To provide a micro mirror device and an array thereof.

An outer frame 52 is formed at a position distanced from a mirror plate 51, thereby reducing a dynamic deformation of the mirror plate 51, preventing degradation of beam reflected from the mirror plate 51, and enabling to maintain the degree of the flatness of the mirror plate 51. Further, a frame structure supporting a diaphragm of the mirror plate 51 is made to be thinner as it is distanced from the central axis of the mirror plate 51, thereby reducing the dynamic deformation of the mirror plate 51 to a great extent and embodying the lightness of an element.