1. An opthalmological measuring device for determining geometric structures of an eye, comprising an optical, triangulating first measurement system and an optical, interferometric second measurement system, wherein the first measurement system is configured to determine at least one geometric reference in the eye by triangulation and includes a light projector for projecting a light slit and a first scan module for moving the light slit to different positions of the eye, the second measurement system is configured to determine geometric detailed structures in the eye by optical interferometry, and includes an interferometer and a second scan module, with the second scan module being designed to project at least one light beam from the interferometer onto and into the eye at a plurality of different positions of the eye and to supply light reflected by the eye to the interferometer, where the light slit projected by the light projector and the light beam from the interferometer have different wavelengths, and the measuring device is configured to position the geometric detailed structures determined by the second measurement system on the basis of the at least one geometric reference in the eye determined by the first measurement system.