A display device is provided that comprises a liquid crystal display panel for displaying an image by spatial light modulation, and circuitry for switching liquid crystal in the panel between having a first configuration in a first mode to cause an image displayed using the panel to be discernible from a wide range of viewing angles, and having a second configuration in a second mode to cause an image displayed using the panel to be discernible substantially only from within a narrow range of viewing angles. Several types of display panel to achieve such in-panel switching between public and private viewing modes are disclosed.