Method for generating at least one shear wave in a target region (SP) of a soft solid (S), this method including at least the following steps: a) generating at least one shear wave (SW 1 , SW 2 , SW 3 ) in the target region; b) detecting a propagation pattern (P1, P2, P3) of the at least one shear wave in the target region; c) proceeding to a time reversal of the detected propagation pattern; d) submitting the target region to an excitation set of forces based on the temporally inverted propagation pattern, characterized in that : - step a) is implemented by generating at least two shear waves (SW 1 , SW 2 ) with at least a first source of shear waves (SW 1 , SW' 1 ) and at least a second source of shear waves (SW 2 , SW' 2 ); - step b) is implemented with a detector unit which includes: - a row of ultrasonic transducers (Ti) aligned on a first direction (X10) perpendicular to a detection direction (Di) of each ultrasonic transducer or - a single ultrasonic transducer movable along a first direction (X) perpendicular to its detection direction - during step b), a first propagation pattern (P1) is detected when only the first source is active and a second propagation pattern (P2) is detected when only the second source is active; - during step c), the first and second propagation patterns (P1, P2) are time-reversed independently from each other in order to generate, respectively, a first reverse excitation scheme (P1') and a second reverse excitation scheme (P2'), - at step d), the first source is controlled with the first reverse excitation scheme (P1') to generate at least a first modified shear wave (SW' 1 ), and, simultaneously, the second source is controlled with the second reverse excitation scheme (P2') to generate at least a second modified shear wave (SW' 2 ), whereas the shear waves are focused at a given point (Pi-j) of the target region. a) generating at least one shear wave (SW 1 , SW 2 , SW 3 ) in the target region; b) detecting a propagation pattern (P1, P2, P3) of the at least one shear wave in the target region; c) proceeding to a time reversal of the detected propagation pattern; d) submitting the target region to an excitation set of forces based on the temporally inverted propagation pattern, - step a) is implemented by generating at least two shear waves (SW 1 , SW 2 ) with at least a first source of shear waves (SW 1 , SW' 1 ) and at least a second source of shear waves (SW 2 , SW' 2 ); - step b) is implemented with a detector unit which includes: - a row of ultrasonic transducers (Ti) aligned on a first direction (X10) perpendicular to a detection direction (Di) of each ultrasonic transducer or - a single ultrasonic transducer movable along a first direction (X) perpendicular to its detection direction - a row of ultrasonic transducers (Ti) aligned on a first direction (X10) perpendicular to a detection direction (Di) of each ultrasonic transducer or - a single ultrasonic transducer movable along a first direction (X) perpendicular to its detection direction - during step b), a first propagation pattern (P1) is detected when only the first source is active and a second propagation pattern (P2) is detected when only the second source is active; - during step c), the first and second propagation patterns (P1, P2) are time-reversed independently from each other in order to generate, respectively, a first reverse excitation scheme (P1') and a second reverse excitation scheme (P2'), - at step d), the first source is controlled with the first reverse excitation scheme (P1') to generate at least a first modified shear wave (SW' 1 ), and, simultaneously, the second source is controlled with the second reverse excitation scheme (P2') to generate at least a second modified shear wave (SW' 2 ), whereas the shear waves are focused at a given point (Pi-j) of the target region. <EOS>