Once upon a time, when the optical technology is not so advanced as today, people have the only choice to wear those glass material lenses if they have any vision problem, including myopia and hyperopia. Theses lenses are easy to get fragile and uncomfortable to wear, not to say those strong prescription ones. It was a hard time for people whose Rx was stronger than even -7.00! The glass lenses will be specially thick and heavy, actually, eyeglasses should not be a burden for individuals. Today, our manufactures can provide us the high index plastic lenses, which overcome the drawbacks of the glass materials. People wearing prescription eyeglasses were considered to get back to fashion kingdom again, which nowadays are thought to be a important factor of buying glasses!
These high index lenses have great optical quality and they have a lighter weight compared to the traditional glass material lenses. Actually, when we judge the quality of a lens, two properties are always need to be taken at the first place, the curvature of the lens and the refractive index, the less the curvature is, the thinner the lens will be, while high index lenses have a stronger refractive index, which means they can bend the light more than glass materials, so, the curvature will be low, and the thickness will be thin! The reason why such prescription eyeglasses lenses are lighter is they need fewer materials. High index lenses will be lighter and thinner compared to conventional ones with the same prescription! Actually, the higher the refractive of the material is, the thinner and lighter the lens will be!
So, people even cannot tell a probably prescription of your lens from the appearance of your glasses. We need eye wears not only for function but also fashion, such lenses can be curved and fitted to glasses frames to provide you a trendy look! Additional, you need to order special AR-coatings for your new high-index lenses, as these lenses can not only bend more light, but also block more, so the transmission rate will be lower than ordinary lenses, and your vision will be darker, and other’s cannot see your eyes clearly because of the reflective light glare! But these coatings will improve the rate as much as 98%! However, these prescription eyeglasses lenses are always more expensive, so, I suggest you can buy them at websites, such as prescriptionglassesonline.net, which is really a trustworthy one, you may have a try!
