摘要 |
According to an embodiment, a liquid crystal lens device includes an optical element and a voltage controller. The optical element includes: a refractive index modulation layer of which a refractive index distribution changes according to a voltage applied thereto; and electrodes to apply a voltage to the refractive index modulation layer. In a first voltage state, the voltage controller controls voltages applied to the electrodes such that a first refractive index distribution is arranged periodically in the optical element. In a second voltage state, the voltage controller controls voltages applied to the electrodes such that a second refractive index distribution is achieved. In an intermediate voltage state, the voltage controller controls a voltage applied to a first-type electrode, to which a first voltage that is the maximum value among the voltages applied to the electrodes in the first voltage state is applied, to a second voltage lower than the first voltage. |