FUNDUS-CAMERA Russian patent published in 1996 - IPC

FIELD: photographic ophthalmologic devices. SUBSTANCE: diaphragm is mounted at focal plane of ophthalmoscopic objective. Illumination channel is provided with assembly of three non-transparent axial screens, one of which is mounted onto the filter cutting away hazardous UV-radiation. Deflecting mirror has coating which transmits IR- and thermal radiation. At photographic and observing channels holder with reproduction lens has two axial holes differing in sizes. Edge of smallest one is brought into coincidence with plane of aperture diaphragm, and edge of the largest hole is sloped to optical axis and has reflecting coating. Sizes of diaphragm, holes of holder, axial non-transparent screens, and properties of filters at illumination channel are related by corresponding equation with angular field, distance from frontal surface (working distance), and with diameter of entrance pupil of fundus-camera, as well as with optical characteristics of ophthalmologic objective and nature of human eyes. Removable prisms-cubes are provided with light- or spectrum- splitting coating at reflecting face. Moreover, prism-cube with light- splitting coating is used together with set of light filters for testing according to fluorescent angiography method. EFFECT: optimization of parameters of optical system; protection of patient's eyes from hazardous affect of radiation; improved reliability of examination. 6 cl, 8 dwg