ArticleVilser W, Königsdörffer E, Brandt HP, Jütte A, Dietze U, Deufrains A, Wittwer B.
Albrecht Von Graefes Arch Klin Exp Ophthalmol. 1979;212(2):109-15.
An additional unit which can be used for length measurements at the fundus of the human eye is described for the ophthalmoscope. The principle of measurement is based on optical displacement of the measuring object to itself. The optical displacement of picture points is made possible by the use of a tilting flat glass plate in the intermediate image plane of the eyepiece. The relation between the optical displacement of picture points and the measuring movement is sufficiently linear for the described device.