A switchable privacy display apparatus comprises a polarised output spatial light modulator, and an additional polariser. A reflective polariser, switchable liquid crystal polar control retarder, passive polar control retarders and air gap are arranged between the display output polariser and additional polariser. The passive retarders are arranged to provide no phase difference to polarised light from the spatial light modulator for on-axis light; and simultaneously provide a non-zero phase difference for polarised light in off-axis directions. The polar control retarders are further arranged to achieve low reflectivity for light propagating through the air gap. A switchable privacy display that can be conveniently assembled at low cost can be provided with high contrast images for display users while maintaining high visual security level for off-axis snoopers.

The present invention provides a liquid crystal display device that includes a first substrate having an electrode A formed thereon; a second substrate having an electrode B formed thereon and being disposed to oppose the first substrate; and a liquid crystal layer disposed between the first substrate and the second substrate and substantially vertically aligned with respect to the first and second substrates when no voltage is applied between electrodes, in which the electrode A has a fishbone pattern having a branched portion, and a space (S μm) between adjacent branches of branches of the fishbone pattern and an inter-substrate distance (d μm) between the first substrate and the second substrate satisfy a relationship of formula (1):
(d−0.6)/1.25<S<(d+1.1)/1.25  formula (1).

A display panel is provided. The display panel includes pixel electrodes, and black matrices located between adjacent pixel electrodes. Opaque regions are formed between the pixel electrodes. Dark strip regions are formed at part of edges of pixel electrodes. The black matrices cover the opaque regions and the dark strip regions. The provided display panel increases an area of a display region by oppositely disposing the black matrices and the pixel electrodes.

An imaging directional backlight apparatus including a waveguide, a light source array, for providing large area directed illumination from localized light sources. The waveguide may include a stepped structure, in which the steps may further include extraction features optically hidden to guided light, propagating in a first forward direction. Returning light propagating in a second backward direction may be refracted, diffracted, or reflected by the features to provide discrete illumination beams exiting from the top surface of the waveguide. The directional backlight may be arranged to switch between at least a first wide angular luminance profile mode and a second narrow angular luminance profile mode. The directional backlight is arranged to illuminate an LCD with a bias electrode arranged to switch liquid crystal directors in black state pixels between a first wide angular contrast profile mode and a second narrow angular contrast profile mode. Performance of privacy operation for off-axis snoopers is enhanced in comparison to displays with only directional backlights or switchable contrast properties.

The invention relates to a liquid-crystalline medium comprising one or more compounds of the formula IA and, one or more compounds of formula BS

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wherein the occurring groups have the meanings indicated in claim 1, and to the use thereof in an active-matrix display, in particular in a VA, IPS, U-IPS, FFS, UB-FFS, SA-VA, SA-FFS, PS-VA, PS-OCB, PS-IPS, PS-FFS, PS-UB-FFS, PS-posi-VA, PS-TN, polymer stabilised SA-VA or polymer stabilised SA-FFS display.

A control system for a switchable privacy display apparatus comprises sensors arranged to determine device location, operating environment, document type, application type and further comprises a privacy policy for control of privacy images. High image visibility is provided for public mode operation while in privacy mode a high visual security level may be obtained by means of control of image luminance, contrast and white point in response to the privacy policy.

A switchable privacy display apparatus comprises a polarised output spatial light modulator, and an additional polariser. A reflective polariser, switchable liquid crystal polar control retarder, passive polar control retarders and air gap are arranged between the display output polariser and additional polariser. The passive retarders are arranged to provide no phase difference to polarised light from the spatial light modulator for on-axis light; and simultaneously provide a non-zero phase difference for polarised light in off-axis directions. The polar control retarders are further arranged to achieve low reflectivity for light propagating through the air gap. A switchable privacy display that can be conveniently assembled at low cost can be provided with high contrast images for display users while maintaining high visual security level for off-axis snoopers.

A display panel and a method for fabricating the same are provided. The display panel includes a first substrate, a first protrusion, a first liquid crystal layer, a third liquid crystal layer, a second liquid crystal layer, a second protrusion, and a second substrate in order from top to bottom. The first liquid crystal layer, the second liquid crystal layer, and the third liquid crystal layer include negative type liquid crystal molecules. An absolute value of a dielectric anisotropy parameter of the liquid crystal molecules in the first liquid crystal layer and an absolute value of a dielectric anisotropy parameter of the liquid crystal molecules in the second liquid crystal layer are both greater than an absolute value of a dielectric anisotropy parameter of the liquid crystal molecules in the third liquid crystal layer.

An infrared reflection device includes a power supply assembly, a plurality of switches, and two relatively disposed light-transmitting conductive substrates packaging a regulating area. Each of the light-transmitting conductive substrates comprise a light-transmitting substrate and an electrode layer. The regulating area is filled with a liquid crystal mixture; the electrode layers are arranged on opposite surfaces of the two light-transmitting substrates; the electrode layer of at least one of the light-transmitting conductive substrates comprises at least two mutually independent electrode areas; and electrode areas of the same light-transmitting conductive substrate, after being respectively connected in series to the switches, are jointly connected in parallel to the same electrode of the power supply assembly.

A privacy display comprises a polarised output spatial light modulator, reflective polariser, plural polar control retarders and a polariser. In a privacy mode of operation, on-axis light from the spatial light modulator is directed without loss, whereas off-axis light has reduced luminance. Further, display reflectivity is reduced for on-axis reflections of ambient light, while reflectivity is increased for off-axis light. The visibility of the display to off-axis snoopers is reduced by means of luminance reduction and increased frontal reflectivity to ambient light. In a public mode of operation, the liquid crystal retardance is adjusted so that off-axis luminance and reflectivity are unmodified.