Patent · US Expired

Portable, public use reading glasses eye tester

US5486879A · kind A · utility

5Cited by
2References
5Claims
0Family size

Inventor

Key dates

Filing dateJun 6, 1994
Grant dateJan 23, 1996
Priority date
Expiry dateJun 6, 2014

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B3/032
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

Two identical plates somewhat in the shape of very large eyeglass frames sandwiching two rotable discs, one for each eye, form the front section of the device. Each disc has a series of magnifying lenses of increasing power which can be brought into the eye openings in the plate when the discs are rotated and allow the user to focus on a group of alphbetical characters of a predetermined size and at a predetermined distance from the lenses at the end of a view tunnel. The strength of the lenses required for focusing can then be read from the disc where it is clearly indicated next to each lens. These lens strengths correspond to the power of reading glasses sold non-prescription in most drug stores.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.