When you order eyeglass lenses, you might come across the term “edge” in your prescription or during the lens selection process. What does “edge” mean in the world of eyeglasses, and why is it important? Let’s explore this concept.
What Does “Edge” Mean on Lenses?
In the context of eyeglasses, “edge” usually refers to the outermost part of the lens, specifically the lens’s thickness at its outer rim. Lens thickness varies across the lens, with the center being the thinnest and the edges being thicker. This thickness at the lens periphery is often a concern for those with higher prescriptions.
Why Does Thickness Matter?
Thickness matters primarily for aesthetic and cosmetic reasons. Thicker edges can create a bulging or unattractive appearance in eyeglasses, especially for people with strong prescriptions. It can also affect the overall weight of the glasses and how they fit on your face.
Lens Edging and Reducing Edge Thickness:
Lens edging is the process of shaping and finishing the lens to fit it into the frame correctly. During this process, the optician or lab technician pays special attention to the lens’s thickness. They can employ several techniques to minimize thickness:
- High-Index Lenses: High-index lenses are a type of lens material that is thinner than standard materials for the same prescription. They are particularly beneficial for individuals with high prescriptions as they reduce thickness.
- Aspheric Lenses: Aspheric lenses have a more gradual curvature across the surface, reducing thickness and distortion, especially at the edges.
- Lens Material: Choosing a lens material with a higher refractive index can significantly reduce thickness while maintaining clarity.
- Proper Frame Selection: Certain frame styles, such as full-rim or semi-rimless, can help conceal thicker edges or make them less noticeable.
- Frame Size and Shape: Smaller frames and frames with rounded or oval shapes tend to hide thickness better than larger, rectangular frames.
Consulting Your Optician:
If you’re concerned about thickness and its impact on the appearance and comfort of your glasses, it’s essential to discuss this with your optician or eyewear professional. They can recommend suitable lens materials, frame styles, and lens design options to address your specific needs.
In conclusion, “edge” in the context of eyeglass lenses refers to the thickness of the lens at its outer rim. While the thickness can affect the aesthetics of your glasses, modern lens materials and edging techniques offer solutions to reduce this thickness and provide you with comfortable, attractive eyewear tailored to your prescription and style preferences.