Progressive (varifocal) lenses are designed for people from around age 45, when presbyopia sets in and the eye can no longer switch flexibly between near and far. Instead of two pairs of glasses, one progressive lens covers the whole range: the upper part is set for distance, the lower for a reading distance of about 30–40 cm, and the progression channel in the middle provides the intermediate values – ideal for a screen.
For this to work, the glasses must be fitted precisely to the face and habits. Besides the prescription, the optician measures pupillary distance, fitting height, pantoscopic tilt and vertex distance. The more accurate this centring, the larger the usable sharp zones and the smaller the peripheral blur areas that every progressive lens physically produces. Higher-grade lenses (individually optimised, freeform) have wider corridors and are easier to wear.
Getting used to them usually takes a few days to two weeks. At first you may need to move your head rather than just your eyes, as you learn to look through the correct zone. People who work a lot at a computer sometimes do better with an additional screen or room lens (office lens).
In Switzerland a complete pair of progressive glasses costs roughly CHF 600 to 1,500 depending on lens quality, coatings and frame, with premium freeform lenses higher (guide values, no guarantee). The lenses make up the largest share; anti-reflective coating, blue-light filter or self-tinting lenses come at extra cost. For adults, basic health insurance normally pays nothing towards glasses.