An optical film includes a polarizer. The polarizer includes a base layer, and a material of the base layer is obtained by dyeing a base material with a dye. The base material includes a polyvinyl alcohol material, and the dye is selected from blue dichroism organic dyes.

A smart window includes two transparent substrates and a liquid crystal layer. The two transparent substrates are opposite to each other and are electrically connected to a voltage supply. A first pulse voltage or a second pulse voltage is provided between the two transparent substrates by the voltage supply. The liquid crystal layer is located between the two transparent substrates and has a liquid crystal material. The liquid crystal material has a pitch of at most 250 nanometers or at least 500 nanometers. The liquid crystal material includes a nematic liquid crystal, a rotatory molecule, and a photochromic dye mixed with each other. The liquid crystal material changes a transmittance corresponding to a specific light wavelength range when receiving a light. The liquid crystal material is switched between a planar texture and a focal-conic texture respectively according to the first pulse voltage and the second pulse voltage.

In the liquid crystal display panel, when no voltage is applied to a liquid crystal layer, a first tilt angle of liquid crystal molecules adjacent to a first vertical alignment film with respect to the first vertical alignment film and a second tilt angle of liquid crystal molecules adjacent to a second vertical alignment film with respect to the second vertical alignment film differ from each other. Any one of the first vertical alignment film and the second vertical alignment film is a photo-alignment film subjected to alignment process such that a plurality of domains, the alignment vectors of which differ from each other, are formed in a region of a display unit. The display unit includes the plurality of domains along a first direction of the display unit in a plan view, when a voltage is applied to the liquid crystal layer.

A device includes a polymer stabilized blue phase liquid crystal (“PS-BPLC”) layer. The device also includes an alignment structure coupled with the PS-BPLC layer. LC molecules disposed in contact with the alignment structure are configured to have a spatially varying in-plane orientation pattern that is at least partially defined by the alignment structure. The PS-BPLC layer is configured to forwardly deflect a polarized light having a predetermined handedness, and transmit a polarized light having a handedness that is orthogonal to the predetermined handedness.

A device includes a polymer stabilized blue phase liquid crystal (“PS-BPLC”) layer. The device also includes an alignment structure coupled with the PS-BPLC layer. LC molecules disposed in contact with the alignment structure are configured to have a spatially varying in-plane orientation pattern that is at least partially defined by the alignment structure. The PS-BPLC layer is configured to forwardly deflect a polarized light having a predetermined handedness, and transmit a polarized light having a handedness that is orthogonal to the predetermined handedness.

A smart window includes two transparent substrates and a liquid crystal layer. The two transparent substrates are opposite to each other and are electrically connected to a voltage supply. A first pulse voltage or a second pulse voltage is provided between the two transparent substrates by the voltage supply. The liquid crystal layer is located between the two transparent substrates and has a liquid crystal material. The liquid crystal material has a pitch of at most 250 nanometers or at least 500 nanometers. The liquid crystal material includes a nematic liquid crystal, a rotatory molecule, and a photochromic dye mixed with each other. The liquid crystal material changes a transmittance corresponding to a specific light wavelength range when receiving a light. The liquid crystal material is switched between a planar texture and a focal-conic texture respectively according to the first pulse voltage and the second pulse voltage.

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.

In the liquid crystal display panel, when no voltage is applied to a liquid crystal layer, a first tilt angle of liquid crystal molecules adjacent to a first vertical alignment film with respect to the first vertical alignment film and a second tilt angle of liquid crystal molecules adjacent to a second vertical alignment film with respect to the second vertical alignment film differ from each other. Any one of the first vertical alignment film and the second vertical alignment film is a photo-alignment film subjected to alignment process such that a plurality of domains, the alignment vectors of which differ from each other, are formed in a region of a display unit. The display unit includes the plurality of domains along a first direction of the display unit in a plan view, when a voltage is applied to the liquid crystal layer.

A display device includes a liquid crystal display panel including a first substrate, a second substrate facing the first substrate and including a reflective layer, and a liquid crystal layer disposed between the first and second substrates, a light control member disposed on the liquid crystal display panel and including a first optical part, and a polarizing member disposed on the light control member and including a polarizer. The liquid crystal layer includes a first liquid crystal molecule adjacent to the first substrate, and a long axis of the first liquid crystal molecule projected on the first substrate is aligned in a first direction. An extending direction of a long axis of the first optical part projected on the first substrate is parallel to the first direction, and the polarizer has a transmission axis extending in a second direction.

Simple and cost-effective measurement of polarization components or the complete PSoL (the so-called Stokes parameters) is achieved without any mechanical movements or deformation by using liquid crystal elements. A transmission of a first polarization of light is greater than a transmission of a second orthogonal polarization of light and transmission of the second polarization is greater than 5%. In another of the different states, the device has different levels of transmission of the first and second polarizations of light. At least two orthogonal polarization component values characterizing the light can be resolved by comparing an intensity of light captured in a plurality of the different states.