Single Vision vs. Progressive Lenses: How Modern Freeform Technology Works

Around the age of 40 to 45, you may notice having to hold menus or smartphones further away to read clearly. This condition is known as presbyopia.

Presbyopia is not a disease; it is the natural hardening of the crystalline lens inside the eye, making it harder for the ciliary muscles to flex for close-up tasks.

Traditional bifocals split the lens into two distinct zones with a visible dividing line. This created an abrupt "image jump" and provided zero clarity for intermediate computer distances (60cm–1m).

Progressive addition lenses (PALs) incorporate an invisible vertical corridor with gradually increasing optical power. You look straight ahead for driving, slightly down for desktop computers and lower down for reading phone text.

Older generation progressives caused a noticeable "swim" sensation when turning your head quickly due to peripheral aberration.

At St. Mary Optical, we fit digital freeform back-surface progressives. These are custom cut with point-by-point laser precision, widening your reading field by up to 40% and making adaptation seamless within 24 to 48 hours.