The invention relates inter alia to an elastography device having at least one excitation unit (10) for generating mechanical tissue movements in human or animal tissue, and an image-recording device.It is provided according to the invention that the excitation unit (10) has: at least one pressure source (20, 20a), at least one pressure-dependently operating actuator (40, 60, 70, 200) for generating mechanical movements, at least one controllable valve (30, 300, 310, 400) which is arranged between pressure source (20, 20a) and actuator (40, 60, 70, 200) in terms of gas flow and the valve position of which influences the pressure acting on the actuator (40, 60, 70, 200), and a control device (50) which is connected to a control port of the valve (30, 300, 310, 400) and which actuates the valve (30, 300, 310, 400) and defines the valve position thereof and, in order to generate the mechanical tissue movements, varies the valve position, and thus the pressure acting on the actuator (40, 60, 70, 200), over the course of time.
