Contact Lens: How to focus light 1mm away

AI Thread Summary
To focus on an object 1mm away, a contact lens must be designed to adjust the eye's focal length, typically around 4 cm. The focal length of the lens is crucial, as the eye's ability to accommodate affects how light is focused. Various optical models, such as Liou and Brennan's, can help determine the necessary lens shape and prescription. Understanding these parameters is essential for creating effective contact lenses for extreme close-up vision. Accurate calculations and models are key to achieving this optical challenge.
clalburn1420
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So, I've been wondering. Anyone know what shape/prescription a contact lens would have to be in order for an eye to be able to focus on something 1mm away (assuming the distance of focus in the eye is around 4 cm)? Does it have to do with focal length of the lens?
 
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Great link. Thanks a lot.
 
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