We propose a large parallax barrier by use of aperture grille.Main advantages of using aperture grille include no reflection and no absorption in apertures,as well as wide viewing angle.These advantages are investigated with theoretical calculations and experiments by use of several kinds of LED panels,such as a fine-pitch LED panel and a 140-inch large LED panel.Limitations of viewing angle by parallax barrier are analyzed in conventional black stripes on a transparent substrate type and in aperture grille type.Experimental results show use of aperture grille increases contrast and reduce reflection on the aperture surface. We propose a large parallax barrier by use of aperture grille. Main advantages of using aperture grille include no reflection and no absorption in apertures, as well as wide viewing angle. These advantages are investigated with theoretical calculations and experiments by use of several kinds of LEDs panels, such as a fine-pitch LED panel and a 140-inch large LED panel. Limits of viewing angle by parallax barrier are analyzed in conventional black stripes on a transparent substrate type and in aperture grille type. Experimental results show use of aperture grille increases contrast and reduce reflection on the aperture surface.