page_title: Bifocals
hierarchical_section_title: Bifocals
caption_attribution_description: Exhibit in the Franklin Institute, Philadelphia, Pennsylvania, USA.
context_page_description: Bifocals are eyeglasses with lenses that are split between two different strengths. Usually the lower half of each lens is made to help the wearer read, while the upper one is to help the wearer see at a distance.
context_section_description: Bifocals are eyeglasses with lenses that are split between two different strengths. Usually the lower half of each lens is made to help the wearer read, while the upper one is to help the wearer see at a distance.
caption: Bifocals made by Benjamin Franklin
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