Apparatus and method for measuring vision defects of a human eye
US6270221A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 2000 |
| Grant date | Aug 7, 2001 |
| Priority date | — |
| Expiry date | Sep 20, 2020 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B3/1015
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Optical characteristics of optical systems, such as the eye, are measured including vision defects of the eye using a collimated beam from a diode laser focused onto the anterior surface of the cornea of the eye for providing a finite source of secondary radiation on the retina of the eye, the image of which is close to a desired diffraction limited spot. The secondary radiation is reflected back from the retina as a reflected wavefront of radiation that passes through the eye and is directed onto a wavefront analyzer where distortions associated with the reflected wavefront are measured. By focusing on the cornea through a long focal length lens and thus converging the beam through a small angle, as opposed to typically focusing a collimated light onto the retina, the need for lenses or lens combinations, and the time required to adjust such to accommodate the differing vision of each patient is eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.