Automatic eye-refractometer
US4372655A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1979 |
| Grant date | Feb 8, 1983 |
| Priority date | — |
| Expiry date | Sep 13, 1999 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2562/043
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An automatic eye-refractometer includes a projector for projecting a test pattern onto the fundus of an eye to be examined, a photo-electric device disposed to receive an image of the test pattern reflected upon the fundus of the eye, a calculator for calculating the refractive power of the eye using outputs from the photo-electric device and a processor for processing the results of the calculation into digital video signals. The eye-refractometer is further provided with a video camera for image picking up the front part of the eye through an objective lens of the projector to produce video signals and a video display device for displaying on a screen a picture produced from the video signals. With the measuring apparatus, the examiner can observe the image of the front part of the eye to be examined and can properly arrange the eye and the objective lens to each other while watching the picture displayed on the screen. By putting the digital signals into the video display device from the processor there are also displayed on the screen numerals, characters or other symbols informing of the refractive power of the examined eye.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.