A panel structure includes a glass layer, a plurality of first indium tin oxide (ITO) strips, a plurality of third indium tin oxide strips, a liquid crystal layer, a plurality of second indium tin oxide strips, and a plurality of fourth indium tin oxide strips. The panel structure operates in a grating mode during a first predetermined time. The first indium tin oxide strips receive a voltage, and the second indium tin oxide strips and the fourth indium tin oxide strips are grounded when the panel structure operates in the grating mode. The panel structure operates in a touch-sensing mode during a second predetermined time. The first indium tin oxide strips sequentially receive a driving voltage, and the fourth indium tin oxide strips detect a touch event when the panel structure operates in the touch-sensing mode. The grating mode and the touch-sensing mode of the panel structure are implemented alternately.