Round-Top (C-Seg) Bifocal Lenses

Product Introduction

Aesthetic Bifocal Design: The Round-Top Optical Profile

Round-top bifocals, frequently identified as C-Seg lenses, represent a more classic and aesthetically softened approach to multi-focal correction. Unlike the sharp horizontal edge of the flat-top, the round-top segment features a curved upper boundary that blends more naturally into the lower half of the lens. From an engineering perspective, the round segment is cast with a specific focus on peripheral softness, which can be beneficial for certain types of close-up tasks. These lenses were historically the standard for bifocal wearers and continue to be popular for specific vocational uses or for patients who have become accustomed to the "round" visual scanning pattern. The near-vision segment is typically 22mm or 28mm in diameter, providing a concentrated area of magnification that is ideal for reading and detailed handheld work. Our production process utilizes ultra-clean molds to ensure that the boundary of the round segment is crisp and free from optical aberrations. This design is particularly well-suited for smaller frames where a flat-top segment might appear too bulky or intrusive. While progressive lenses have gained market share, the round-top bifocal remains a vital tool for practitioners who need to provide a stable, high-contrast near-vision zone with a classic look and feel. The lens is compatible with all modern coatings, including hydrophobic and blue-light filters, ensuring that traditional design meets modern protection.