toric transposition

Toric transposition

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Front and back surface of toric lens

What is a Toric lens? A toric lens is defined as a lens which has one surface toroidal (one of the principal meridians is more curved than the other principal meridian) and another surface of the lens is spherical (convex or concave). What is Toric transposition? It is a method which enables, the Toric lens … Read more

Simple transposition

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It’s a method of converting spectacle prescriptions from one cylinder form to another i.e. plus cylinder to minus cylinder or vice-versa Steps of simple transposition: Step 1: Axis change: If the axis of the cylinder is equal or less than 90 degrees, add 90 degrees If the axis of the cylinder is more than 90 … Read more