Alcon, Inc.

Marcus Heift

Susanne Fechner

Roger Biel

Matthias Schwab

Thomas Tonn

Sarah Unterkofler

A method for determining the inversion state of a soft contact lens (), comprising imaging a soft contact lens having a convex surface () and a concave surface (), a lens center and a lens edge () surrounding said soft contact lens (), the method comprising using an optical coherence tomography system to obtain at least one sectional image of at least a part of the contact lens () comprising the lens edge (), determining a cross-sectional edge geometry of the contact lens () extending from the lens edge () towards the lens center of the contact lens in the sectional image, the cross-sectional edge geometry corresponding to the convex and concave surface boundaries of the contact lens () in the sectional image, selecting a parameter defining the cross-sectional edge geometry of the contact lens () imaged and comparing the parameter defining the cross-sectional edge geometry of the contact lens () with a predetermined parameter defining a cross-sectional edge geometry of a non-inverted contact lens to determine whether said contact lens () is inverted.

Contact lens inspection method and system

Method for determining the refractive index (n) of a material of a contact lens, in particular of a soft contact lens, the contact lens () having a first surface and a second surface defining a lens geometry there between, by measuring the wavefront issued by the contact lens () with a wavefront sensor (), obtaining data of the geometry of at least one section of the contact lens () with an optical coherence tomography system () and communicating the geometry of the at least one section of the contact lens () from the optical coherence tomography system () to an analyzer, particularly a computer, and determining the refractive index (n) of the material of the contact lens from the geometry of the at least one section of the contact lens and from the wavefront issued by the contact lens ().

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Aschaffenburg, Germany

Marcus Heift