1 янв 1824 г. - biofocals

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that split bifocal lenses had a famous gentleman inventor. Since many inventions are developed independently by more than one person, it is possible that the invention of bifocals may have been such a case. John Isaac Hawkins, the inventor of trifocal lenses, coined the term bifocals in 1824 and credited Dr. Franklin.


John Isaac Hawkins invented trifocals, glasses meant to focus on three different distances, in 1824. Though he gave the glasses their name, he credited Benjamin Franklin for inventing the bifocals.

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