John Isaac Hawkins, the inventor of trifocal lenses, coined the term bifocals in 1824 and credited Dr. Franklin.
Trifocals were invented by Benjamin Franklin in the 18th century. He created these lenses by cutting different sections of lenses and combining them into one, allowing wearers to see clearly at varying distances.
bifocals in 1884, but trifocals were in the 40's1 year ago
Varifocals
Trifocals are not popular in UK because people are using progressives lenses. I am wearing trifocal since I am 50 years old and my vision is quite better compare to when I was wearing progressives lenses. Tim.
jv
Gloria Mejia invented it and she invented it in 1998
invented in 500BC before electricity was invented
The CD was invented in 2001 Thomas clamps invented it.
When and where were snickerdoodles invented Why were snickerdoodles invented
who invented the washboard?
Yes, the computer is invented.
Invented is the past participle of the verb invent. verb /past /past participle = invent /invented /invented