Progressive lenses are designed to provide distance, intermediate and near vision in one lens.
Unlike a bifocal, there is no visible dividing line. Along the main progression path, additional plus power increases gradually toward the lower part of the lens.
This continuous change in power is the basic structure of a progressive lens.
01 · DISTANCE POWER
The upper area is mainly used for distance vision
In a typical progressive design, the upper area contains the distance prescription for straight-ahead viewing. The exact position and usable width vary by design.
The distance zone is not simply the entire upper half of the lens. Its usable width depends on the prescription, add power, design philosophy and where the lens actually sits in front of the eye. The same design can therefore feel different when frame position and fitting change.
02 · ADDITION
Near addition increases toward the lower part
The ADD value is introduced progressively. If +2.00 D of addition is required, the extra plus does not appear suddenly; it increases continuously along the principal progression path.
Add power is the extra plus needed for near, not a completely separate near prescription floating on its own. It is built on top of the distance prescription as power increases along the progression, so distance power and add must be considered together to understand the total power change.
03 · PROGRESSION
The intermediate zone connects distance and near
As power changes between distance and near, intermediate powers are available for tasks such as computer viewing and indoor distances.
Intermediate vision is not a single fixed point. It occupies part of the continuous power transition between distance and near, so a wearer who works at a computer and a wearer who mainly uses longer indoor distances may prefer different parts of the same lens.
04 · NO VISIBLE LINE
There is no visible boundary between powers
Because surface power changes continuously, there is no segment line like the one seen in traditional bifocals.
Having no visible line means there is no abrupt segment boundary like a bifocal. It does not mean every point on the lens has the same power or clarity; effective power and aberrations continue to change with gaze position.
05 · OPTICAL TRADE-OFF
Continuous power change creates trade-offs elsewhere
The surface geometry that connects distance and near creates unwanted astigmatism and other optical changes around the progression corridor.
Progressive design is therefore about allocating usable distance, intermediate and near zones while managing peripheral aberrations.
That continuous change is both the benefit and the design constraint of a progressive lens. Peripheral unwanted astigmatism and distortion are not automatically manufacturing defects; designers manage where and how strongly they are distributed. A more useful comparison is therefore how the design allocates usable zones and aberrations, not whether aberration exists at all.
SOLUTION GUIDE
Solution guide
Mainly distance vision.
Intermediate distances.
Near vision.
May contain design-related blur and aberration.
GLANOS LENS CHECK
A progressive lens is not a simple three-step lens
Power changes continuously along the progression path, and products differ in how quickly it changes and how the usable zones are arranged.
CAUTION
Not every point in a progressive lens is equally clear for every distance
The viewing distance must match the part of the lens through which the eye is looking.
GLANOS EYEWEAR
There is a reason glasses feel uncomfortable.
progressive lenses · multifocal lenses · add power · intermediate · near · eyeglass lenses