The present invention relates to an image display apparatus capable of switching directional display/non-directional display mode which has an image forming part and an optical member for switching the display mode. The optical component includes: two light-transmitting plate members; at least one lens member disposed between the two plate members, the lens member having a predetermined refractive index; a refractive-index variable medium sealed in a gap between the lens member and the two plate members; and a refractive-index adjusting unit that adjusts a refractive index of the refractive-index variable medium, the optical member to be in a first usage state in which the optical member performs a lens action, the optical member is set in a second usage state in which the optical member functions as a light-transmitting plate performing no lens action so that the display mode of the image display apparatus is set to be the directional image display and non-directional display mode.