The invention relates to a reflecting cell including at least two substrates covered by an electrode and facing each other, the substrates delimiting between them a volume which separates them and which is filled with a cholesteric liquid crystal-type material, both electrodes being intended to be connected to a voltage source. This cell includes at least one half-wave plate arranged between both substrates and dividing the volume into two compartments, each enclosing a part of a same cholesteric liquid crystal.

A display system includes a backlight configured to project light including a housing and one or more light emitting elements received in the housing and one or more reflective portions disposed on the housing. A first display unit is disposed proximate the backlight includes a liquid crystal layer and at least one reflective polarizer. A second display unit is disposed proximate the first display unit. The second display unit includes a TFT display layer and at least one linear polarizer. At least one microcontroller is in communication with one or more of the backlight, the first display unit and the second display unit. The at least one microcontroller executes instructions to adjust the liquid crystal layer of the first display unit between a first transmissive state and a second transmissive state.

A touch screen panel may include a liquid crystal, a first transparent electrode and a second transparent electrode provided at both sides of the liquid crystal, and a controller configured to transfer image data to the first transparent electrode and the second transparent electrode in a first mode and sense a touch of a user on at least one of the first transparent electrode and the second transparent electrode in a second mode.

A backlight unit includes a light guide plate; a light source provided on a side surface of the light guide plate, and configured to inject light into the light guide plate; a circular polarizing reflective layer provided on a front surface of the light guide plate, and configured to reflect a first polarizing component and transmit a second polarizing component among components of light emitted from the light guide plate; and a cholesteric liquid crystal layer provided on the front surface of the circular polarizing reflective layer and including a plurality of regions, and configured to reflect or transmit the second polarizing component that has passed through the circular polarizing reflective layer according to a voltage applied to each of the plurality of regions.

According to an embodiment, an electrically switchable mirror includes: a first electrically switchable layer of cholesteric liquid crystal material, the first electrically switchable layer having a first state in which right-handed circularly polarized light incident thereon is reflected and left-handed circularly polarized light incident thereon is transmitted and a second state wherein right-handed and left-handed circularly polarized light incident thereon are transmitted; a second electrically switchable layer of cholesteric liquid crystal material, the second electrically switchable layer having a first state in which left-handed circularly polarized light incident thereon is reflected and right-handed circularly polarized light incident thereon is transmitted and a second state wherein right-handed and left-handed circularly polarized light incident thereon are transmitted; and a first electrically switchable wave plate disposed between the first and second electrically switchable layers.

An optical system with an electronically variable iris. The optical system comprises an optical lens. A number of transparent conductive layers is coupled to an optical surface of the optical lens. A liquid crystal film is separated into a number of portions by the number of transparent conductive layers, wherein a transmissive state of each portion, from the number of portions of the liquid crystal film, with respect to light is configured to change in response to application of a voltage to the number of transparent conductive layers.

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.

According to one embodiment, a liquid crystal display device includes a first liquid crystal device, a second liquid crystal device, and a liquid crystal display panel, the first liquid crystal device including a first substrate including a first electrode thereon, a second substrate including a second electrode thereon, and a first cholesteric liquid crystal layer, the second liquid crystal device including a third substrate including a third electrode thereon, a fourth substrate including a fourth electrode thereon, and a second cholesteric liquid crystal layer, wherein the first liquid crystal device and the second liquid crystal device are stacked successively.

A reflective liquid crystal display device includes: first to fourth substrates spaced apart from and parallel to each other; a first stack including a first pixel electrode, a first alignment layer, a first common electrode, a second alignment layer and a first cholesteric liquid crystal layer between the first and second alignment layers; a second stack including a second pixel electrode, a third alignment layer, a second common electrode, a fourth alignment layer and a second cholesteric liquid crystal layer between the third and fourth alignment layers; a third stack including a third pixel electrode, a fifth alignment layer, a third common electrode, a sixth alignment layer and a third cholesteric liquid crystal layer between the fifth and sixth alignment layers; and a fourth stack including a first mode electrode, an ion storing layer, an electrolyte layer, an electrochromic layer and a second mode electrode sequentially on the first substrate.

An optical device includes a light source and a polarization selective optical element. The polarization selective optical element includes a stack of a plurality of cholesteric liquid crystal layers. The plurality of cholesteric liquid crystal layers includes a first cholesteric liquid crystal layer with liquid crystal molecules arranged in a first helical configuration having a first pitch range for light of a first wavelength range and a second cholesteric liquid crystal layer with liquid crystal molecules arranged in a second helical configuration having a second pitch range for light of a second wavelength range. The second wavelength range is different from the first wavelength range.