A pair of eyeglasses is normally consisted of two lenses and a frame. Rimless eyeglasses still have two temples and a bridge used to connect the lenses. It is commonly known that eyeglass lenses are the critical section for the wearers to get normal vision. From a brief perspective, eyeglass lenses have prescription ones and non-prescription ones. While the first category is the majority in the market, the latter one is still popularly used. Non-prescription eyeglass lenses are sometimes called plain lenses, meaning they are not for vision correction. Dissimilar to prescription eyeglass lenses either concave or convex, non-prescription lenses are plain. These plain-surfaced eyeglasses lenses are used simply for fashion or eye protection. Utilizing plain lenses, there are regular sunglasses and protective goggles. These plain eyeglass lenses have long been existent for many years and will continue to stay in the market.

The other main category is prescription eyeglasses used for vision correction. They can either be convex or concave. The former type is capable of correcting hyperopia and the latter type is for myopia. These two types of non-plain eyeglass lenses help the nearsighted or farsighted eyes focus light entering the eyes properly. Even if there are popular contact lenses and eye surgical treatments, prescription eyeglasses have remained as an indispensable solution for many individuals. Using prescription eyeglass lenses is actually the simplest method. Compared with plain lenses, convex or concave eyeglass lenses are more complex and expensive.

Within the prescription lenses, there are still sub-categories, including single vision lenses and multifocal lenses. Suggested by the name, single vision eyeglasses are able to deal with only one vision problem. Regular prescription eyeglasses fall into this category. Until now, single vision spectacles have been the major role in the market. Individuals with nearsightedness or farsightedness are main participants of those single vision glasses. In addition, there are still multifocal eyeglass lenses, containing bifocals, trifocals and progressive ones. These eyeglass lenses are mainly for folks with presbyopia, who are still suffered by nearsightedness. It is easy to understand that multifocal eyeglass lenses can resolve more than one vision problem at the same time.

In fact, there are still many other aspects of eyeglass lenses, in addition to lens power or powers. Lenses for fashion can be applied with different colors. For extra lens feature or property, there are available various coatings. From a basic viewing point, eyeglass lenses can be made from glass or plastics.

In the modern eyewear market, there are numerous options of eyeglass frames and lenses. General types include plastic frames, plastic lenses, metal frames, and glass lenses and so on. In addition, all these basic types can then generate a lot more combinations. So eyeglass customers living in the modern society are really lucky. It is worth noting that all of these eyeglass categories are not directly associated with their functionality. According to the latter aspect, eyeglasses have types such as prescription glasses, sunglasses and protective goggles. Thanks to technologically improvement, neither functional glasses nor accessory eyeglasses are limited by certain lens or frame materials. In the long history of eyeglass progression, the application of plastics as lens and frame materials has been a significant event. Before this breakthrough, nearly all eyeglass lenses were composed of glass and most eyewear frames were limited to metal ones. The invention of plastic frame eyeglasses and plastic lens eyeglasses was really a valuable gift for eyeglass users.

Plastic eyeglass lenses have been widely praised by the public due to their particular benefits. These lenses are considerately lighter and more durable than traditional glass lenses. In the recently years, many more forms of plastics are even becoming more popular. These advanced plastics include CR-39, polycarbonate, and high index plastics and so on. Plastic eyeglass lenses really deserve all of the applause. On the other hand, eyeglass frames have also benefited significantly from plastics. Plastic frame eyeglasses have long been a good alternative to those metal frames. Being the two basic types, both plastic frame eyeglasses and metal frame ones have respective advantages. This article focuses on advantages of the first category over the latter one.

The first advantage of plastic frame eyeglasses compared with metal ones is lightness. This is probably the most obvious difference between the two frame types. It is true that some forms of metal are also lightweight. For instance, titanium as a superior frame material is lightweight, durable as well as strong. But in general, metal frames are heavier than plastic ones. Plastic frame eyeglasses also feature durability, so that they do not bend easily. Metal frames are easier to lose the original shape. But one disadvantage associated with durability is that plastic frames are more likely to melt under a high temperature. A third advantage of plastic frame eyeglasses is the options of color. Most wearers can enjoy more color options from choosing plastic frames. It is also necessary to balance those benefits of plastic frame eyeglasses against their disadvantages.

In the modern eyewear market, there are numerous options of eyeglass frames and lenses. General types include plastic frames, plastic lenses, metal frames, and glass lenses and so on. In addition, all these basic types can then generate a lot more combinations. So eyeglass customers living in the modern society are really lucky. It is worth noting that all of these eyeglass categories are not directly associated with their functionality. According to the latter aspect, eyeglasses have types such as prescription glasses, sunglasses and protective goggles. Thanks to technologically improvement, neither functional glasses nor accessory eyeglasses are limited by certain lens or frame materials. In the long history of eyeglass progression, the application of plastics as lens and frame materials has been a significant event. Before this breakthrough, nearly all eyeglass lenses were composed of glass and most eyewear frames were limited to metal ones. The invention of plastic frame eyeglasses and plastic lens eyeglasses was really a valuable gift for eyeglass users.

Plastic eyeglass lenses have been widely praised by the public due to their particular benefits. These lenses are considerately lighter and more durable than traditional glass lenses. In the recently years, many more forms of plastics are even becoming more popular. These advanced plastics include CR-39, polycarbonate, and high index plastics and so on. Plastic eyeglass lenses really deserve all of the applause. On the other hand, eyeglass frames have also benefited significantly from plastics. Plastic frame eyeglasses have long been a good alternative to those metal frames. Being the two basic types, both plastic frame eyeglasses and metal frame ones have respective advantages. This article focuses on advantages of the first category over the latter one.

The first advantage of plastic frame eyeglasses compared with metal ones is lightness. This is probably the most obvious difference between the two frame types. It is true that some forms of metal are also lightweight. For instance, titanium as a superior frame material is lightweight, durable as well as strong. But in general, metal frames are heavier than plastic ones. Plastic frame eyeglasses also feature durability, so that they do not bend easily. Metal frames are easier to lose the original shape. But one disadvantage associated with durability is that plastic frames are more likely to melt under a high temperature. A third advantage of plastic frame eyeglasses is the options of color. Most wearers can enjoy more color options from choosing plastic frames. It is also necessary to balance those benefits of plastic frame eyeglasses against their disadvantages.