A stripe pattern of known distance is imaged on the ocular fundus by the imaging unit for ophthalmological devices. This makes it possible to carry out absolute measurements of distances and objects at the ocular fundus with knowledge of the initial values serving as a basis. The imaging unit for ophthalmological devices, particularly fundus cameras, according to the invention comprises a device for generating and imaging any, but a known, stripe pattern or line pattern on the retina of an eye to be examined, a camera for recording the stripe pattern or line pattern on the retina, and an evaluating unit for determining the distances on the retina. The imaging unit is constructed in such a way that the stripe pattern or line pattern to be imaged is coupled into the beam path between the ophthalmological device and the eye to be examined. The use of an imaging unit of this kind as an accessory to ophthalmological devices also expands the possibilities for its use in measurements at the ocular fundus. Although the proposed solution is particularly suited to fundus cameras, it can also be used for other ophthalmological device.