A liquid crystal display device includes a first substrate, a liquid crystal layer, a second substrate, a retardation layer, and a polarizer in this order from a back face side, and includes a plurality of pixels arrayed in a matrix shape, in which the first substrate includes a reflective layer that reflects light, a first electrode and a second electrode that are capable of generating a transverse electrical field in the liquid crystal layer, and a first horizontal alignment film that is in contact with the liquid crystal layer, the second substrate includes a second horizontal alignment film in contact with the liquid crystal layer, the retardation layer includes a /4 plate and a /2 plate, the liquid crystal layer includes a positive-type liquid crystal material or a negative-type liquid crystal material, and has a twist alignment when no voltage is applied, and an angle formed by a polarization axis of the polarizer and an alignment direction of liquid crystal molecules defined by the first horizontal alignment film is within a predetermined range.

A reflective polarization rotator based on a twisted nematic (TN) liquid crystal (LC) configuration may be optimized for achromatic performance in both bright and dark states by compensating wavelength dependence of polarization transformation by the TN LC layer. At linear achromatic input polarization, the compensation aims to provide a circular achromatic polarization at the reflector, which guarantees the achromaticity of the 90 degrees polarization rotation on double pass. The compensation takes care to preserve linear polarization at the reflector when the LC device is driven to a vertical LC director configuration. Such an approach ensures that the performance of the polarization rotator is achromatic in both driven and undriven states of the LC device.

A reflective display apparatus is provided, which includes a liquid-crystal-on-silicon (LCOS) display module and a compensation layer. The LCOS display module has a liquid crystal layer. The liquid crystal layer includes liquid crystal cells, each having a beta angle ranging from about 9 degrees to about 11 degrees and a twist angle ranging from about 84 degrees to about 88 degrees relative to the beta angle. The compensation layer is disposed on the LCOS display module for compensating retardation of the liquid crystal layer.

A display panel includes a first polarizer, two twisted nematic cells, a second polarizer, and a display. The first twisted nematic cell transfers light in response to a first control signal. In an off state, a polarity of the light is rotated in a first twist. In an on state, the polarity of the light is maintained. The second twisted nematic cell transfers the light in response to a second control signal. In the off state, a polarity of the light is rotated in a second twist. In the on state, the polarity of the light is maintained. The display generates an image in the light in response to a display signal. While the twisted nematic cells are in the off state, the image is viewable in a public viewing angle. While the twisted nematic cells are in the on state, the image is viewable in a private viewing angle.

A liquid crystal display device includes a first substrate, a liquid crystal layer, a second substrate, a retardation layer, and a polarizer in this order from a back face side, and includes a plurality of pixels arrayed in a matrix shape, in which the first substrate includes a reflective layer that reflects light, a first electrode and a second electrode that are capable of generating a transverse electrical field in the liquid crystal layer, and a first horizontal alignment film that is in contact with the liquid crystal layer, the second substrate includes a second horizontal alignment film in contact with the liquid crystal layer, the retardation layer includes a /4 plate and a /2 plate, the liquid crystal layer includes a positive-type liquid crystal material or a negative-type liquid crystal material, and has a twist alignment when no voltage is applied, and an angle formed by a polarization axis of the polarizer and an alignment direction of liquid crystal molecules defined by the first horizontal alignment film is within a predetermined range.

An object of the present invention is to provide a wavelength selective phase difference plate in which a difference between a phase difference generated in a case where light is incident from a front direction and a phase difference generated in a case where light is incident from an oblique direction is small. The wavelength selective phase difference plate of the present invention includes a plurality of wavelength plates, in which the wavelength selective phase difference plate changes a phase of polarized light in a first wavelength range and does not change a phase of polarized light in a second wavelength range which is different from the first wavelength range, slow axis orientations of the plurality of wavelength plates are different from each other, and Nz factors of the plurality of wavelength plates are each more than 0.3 and less than 0.7.

An optical unit that enables observation of an image with reduced brightness unevenness, and an image display system including the unit, are provided. The optical unit includes first and second partial reflection elements that reflect part of incident light and transmit part of it, and a polarization diffraction element including a liquid crystal layer. The liquid crystal layer has an alignment pattern in which an optical axis orientation continuously rotates in one in-plane direction. Regions of the layer have different single period lengths, where a single period is defined as a 180 rotation of the optical axis. The layer also includes regions where the optical axis is twisted in the thickness direction and regions with different total twisted angles.