Providing an electrostatic machine element for restraining deteriorations of practical electrostatic forces between electrodes by an electrostatic shielded effect to prevent instability of an electrode operation, a light diffraction modulation element using the electrostatic machine element and an image display device using the light diffraction modulation element. An edge and an upper side of a first electrode are opened and a dielectric material, the mobility of which depends on a polarity of an electric charge, is used for a second dielectric film. When a drive voltage such that the electric charge having high mobility moves from one dielectric film to another dielectric film, is applied between the first electrode and a second electrode, a charged particle that arrived at the first dielectric film moves further to the upper side of the first electrode.