But, you ask, won't that be difficult when Glass is outfitted with prescription lenses one day?

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You can swap out the removable sunglass lenses for clear versions, or throw in your prescription in daylight (tinted) or indoor flavors, since many optical stores stock appropriately sized lenses.

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Del Vecchio isn't banking just on prescription glasses, not with so many people opting for contact lenses or corrective surgery.

FORBES: Lens master

Del Vecchio isn't just banking on prescription glasses, not with so many folks opting for contact lenses and corrective surgery.

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In most states contact lenses can be sold only with proof of a valid prescription--either a written prescription or oral approval from an ophthalmologist or an optometrist, who make their livings largely from the stuff they sell, contact lenses among them.

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