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Equivalent Power
The Equivalent Power is a value that combines the spherical and cylindrical components to provide a concise representation of a lens’s overall power. It is useful for comparing different lenses and for assessing the aesthetic and functional impact of the correction.
What is Equivalent Power?
The Equivalent Power is a measure that allows the power of a lens with a cylindrical component to be expressed in a simplified form. It is obtained by combining the spherical value with half the cylindrical value.
- Formula — Sphere + (Cylinder / 2).
- Synthetic value — It summarises the optical behaviour of the lens.
- Useful for comparisons — It enables you to assess differences between lenses with different geometries or powers.
Why it is important
- Aesthetic assessment — It helps to predict the thickness and shape of the lens.
- Optical design — It supports the selection of materials and geometries.
- Comparison — It makes it easier to compare different optical solutions.
- Assembly — It helps to estimate the final yield in the frame.
Where it is used
At Isolani Optical Centres, the Equivalent Power is used as a technical reference for assessing lenses with complex prescriptions and for optimising the choice of frame and material.
- Lenses with a cylindrical power — The Equivalent Power makes assessment easier.
- Lens geometry — It affects the perception of power.
- Materials — The Equivalent Power helps to estimate the thickness.
- Frame — Form can enhance or amplify perceived power.
Isolani Experience
Each lens is designed with the frame, technical specifications and lifestyle in mind, to ensure an ideal balance between visual quality, comfort and aesthetics.
- 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 Equivalent Power helps to predict how the lens will perform, both aesthetically and functionally, over time. At Isolani Optical Centres, we offer ongoing support through adjustments, non-medical check-ups and updates to your optical solutions where necessary, to ensure your vision remains stable and comfortable.
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The information on this page is provided for information purposes only and relates to the optical and commercial sectors. It does not contain any medical, clinical or diagnostic content.