Founded by Giuseppe Ratti in 1917, Persol is a brand of glasses designed for pilots and race car drivers and is now known for its durable sports sunglasses. Persol is an Italian luxury eyewear brand specializing in the production of sunglasses and frames. It is one of the oldest eyewear companies in the world, originally catering to pilots and sports riders. Currently, the company sells durable sports sunglasses. Currently, all Persol plastic glasses are made in Italy using cellulose acetate. Persol has had an apparent influence in the sunglasses industry. It was Persol who pioneered the development of elastic frames.
Are carbon fiber glasses better or titanium?
In terms of weight, the titanium frame is very light. The specific gravity of the pure titanium frame is about 4.5g/cm3, and the specific gravity of the titanium alloy frame is about 8.9g/cm3. The pure titanium frame is lighter than the titanium alloy frame. However, carbon fiber glasses are lighter in weight. The carbon fiber glasses launched by LOHO are only 7.87g, which is very light to wear.
In terms of hardness, titanium has a high hardness, about twice that of stainless steel, twice that of iron, and six times that of aluminum. Carbon fiber is lighter than aluminum, harder than steel, and its strength is ten times that of iron.
In other respects, the titanium frame has the advantages of corrosion resistance, acid and alkali resistance, high stability, good elasticity, good toughness, and resistance to deformation. The carbon fiber frame has the advantages of corrosion resistance, high temperature resistance, radiation resistance, good elasticity, good flexibility, and abrasion resistance.
It can be seen from the above comparison that carbon fiber glasses have the general advantages of titanium frames. In terms of weight, carbon fiber glasses are much lighter than ordinary pure titanium glasses.
Which is better, MR7 lens or MR8 lens?
The refractive index of MR7 is 1.67, and its Abbe number is 32, so it has a good dyeing property. MR8 has a refractive index of 1.60 and an Abbe number of 40 or more. MR8 has stronger toughness, so it is more tensile and is not easy to break when confronted with strong impact. The lenses of MR7 and MR8 are different in the degree of heat resistance, and the heat resistance of MR7 is slightly weaker. MR7 is recommended if you want thinner and lighter lenses, but MR8 is recommended if you want higher light transmittance.
Eyewear stores are close to consumers.
Location is a very critical factor. A reason why customers can walk into your store is that if it is convenient to go to your store. If there are two stores of the same size, your store is in front of the school gate and the other one is 500 meters away from the school, then your store will definitely attract more customers than the one 500 meters away.
About the early domestic anti-reflection coating lens
Chinese coated lenses appeared in the mid-1980s. At that time, Europe (such as France and Germany) and Asia (such as Japan, Singapore, and Taiwan) had already launched coated lenses to the market, and the grade of lenses was evaluated based on the quality of the anti-reflection effect. Among them, Germany and France were the two leading countries in technology. Technically, the use of French original film material (referred to as H2) can reduce the effect by 99.98% (refers to the light transmittance, the same below). Almost you can not see the reflection, but the material is expensive. Therefore, the coating lens which is currently used in the world is born. The anti-reflection effect is controlled at about 98%, so the coating cost is greatly reduced. And it is accepted by consumers because it presents various colors, especially green. At the same time, because at the same time, it can be easily distinguished from non-coated lenses. It can reflect the high-grade film lens, and it is accepted by the sales staff.
The disadvantages of progressive lenses
- The field of view in the near and middle distances is relatively narrow.
- The adaptation time is longer and patients with greater astigmatism are not suitable for wearing.
- The peripheral aberration is large, and there will be large astigmatism in the periphery.
What Are Polycarbonate Lenses?
Polycarbonate lenses are made from a type of plastic that is famous for its durability. Polycarbonate lenses are perfect for those who are doing sports while wearing glasses. It is also used in children’s glasses since kids are much less careful with their glasses than adults.