Lens material of sunglasses：The prices of sunglasses are vastly different. In addition to the price determined by the brand, there are also lens materials. Lenses can affect optical transparency, weight, durability, and cost. Recommended reading: choose sunglasses should also be rational consumption
Polycarbonate material: it can block 100% ultraviolet rays by itself, and does not need lens coating. Impact resistance and transparency are very good, second only to polyurethane. It is cheap, light and non friction, so it also needs to be coated.
Polyurethane material: maximum impact resistance and best optical transparency. Elastic, light and expensive.Frame material of sunglasses。Metal frame: stainless steel, aluminum alloy and ultra expensive titanium alloy. Very light, but not suitable for high-intensity sports. Metal frame sunglasses are cool and temperament to wear, but wearing sports is a little different. In hot summer, the metal frames of sunglasses placed in the car will become very hot and cannot be worn immediately.
Nylon frame: inexpensive, lightweight, and more durable than metal frame. Many goggles and sports sunglasses are made of nylon, and the radian of the nylon frame cannot be adjusted unless there is a steel wire core inside the frame.
Acetate lens frame: expensive, lightweight, diverse color changes, poor ductility, can not be used for sports wear.Visible light transmittance of sunglassesAs the saying goes, the color depth is the same. Looking at the following figure, you will find that sunglasses of the same color have different depths.
This performance is called visible light penetration, which has a level of 0-4. The weather and place of wearing vary with the depth: grade 0, indoor and cloudy; Grade 1-2, medium and low brightness sunlight, sun protection for driving and urban life, fashionable sunglasses belong to this kind。
Most sunglasses are grade 3, which can be worn in strong light (seaside, mountaineering); Grade 4, extremely strong sunlight (snow mountains, deserts, mountains, waterside), can't be worn when driving or cycling, and the field of vision is too dark.
Lens color of sunglassesAccording to different weather, choose the following:Please tell me that sunglasses worn during sports are specially designed. There is a non slip nose support, which fits more firmly. There is a surround frame, which can block the reflected light from the side. The color of infant sunglasses can be brown or gray. Gray lenses provide more natural visual quality, but brown lenses can filter harmful short wavelength blue light. I personallyrecommend choosing brown.