type a configuration of the image forming apparatus using this optical modulator element can be made simple also according to the optical modulator element 100 the light from the light source is passed through the opening portion 6 b in the on state and is emergent onto the image forming plane and therefore the element having a light utilization efficiency of 100 can be accomplished the normal reflection optical modulator element reflects the incident light toward the emergent portion or the light absorbing member by displacing the reflecting mirror provided to the movable portion and thus switches the on state and the off state according to this approach when the reflecting mirror is angled by bringing the movable portion into contact with the substrate a vibration of the reflecting mirror is generated in reaction thus such a problem exists that the on light emitted after the reflection is also vibrated also in the normal transmission optical modulator element design and drive of the movable portion must be adjusted according to the wavelength of light emitted from the light source however according to the optical modulator element 100 the problem such that the on light is vibrated does not occur because the light passes through the opening portion 6 b and design and drive can be carried out irrespective of the wavelength of light emitted from the light source in this case if the reflecting mirror 6 a can block the light that is incident on the opening portion.