Liquid crystal lens unit and 3d display device

The liquid crystal lens unit includes a plurality of the first substrate, disposed on the first substrate, each of which extends in a first direction on the plate surface of the first substrate, each of said first spaced apart in a second direction intersecting the first direction of the lower plate electrode, a second substrate, and a liquid crystal disposed between the upper electrode and the plurality of lower plate electrode layer plate shape of the upper electrode, which is located on the plurality of lower plate electrode formed on the upper electrode It includes, and after sandwiching the at least one lower plate electrode of the plurality of lower plate electrode of the first voltage to each other spaced-apart lower plate electrodes, respectively applied, a lower second voltage is applied to the at least one lower plate electrode compared to the first voltage do.