Best Lens Material to Use for Rimless Eyeglasses
Rimless eyeglasses are a very popular frame style because of their light, airy, “barely there” look.
What is the Best Lens Material for Rimless Eyeglasses?
They do away with the standard frame by either suspending the lenses from an overhead bridge (leaving the sides and bottoms of the lenses exposed), or mounting them directly to the temple arms without use of an overhead bridge. Lacking a bulky, lens-encircling frame, rimless eyeglasses allow visual access to more of the face rather than segregating – and drawing more attention to – framed eyes.
Unfortunately, the lack of a surrounding-mount frame also means a reduction in stability and durability. Since lenses are exposed they are more prone to damage than full-frame styles. Because of this, and because exposed lenses are visible to onlookers, rimless lenses rely heavily on the type of material used to fashion the lenses. Two factors come into play here: stability and thickness.
Stability is linked to the durability and rigidity of the material used to make lenses. Standard plastic and glass lens material is more than adequate when protected inside a full frame, but when the lenses are exposed in a rimless style, standard glass and plastic lack the required impact resistance. In a rimless style they are exponentially more likely to break if dropped, sat on, or involved with any sort of contact. In fact, the basic stress of everyday use in a rimless style is likely to wear down standard lens materials over time, making them more susceptible to breakage and frame separation.
Thickness of the lens is the other factor limiting the use of rimless glasses. Stronger prescriptions require more physical material, producing lenses that are too heavy for the rimless format. Stronger prescriptions can also require too much of a curve, resulting in thick edges that do not look good or simply do not fit in an overhead bridge.
To address the stability issue, lenses should be made of a polycarbonate plastic. Polycarbonate – the same material used to manufacture airplane canopies and bulletproof glass – is highly impact-resistant and rugged enough to withstand the vulnerably of exposure in rimless glasses. It has a higher shock tolerance level and, as an added benefit, is often lighter than standard plastic…which helps with our second issue.
To address the lens thickness issue, those with moderate-to-high strength prescriptions may want to switch to a high index plastic material for their lenses. High index plastic allows prescriptions to be cut using less lens material and with less of a curve, resulting in a reduction of the overall lens thickness. This is especially noticeable at the edges of the lenses and may reduce the edges enough to make them viable in a rimless style. High index materials also weigh less than standard materials. Hence, a strong prescription made of high index plastic may become light enough to fit a rimless selection that otherwise would not be available to you.
If you’re “on the bubble” about rimless glasses, speak to your optometrist about the options or give us a call here at Rx-Safety. It may be possible for you to make use of the benefits of polycarbonate or high index plastic to order that rimless style you’ve always wanted in your next pair of eyeglasses.