Eye refractometer
US4293198A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 21, 1978 |
| Grant date | Oct 6, 1981 |
| Priority date | — |
| Expiry date | Sep 21, 1998 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B3/103
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An eye refractometer is provided with a projection optical system for projecting test beams forming test patterns such that the central ray of each test beam passes through the pupil of the eye to be inspected while being spaced apart from the optic axis in order to form test patterns corresponding to three meridians forming 60.degree. with each, a focusing lens disposed in the projection optical system and movable only in one direction during one measurement, and a beam detecting device for detecting the reflected images of the test patterns by the retina of the eye and generating electrical signals corresponding to the three meridians.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.