Types of aspheric lenses
There are two types of aspheric lenses: single aspheric surface (single aspheric surface for short, different from the outer aspheric surface and inner aspheric surface) and double aspheric surface (double aspheric surface for short). For the outer aspheric surface, convex is an aspheric surface and concave is a spherical surface. For the inner aspheric surface, a convex surface is a sphere, and a concave surface is an aspheric surface. In addition to correcting aberrations, the double aspheric lens also improves the effective field of vision compared to the single aspheric surface. When people's eyes look through the edge of the lens to see things, like driving when looking at the reflective mirror, it often affects vision because of the large aberration at the edge of the lens. Previous designs of aspheric plates have analyzed a single ray of light passing through the center of the pupil. Wavefront technology controls the entire beam of light passing through the pupil, eliminating high-order aberrations.
Armada Optical Services
Armada Optical Services is a full-service laboratory dedicated to providing one of the best safe prescription eyewear programs for your organization. They now have different kinds of safety frames, including plastic, stainless steel, frameless, and titanium. Armada provides all the safety lenses available on the market today, including special lenses for welding, furnaces, etc. The company has certified polycarbonate and Trivex (Trilogy) lenses to meet the new ANSI Z87.1-2003 standard. They provide a variety of high impact lenses. Armada is the laboratory for safety, quality, price, selection, service, and knowledge.
Can lens thickness affect eyeglasses definition?
The lens thickness of myopic glasses will not affect definition, so you can choose the glasses with appropriate degrees according to your own situation. It is recommended to choose the lens with a membrane, which can increase the transmittance and can play the effect of anti-ultraviolet and waterproof functions. The thickness of the lens is related to the refractive index of the material used in the lens. The higher the refractive index of the lens, the thinner it is. The so-called ultra-thin lens is the lens with a high refractive index. From the side view of the lens, there will be a fuzzy color phenomenon. Because the nearsighted lens is a concave lens, and the edge is similar to a prism, which can produce a prism effect. In addition, when you wear glasses, try to choose a smaller frame, so you can avoid the prism effect on the edge of the lens.
The refractive index of lens
Refraction law is discovered by Dutch mathematician Snell.It is the law that determines the direction of refracted light in the phenomenon of light refraction. When the light from the first medium (refractive index N1) into the second medium (refractive index N2), part of the light from the first medium into the second medium at the smooth interface will be refracted. The index of refraction is the ratio of the speed at which light travels in a vacuum to the speed at which light travels in the medium. For glasses lenses, the higher the refractive index, the thinner the lens, that is, the lens with the same center thickness and the same degree, the lens with the higher refractive index has thinner edges than the lens with the lower refractive index of the same material.
Why should children be more vigilant about harmful blue lights?
The amount of light transmitted to the retina through media such as the cornea, lens, and vitreous is age-related. Blue light poses the greatest risk and damage to the eyes during adolescence. As our eyes' refractive media naturally yellows, more blue light is absorbed, preventing it from reaching the retina. The lens transmittance of children under the age of 10 is more than six times higher than that of adults. It is important to prevent the damage of blue light to children's visual health.
Round Glasses
While round glasses have been popular for the past few years, this season, metallic round frames from the '80s and 90s are getting more attention. These days, round glasses aren't just for Harry Potter fans. People add a sense of weirdness or fashion to their appearance. If you have an angular face and a chiseled chin, then round glasses are for you.
Advantages Of TR90 Frames
- Lightweight. The weight is about half the weight of the plate frame, which can reduce the burden on the bridge of the nose and ears, and it is also comfortable to wear for a long time.
- Bright colors. Compared with ordinary plastic frames, the color of TR90 frames is even better.
- Impact resistance. The TR90 frame is extremely flexible, and its good elasticity can effectively prevent damage to the eyes caused by impact during sports.
Regardless of whether it is a sheet frame or a TR90 frame, they have their own advantages. You can choose them according to your requirements, Importantly, it is comfortable to wear and good-looking.
