Patent · US Expired

Complete autorefractor system in an ultra-compact package

US7481535B2 · kind B2 · utility

5Cited by
4References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 22, 2004
Grant dateJan 27, 2009
Priority date
Expiry dateAug 30, 2025

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B3/156
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

An autorefractor system in an ultra-compact package is described for rapidly and objectively measuring the refractive state of the eye. The autorefractor detector system, in conjunction with a secondary light source, uses one photodetector such as a charge coupled device (“CCD”) or one photodiode, to intercept a light beam at two distances from a secondary retinal light source created by one relay lens, one pupil emitter conjugate lens and one pupil detector conjugate lens, as well as a field lens. The signals produced by the photodetector are used to determine the full spherocylindrical refraction of the eye. A novel illumination and imaging system provides multiple capabilities to image the eye, control accommodation, and acquire and maintain optical alignment, while obtaining other measurements of the eye.

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