A display device comprises a display panel (24), a light blocking arrangement for selectively blocking light which is directed to a lateral output direction from the display panel and an array of lenses (27). The display has a privacy mode in which the light blocking arrangement blocks laterally directed light output from the display device and a public mode in which the light blocking arrangement allows light to pass which is directed to a lateral output direction. The light blocking arrangement comprises a stack of layers (80), each layer comprising a pattern of light blocking arrangement portions of two different types (90,92) such that in the stack of layers, the portions align to form light blocking members, each light blocking member being aligned with an respective lens. The repeating pattern of the light blocking members has a pitch which is double the lens pitch. This enables the light blocking arrangement to be manufactured more easily.