High Index Lenses in Rimless Frames
The advent of high index lenses allows for greater flexibility in frame selection, especially in the case of strong prescriptions. The nature of high index glass or plastic allows for the use of less material than standard glass or plastic lenses – a particular benefit for stronger prescriptions, since high index materials can form these prescriptions in a thinner, lighter format.
Rimless Frames and High Index Lenses
This reduction in thickness and weight has several advantages. One of them is that many strong prescriptions can now be ordered to fit rimless frames. Previously, the design of rimless frames proved too fragile to accommodate thick, heavy lenses. Also, consumers of stronger prescriptions were often discouraged from using the rimless style by the fact that rimless lenses are partially or completely exposed. Stronger prescriptions require additional thickness around the edges; these thicker edges can be masked within a full-frame format but are not as visually appealing in a rimless style. With high index lenses, however, greater numbers of corrective eye-wear wearers can opt for frame designs of their choice, including frameless rims.
Rimless eyeglass frames are popular because they suspend lenses in front of your eyes without the extra bulk of a supporting frame. Two different styles are considered rimless: three-piece glasses, in which “naked” lenses are connected and suspended with a nose bridge and temple arms, and rimways, which add an arch at the top of the lenses for additional support. With the rimway style, the sides and bottom of the lenses remain exposed. Several framewear variations of rimless glasses have evolved over the years, and regardless of eye-wear trends for any given period, it’s not uncommon for at least some of these variations to remain in vogue.
Bear in mind that the availability of rimless frames is limited to high index plastic. High index glass lenses are even heavier that standard glass lenses and rimless frames cannot support them. If your prescription is extreme enough, high index lenses may only be available to you in glass…thus not in a rimless format.
If you favor a rimless style and you wear a prescription that leans towards the high side, you may want to consider using high index lenses. You may find that rimless styles that previously were not available to you can be ordered with high index lenses.