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CE BIO Predict/Explain Treating Cataracts When the lens in a person’s eye becomes clouded by a cataract, the lens can be removed with a process called phacoemulsification and replaced with a man-made intraocular lens The intraocular lens restores clear vision, but its focal length cannot be changed to allow the user to focus at different distances. In most cases the intraocular lens is adjusted for viewing of distant objects and corrective glasses are worn when viewing nearby objects, (a) Should the refractive power of the corrective glasses be positive or negative? (b) Choose the best explanation from among the following
- I. The refractive power should be positive—converging—because the intraocular lens will make the person farsighted.
- II. A negative refractive power is required to bring the local point of the intraocular lens in from infinity to a finite value.
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