There is provided a scanning mirror device with a microsystem scanning mirror which is mounted rotatably about at least one axis, and a detection module which has a light source which emits a light beam, and a position detector, wherein the detection module directs the light beam onto the scanning mirror from behind, with the result that the light beam is reflected, at the back of the scanning mirror, to the position detector which measures the position of the reflected light beam, from which the rotation angle of the scanning mirror about the at least one axis can be deduced.