PROGRESSIVE EYEGLASS

摘要

A progressive eyeglass has a far-sight zone with a refractive index adapted for far-sight, a near-sight zone with a refractive index adapted for near-sight and an intermediate zone with a refractive index that increases continuously at least in part along the main viewing line from the refractive index of the far-sight zone to the refractive index of the near-sight zone. This eyeglass is characterized by the fact that the refractive index of the glass material, that changes along the main viewing line at least in the intermediate part, contributes at least in part to increase the refractive index.