An image display device including an image display panel configured to display a 2D image and a 3D image, a driving circuit configured to apply a data voltage of a 2D data format or a data voltage of a 3D data format to the image display panel, a controller configured to control the driving circuit in a 2D mode for displaying the 2D image or a 3D mode for displaying the 3D image, and a patterned retarder including a first retarder and a second retarder that are arranged line by line, the patterned retarder configured to divide the 3D image from the image display panel into a first polarization component and a second polarization component, the patterned retarder being aligned so that boundary portions of the first and second retarders are positioned in a center of pixels positioned on odd-numbered horizontal lines or even-numbered horizontal lines of the image display panel.