The invention relates to a method and a device for the contact-free
determination of the mechanical rigidity of hard, as well as soft
biological materials (e.g. articular cartilage) in body cavities (e.g.
arthroscopically), using a defined jet of liquid. The distance between the
measurement device and the measurement surface (e.g. articulation surface)
is continuously measured in a predetermined measurement zone by means of
an optical method. The inventive solution is suited for measuring the
mechanical rigidity of native cartilage, articular cartilage substitute,
cartilage deficiency fillings or of other biological materials, and
therefore for the user-independent and fast analysis of the quality of
regenerated materials as compared to the native starting material.