Dual directional view (DDV) displays show different images to different viewers. For example, the driver of a car looking at a central DDV display could view navigation information, while the passenger, looking from a different angle, could be watching a movie. This technology, which has now established itself on the dashboards of high-end Jaguar, Mercedes, and Range Rover cars, is manufactured by Sharp Corporation using a well-known parallax barrier technique. Unfortunately parallax barriers are associated with an inevitable drop in brightness compared with a single view display. A parallax barrier-based DDV display typically has less than half the transmission of a single view display. Here we present a solution to these problems via the use of a combined microlens and parallax barrier system, which can not only boost the brightness by 55% from a parallax barrier-only system but increase the head freedom by 25% and reduce crosstalk also. However, the use of microlenses (which must be positioned between the polarizers of the LCD) can adversely affect the contrast ratio of the display. Careful choice of the LCD mode is therefore required in order to create a DDV display that is both high in brightness and contrast ratio. The use of a single-domain vertically aligned nematic (VAN) liquid crystal (LC) mode, together with a microlens plus parallax barrier system can achieve this with a contrast ratio of measured at 30° to normal incidence.
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