are simply plastic sunglasses lenses. This material has high-end and low-end types. It is characterized by lightness and good coloring properties, but its disadvantages are low abrasion resistance and unstable optical performance. Sunglasses made of PC material are more suitable for sports people and drivers.

7. AC lenses (acrylic lenses)

It has excellent toughness, high transmittance, good anti-fog function, lowest cost. But The material is brittle, and there may be brittle chips when cracked, optical stability is not good enough.

8. Nylon sunglasses lenses

Nylon sunglasses are mostly used in sports brand sunglasses and high-quality big brand sunglasses. They have high elasticity, excellent optical quality, and strong impact resistance. When nylon lenses were invented, they were used as eye protection glasses since they have professional protection function. However, nylon lenses have poor wear resistance and high production costs. This type of lens is more suitable for sports sunglasses or professional protective sunglasses.

9. TAC material sunglass lenses

TAC (Triacetyl Cellulose), its composition is very complex. It is one of the high penetrating polymer materials. TAC has the characteristics of acid and alkali resistance, light and thin texture, and high cost performance. However, the wear resistance is poor, and the optical properties are not stable.