IMAGE DISPLAY DEVICE

摘要

An objective of the present invention is to provide an image display device whereby, while alleviating increased lens part thickness, it is possible to switch disparity numbers or viewing angles. This image display device comprises an optical element, a voltage control unit, and a display unit. The optical element changes refractive index distribution according to an applied voltage. The voltage control unit controls the voltage which is applied to the optical element when a first mode applies such that a first refractive index distribution is obtained wherein the optical element acts as a first Fresnel lens, and controls the voltage which is applied to the optical element when a second mode which differs from the first mode applies such that a second refractive index distribution is obtained wherein the optical element acts as a second Fresnel lens which has a larger difference in level than the first Fresnel lens. The display unit is disposed on the rear face of the optical element and displays an image.