Sensory System


Who invented bifocal lenses?

The original bifocal lens was invented in 1784 by Benjamin Franklin (1706–1790). At that time, the two lenses were joined in a metallic frame. In 1909 J. L. Borsch welded the two lenses together. One-part bifocal lenses were developed in 1910 by researches at the Carl Zeiss Company.


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