A device of the gyrometer type, for detecting a rotation around a first axis, this device being realized in planar technology from a substrate (2, 50), characterized in that it comprises: a) A first zone, called thick zone, located in the plane of the substrate, having a first thickness and comprising: - at least one mass (3, 3', 31, 32, 33), defining, idle, a plane, merged with the plane of the substrate, containing the first axis, this mass being arranged at a distance from a second axis (Z, H, H') of rotation contained in this plane, this mass being able to be caused to vibrate in this plane, perpendicular to the first axis of rotation, - at least two connecting arms to connect said mass to said second axis of rotation (Z, H, H'), b) means for causing said mass to vibrate in its plane, c) a second zone, of second thickness forming, for at least one of the arms (33, 8, 8', 80, 80', 81, 81'), at least one connection (5, 5', 15, 15', 25, 25') with the substrate for a rotation around said second axis of rotation (Z, H, H'), this second zone having a thickness smaller than or equal to that of the first zone, d) a third zone, called thin zone, with a thickness smaller than that of the second zone, forming at least one strain gauge of the suspended type, for detecting the rotational movement around said second axis of rotation, this third zone: - extending in a plane parallel to the plane of the substrate and not containing the axis of rotation, - extending in a plane perpendicular to the second axis of rotation, - being connected, on one hand, to one of the first and second zones and, on the other hand, to the substrate, the thicknesses of the different zones being measured perpendicularly to the plane of the substrate. a) A first zone, called thick zone, located in the plane of the substrate, having a first thickness and comprising: - at least one mass (3, 3', 31, 32, 33), defining, idle, a plane, merged with the plane of the substrate, containing the first axis, this mass being arranged at a distance from a second axis (Z, H, H') of rotation contained in this plane, this mass being able to be caused to vibrate in this plane, perpendicular to the first axis of rotation, - at least two connecting arms to connect said mass to said second axis of rotation (Z, H, H'), - at least one mass (3, 3', 31, 32, 33), defining, idle, a plane, merged with the plane of the substrate, containing the first axis, this mass being arranged at a distance from a second axis (Z, H, H') of rotation contained in this plane, this mass being able to be caused to vibrate in this plane, perpendicular to the first axis of rotation, - at least two connecting arms to connect said mass to said second axis of rotation (Z, H, H'), b) means for causing said mass to vibrate in its plane, c) a second zone, of second thickness forming, for at least one of the arms (33, 8, 8', 80, 80', 81, 81'), at least one connection (5, 5', 15, 15', 25, 25') with the substrate for a rotation around said second axis of rotation (Z, H, H'), this second zone having a thickness smaller than or equal to that of the first zone, d) a third zone, called thin zone, with a thickness smaller than that of the second zone, forming at least one strain gauge of the suspended type, for detecting the rotational movement around said second axis of rotation, this third zone: - extending in a plane parallel to the plane of the substrate and not containing the axis of rotation, - extending in a plane perpendicular to the second axis of rotation, - being connected, on one hand, to one of the first and second zones and, on the other hand, to the substrate, the thicknesses of the different zones being measured perpendicularly to the plane of the substrate. - extending in a plane parallel to the plane of the substrate and not containing the axis of rotation, - extending in a plane perpendicular to the second axis of rotation, - being connected, on one hand, to one of the first and second zones and, on the other hand, to the substrate, the thicknesses of the different zones being measured perpendicularly to the plane of the substrate.