Optical system for illuminated viewing instruments
US4526449A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1982 |
| Grant date | Jul 2, 1985 |
| Priority date | — |
| Expiry date | Aug 16, 2002 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B3/1208
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An optical system for illuminated viewing instruments comprising a light source lamp having an arcuate filament and a coacting mirror having an arcuate viewing passage in its upper edge. The optics of the system operate to focus the image of the filament on the mirror in concentric relation to the arcuate viewing passage whereby the axis of the reflected filament light and the viewer's line of sight are nearly coincident. In order to have all of the curved filament in focus on the mirror, the filament is tilted or disposed at an oblique angle to the longitudinal axis of the lamp. The optical system of the invention also permits use of a fixation pattern and provides the means for precisely focusing the pattern on the fundus of the patient's eye.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.