Fundus camera accessory for analysis of the ocular fundus contour

摘要

An accessory is provided to enable the use of a fundus camera in the photogrammetric analysis of the ocular fundus contour. The accessory includes a stripe projector which projects an image of a grating such that the grating appears to be at infinity. This is accomplished by placing the grating at about the rear focal plane of the projection lens system. A mirror reflects the projected stripes into the eye along a projection axis parallel to the camera optic axis. The mirror also serves as an aperture stop near the eye so that the grating is clearly imaged at all depths of the optic disc cup. A predetermined relationship between the projection optic axis and fundus camera optic axis is maintained by supporting the projector from the front lens housing of the fundus camera. To that end, a sleeve fixed to the projector fits closely around the lens housing. The light source may be one of coherent or incoherent light.