Semi-finished 1.56 Flat Top UC/HC/HMC Bifocal Lens

● Lenses with a higher refractive index (like 1.61 or 1.67) are thinner, but they can be more expensive. 1.56 is often seen as an ideal middle ground for people who want both performance and affordability.

● Semi-finished lenses are produced with a general curvature and size, but they are not fully shaped or cut to the final prescription. This allows for flexibility in customization for individual prescriptions.

● Flat top means the lens design has a flat-top bifocal (a segmented design where the top portion is for distance vision and the bottom for near vision, like reading). This is helpful for people with presbyopia, which is a condition where near vision deteriorates with age.

● Compared to glass lenses, 1.56 lenses are much lighter while still providing a decent amount of strength and clarity. This is particularly useful for individuals with stronger prescriptions, as they will experience less lens weight, making the glasses more comfortable to wear.