A scanning device includes a substrate, which is etched to define a recess in the substrate and to define the following structures contained in the recess: At least first and second mirrors are disposed along a common axis of rotation. Torsion hinges extend collinearly along the axis of rotation and connect the first and second mirrors to the substrate so that the first and second mirrors rotate on the torsion hinges about the axis of rotation. Rigid struts are disposed alongside the axis of rotation and connect the first mirror to the second mirror so that the struts rotate about the axis of rotation together with the first and second mirrors.