The mirror group is formed by a monolithic frame bent along a bending line and including a first and a second supporting portions carrying, respectively, a first and a second chips forming two micromirrors made using MEMS technology. The first and second supporting portions are arranged on opposite sides of the bending line of the frame, angularly inclined with respect to each other. The mirror group is obtained by separating a shaped metal tape carrying a plurality of frames, having flexible electric connection elements. After attaching the chips, the frames are precut, bent along the bending line, and separated.