Mrinal Shenoy

Anteryon BV, produces optical lenses at the wafer scale which have applications in several areas, the predominant one being in mobile phone cameras. The basic components of a wafer lens are a polymer, which satisfies the optical requirements, and a glass substrate on which this is bonded. During the manufacturing process, it is observed that the polymer shrinks due to the polymerisation and as a result the final product will not have the designed shape. We attempt to model this deformation of the lens, using the principles of linear elasticity. We formulate the governing differential equations under a set of assumptions and use a perturbation approach to obtain an analytical formula. This formula gives the deformed lens shape after a certain amount of shrinkage has taken place. This enables Anteryon to get explicit results for the lens shapes. Using this expression, we also tackle the inverse problem which is of higher importance to Anteryon i.e. what should be the mould shape in order to get the target lens shape when a certain amount of shrinkage has taken place. This model is  a considerable improvement on the existing empirical models presently used at Anteryon and can be used by the mould designer to predict the ideal mould shape for a desired lens.