Imaging optical system for use with e.g. keratometer, has shielding element inhibiting direct irradiation of light emitting from light radiation surface into light entry surface, where radiation surface is designed as circular ring

摘要

The system has a lighting device lighting an object (7) that is to be represented. A light entry surface (8) for an illumination light (6) is reflected, strewn or converted into luminescence by the object. The lighting device has a light source i.e. organic LED (4), with a light radiation surface (5) that emits visible UV or infrared radiation with homogeneous or constantly varying brightness. A shielding element inhibits direct irradiation of the light emitting from the light radiation surface into the light entry surface. The radiation surface is designed as a circular ring.