Provided is a small size, high resolution display element with an extremely high utilization efficiency of light emitted by a light source unit and a high contrast. A display element of the present invention has a photonic crystal, a light source unit, and a control unit. The control unit changes the resonance wavelength of point defect resonators formed within the photonic crystal, thus effecting a control between a state in which light guided from the light source unit to a linear defect waveguide is emitted to the outside of the photonic crystal, and a state where emission of light to the outside of the photonic crystal is blocked.