The invention relates to an apparatus and a method for imaging the microstructure of an animal or human lung by way of introducing a fluoric contrast gas into the lung which is to be imaged; definition of the apparent diffusion coefficient of the contrast gas by way of diffusion weighted .sup.19fluorine magnetic resonance tomography and based on the determined apparent diffusion coefficients; and imaging of the lung's microstructure. The current invention also describes a device for the implementation of the inventive method. The science of the current invention allows for the first time the production of a high resolution image of the microstructures of the lung through non-invasive measures, by way of fluorinated gases.