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Accommodation Model

Being inherently a thick lens problem, image formation by the eye can be approached using a system matrix. By modeling the fixed portion of the eye with a matrix, assuming the front surface of the crystalline lens to be fixed, then the thickness and back surface power of the lens can be varied to study the accommodation process.

By computing the system matrix for the entire imaging process, constraining the image to fall on the retina, the object distance on which the eye is focused can be calculated. (If an image is to be formed, the object distance must be negative since the Cartesian sign convention is used.) Alternatively, by choosing and object distance, the required back surface power can be calculated.
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