# trifocal lenses

> eyeglass lens with three distinct optical powers

**Wikidata**: [Q7841511](https://www.wikidata.org/wiki/Q7841511)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Trifocal_lenses)  
**Source**: https://4ort.xyz/entity/trifocal-lenses


## References

1. [Source](https://books.google.com/books?id=9I3oH--MnVYC&lpg=PA205&dq=john%20hawkins%20ben%20franklin%20lenses&pg=PA205#v=onepage&q&f=false)