OPTICAL STACK FOR SWITCHABLE DIRECTIONAL DISPLAY DEVICE Russian patent published in 2022 - IPC G02F1/13363 

FIELD: optics.

SUBSTANCE: invention relates to switchable optical stacks for provision of control of illumination, when used in a display, including in a confidential display. The confidential display contains a spatial light modulator and a compensating switchable liquid-crystal slowing layer located between the first and the second polarizers installed in series with the spatial light modulator. In a confidential operational mode, light passes without losses along the main axis from the spatial light modulators, whereas light outside the main axis differs in reduced brightness. Display visibility outside the main axis is reduced for peeping people due to reduction in brightness within a wide polar field. In a wide-angle operational mode, the switchable liquid-crystal slowing layer is adjusted in such a way that brightness outside the main axis remains essentially without changes.

EFFECT: invention allows for an increase in brightness of a display, increase in the efficiency of adjustment of image visibility.

27 cl, 89 dwg, 12 tbl