Résumé
We present a series of experiments, using different techniques such as light scattering, conoscopy, neutron scattering and microscopic observations, to determine the orientation of lyotropic lamellar phases under shear. Three states of orientation are observed, depending upon both the shear rate and the inter-membrane separation. These steady states are separated by dynamic transitions. Among the states described, we focus our attention on a state made of monodisperse close-packed multilayered vesicles whose size is precisely fixed by the shear rate.