What Are High Index Lenses?
High index lenses are eyeglasses lenses that are designed to be thinner and lighter than regular lenses. High-index lenses have a high refractive index than their conventional counterparts. High index lenses are recommended for people who have significantly high refractive errors and strong prescriptions for nearsightedness, farsightedness or astigmatism.
High index lenses are thinner, lighter and more appealing than standard lenses, but they come in several different indexes such as 1.67 high index lenses and 1.74 high index lenses. In this post, we will focus on the 1.67 high index lenses and 1.74 high index lenses.
What are polarized lenses for?
Polarized lenses contain a layer of polarizing plates in which molecular chains form a light-grating structure in which dichromatic pigments, which absorb polarized light, are evenly distributed. A beam of light is absorbed when it vibrates in the same direction as the bars of the molecular chain of the polarized lens. The grating direction formed by the molecular chain of the polarizer is the axial direction of the polarizer, which is generally horizontal. When polarized lenses are worn, they absorb all the light that vibrates horizontally, thus absorbing the glare and preventing it from reaching the eyes.
The shape of the lens is also important.
Aviator and cat-eye glasses should be avoided, as both will cut off the base of the prescription, resulting in poor reading vision. Instead, they should opt for shorter frames with rounded edges, such as bull horn frames, vintage wingtips, round frames, and oval frames.
Choose Quality Merchants
Online shops are of all kinds, from different parts of the country. We need to find a professional and reputable shop, with the help of some small skills. For example, from the purchase of some users of the use of evaluation, store credit rating, store introduction, and other aspects, we determine the overall situation of the store and finally buy in this store.
Design principle of aspheric lens
Early optical lenses use spherical lenses. Because the glasses were small round frames, the problem of lens edge aberration was not paid attention to. It wasn't until large frames became popular that the problem became apparent. For the spherical lenses, aberration cannot be corrected with the combined lens. Only a few variables of the lens can be found to reduce aberration and improve clarity. Aspheric lenses are designed to reduce the aberration of optical correction lenses and to make lenses flatter and reduce lens magnification. We can get clearer, thinner, lighter-quality lenses. Thus, aspheric lenses are used to reduce aberration and astigmatism to a minimum, close to the natural vision of the naked eye. The spherical aberration can be reduced by changing the curvature of the edge. The refraction in the central region is high and decreases evenly toward the edges.
How to choose frames?
You can choose a thicker frame with the lens, and then pay attention to the temple. It is better to have a little weight, or the frame is easy to lose forward. The shape of the frame can be elliptical. If the frame is rectangular, the rim of the lens may be a little thick. Choose frame TR90 plate and the frame will be wider than ordinary alloy. Of course, if you like metal, there are now metal frames with thick frames.
TR90 glasses frame
TR90 is not easy to deform and break, and it can withstand high temperatures and strong impacts. In addition, its material is relatively light, so many young people also like such glasses frames.