The diagnosis of hemodynamics of microvessels may affect the early detection of the consequences of metabolic disorders such as diabetes or affections of the whole vascular system such as hypertension. In particular, the eye presents a showcase of microvascular network accessible to optical imaging methods. Complications of diabetes or hypertension can lead to microvascular remodeling which can manifest by occlusion or dilation of veins and capillaries and neoangiogenesis, and can cause partial or total blindness. It is estimated that 40% of diabetics are holders of retinopathy (more than one million people in France). Beyond the potential in medical imaging, mapping quantitatively microvascularisation presents a scientific interest. Many models of stroke, neurovascular coupling, or neoangiogenesis in the small animal could be judged in quantitative and reproducible manner. For these medical and biological challenges, no comprehensive method of blood microflow mapping in broad ranges of flow speed is available. We propose to develop robust biorheological Doppler imaging methods applied to the quantitative measurement of blood microflow, in vivo, in non-invasive conditions. This project takes place in an international context in which the imagery of the microcirculation throughout a whole system (the microvascular network of a tissue) is based on non quantitative and not reproducible methods. Currently, the most common medical assessment of the microcirculation in tissue is the assessment by direct imaging in white light or by an invasive method: the fluorescein angiography. The diagnostic by Doppler acoustic imaging schemes are rarely used because their speed resolution are not appropriate for microflow diagnosis. In practice, two instruments will be developed : an imaging method based on already validated Doppler interferometry with a laser source of long coherence length and an imager based on low temporal coherence interferometry. The first one will allow imaging of superficial vasculature and will mainly be used for experiments on the retina. The second one (based on low coherence interferometry) will be used for scattering tissue exploration in depth (about 1 mm) and will allow Doppler optical coherence tomography, with a resolution of the order of ten microns (the size of a typical cell).