Addition

What is Addition?

The Addition expresses the additional power required to focus on objects at close range. It is a key parameter in the design of progressive and bifocal lenses.

• Value expressed in dioptres — Indicates the additional power for the neighbour.
• It stems from the difference between far and near — It is not an independent power.
• Available only in multifocal lenses — It does not appear in single-vision lenses.

Why it is important

• Comfort when reading up close — It allows for natural focusing at close range.
• Smooth transition — In progressive lenses, it determines the quality of the transition between distance, intermediate and near vision.
• Accuracy — An appropriate setting improves stability and sharpness.
• Optical design — It affects the geometry and distribution of the visual zones.

Factors influencing the Addition

At Isolani Optical Centres, the selection of the Addition is based on visual needs, lifestyle and technical specifications, to ensure natural and comfortable vision.

• Progressive lenses — The Addition determines the structure of the visual zones.
• Lens geometry — It affects the distribution of power.
• Frame — The shape must support the correct positioning of the visual zones.
• Centring — Essential for a smooth transition between distances.

Isolani Experience

Each multifocal lens is designed with the frame, technical specifications and lifestyle in mind, to ensure an ideal balance between visual quality, comfort and a natural transition between distances.

• Bespoke glasses — Complete customisation of the frame and choice of lenses.
• Behavioural Centring — Real-world operating parameters for precise design.
• Simulation Room — Aesthetic and functional checks prior to production.

Ongoing support

The Addition affects the naturalness of near vision and the smoothness of transitions. At Isolani Optical Centres, we offer ongoing support with adjustments, non-medical check-ups and updates to your optical solutions whenever necessary, to ensure your vision remains comfortable over time.

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