Title: Ophthalmoscopic optical system

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Abstract: An opthalmoscopic optical system for photographing the fundus of an eye by an ophthalmoscopic camera, it is necessary to illuminate the ocular fundus through the cornea. On the cornea, however, a part of the illuminating light is reflected with the result of production of halo in an image of the ocular fundus. This can be avoided by separating an illuminating light incident area of the cornea from that serving for the emergence of image forming rays to keep this part free from reflexes. According to the present invention, there is positioned between an objective lens and an image-forming lens aligned on a common optical axis is an inclined illuminating plate is positioned between objective lens and an image-forming lens of such construction that a mirrored central area in the vicinity of the optical axis is surrounded by an annular transparent zone which directs light from an illuminating arrangement to the objective lens to suppress the production of a halo. When the ophthalmoscopic camera is set up at an effective distance from an eye to be examined, as the mirror and the cornea of the eye are conjugate to each other with respect to the objective lens, the illuminating light passes the cornea at a central portion thereof, from an outer annular zone of which emerges light reflected from the ocular fundus.


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