When choosing a pair of glasses, a number of factors
However, just because these lenses are extremely thin, it does not mean that they are impractical as many very thin lenses are made from polycarbonate, a material that is more than twelve times more shock resistant than the plastic used for normal lenses. Also, many of the thinnest lenses have full UVA and UVB ultraviolet light absorption, protecting the eyes from the harmful effects of the suns rays, as well as anti-scratch and anti-reflective coating, showing that one does not have to compromise on practicality when selecting comfortable and thin lenses.
Ultra-thin lenses are individually crafted to whatever prescription is required and are manufactured with aspheric front and rear surfaces, thereby enhancing optical performance as well as flattening both the front and rear surfaces in order to reduce the lens thickness. Such thin lenses include the 1.76 super flat high index lens, as well as the 1.8 and 1.9 index glass lenses. However, it is recommended that the 1.9 and 1.9 index lenses are only used for very high prescriptions as the weight disadvantage would make this thickness of lens impractical for lower prescriptions, in which case a 1.74 or 1.76 plastic lens would be more appropriate. Also, although the 1.8 index glass lens is the thinnest material used for varifocal lenses, such lenses are around twice the weight of a 1,67 or a 1.74 index plastic lens.
Natalie Eastaugh is the Internet Marketing Specialist for JDRWebsites.co.uk
If you wish to find out more on thinnest lenses as well as information about Glasses Frames and Lenses, go to www.glassesframesandlenses.com