An image display system comprises a first liquid crystal projector which projects a counterclockwise-rotating, circularly polarized light beam to form an image containing specific visual information on a screen and a second liquid crystal projector which projects a clockwise-rotating, circularly polarized light beam to form a white image on the same screen. When viewed with the naked eye, a combination of the two images projected on the screen appears totally white. A viewer wearing a dedicated viewing device equipped with an optical filter which allows counterclockwise-rotating, circularly polarized light to pass through can selectively see the image projected by the first liquid crystal projector.