Provided is a reflective screen and a projection image display system in which a transmittance of light can be selectively changed, a transmittance in a transparent state is sufficiently high, a voltage does not need to be applied constantly, and a voltage is applied to decrease a transmittance of light in a case where the reflective screen is irradiated with video light. The reflective screen includes: a light reflecting layer that is formed of a cholesteric liquid crystal layer and where a selective reflection wavelength at a polar angle of 60° is present in a visible range, in which senses of helix of all of cholesteric liquid crystal layers are the same and Expression (1) is satisfied; and a transparent first electrode, a transparent second electrode, and a light control layer that are provided on a rear side with respect to the light reflective layer, the light control layer being disposed between the first electrode and the second electrode, in which the light control layer includes a polymer network and liquid crystal molecules and changes between a first state where light is scattered and a second state where transmission of light is allowed by changing a magnitude of a voltage applied, the polymer network having a three-dimensional net shape having a plurality of domains, and the liquid crystal molecules being positioned in the domains.
R[−60,40](550)/R[−60,30](550)≥1.5  Expression (1)

A laminate is capable of forming an orientation film formed by orienting a rod-like liquid crystal compound or a disk-like liquid crystal compound having a horizontal orientation ability or a vertical orientation ability with respect to a surface of the laminate, on the surface, by using an orientation restraining force of the surface, the laminate including: a cholesteric liquid crystal layer. An optical film sequentially includes: a support; a cholesteric liquid crystal layer; and an orientation film.

The present invention provides a luminance-enhancing film including a λ/4 plate, and a reflection polarizer, including a first light reflection layer, a second light reflection layer, and a third light reflection layer from the λ/4 plate side sequentially, the light reflection layers being light reflection layers formed by fixing a cholesteric liquid crystalline phase, and including blue, green and red light reflection layers, and Rth(550) of the first light reflection layer and Rth(550) of the second light reflection layer having inverse signs; and a luminance-enhancing film including a λ/4 plate and a reflection polarizer including at least a light reflection layer formed of a rod-like cholesteric liquid crystal material and a light reflection layer formed of a disk-like cholesteric liquid crystal material. The luminance-enhancing film has high luminance and is able to suppress an oblique change in the color.

An optical element comprising: a cholesteric liquid crystal layer obtained by cholesteric alignment of a liquid crystal compound, in which the cholesteric liquid crystal layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from the liquid crystal compound changes while continuously rotating in at least one in-plane direction, a helical pitch of a helical axis direction in the cholesteric alignment gradually changes in a thickness direction of the cholesteric liquid crystal layer, and the cholesteric liquid crystal layer has a peak of reflection at each of a first wavelength λ and a second wavelength λ/2.

A liquid crystal display device, which comprises: a backlight source (1); a first handedness cholesteric liquid crystal film layer (2), located at an upper side of the backlight source (1) as a light emitting surface; an array substrate (3), located at an upper side of the first handedness cholesteric liquid crystal film layer (2); a color filter substrate (5), located at an upper side of the array substrate (3); and a second handedness cholesteric liquid crystal layer (4), sandwiched between the array substrate (3) and the color filter substrate (5), the first handedness being opposite to the second handedness. The liquid crystal display device greatly improves light efficiency and transmittance of the display and saves the processing steps and manufacturing costs.

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.

Embodiments of the present disclosure provides a transparent liquid crystal display device and a display method thereof. The transparent liquid crystal display device includes a transparent liquid crystal display panel and a transparent backlight module, the transparent liquid crystal display panel includes a color filter substrate, the transparent backlight module is disposed on a non-display side of the transparent liquid crystal display panel and includes a transparent light guide plate and an ultraviolet light source, the ultraviolet light source is disposed on a side end of the transparent light guide plate, the color filter substrate includes color resin lasers with different colors, and the color resin layers with different colors are mixed with fluorescent materials which are excitable to emit corresponding colors.

According to the invention, there is provided a mirror with an image display function including, in this order: an image display device; a ¼ wavelength plate; a circular polarization reflection layer; and a front surface plate made of glass or plastic, in which the circular polarization reflection layer includes a cholesteric liquid crystal layer, and the cholesteric liquid crystal layer has a central wavelength of selective reflection in a visible light region. The mirror with an image display function of the invention is capable of displaying a bright image.

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.

The present specification provides a multi-layer liquid crystal film including: a substrate; a first alignment film comprising an alignment material and an acrylate in which a weight ratio of the alignment material to the acrylate is 3:1 to 5:1; a first liquid crystal film provided on the first alignment film; a second alignment film provided on the first liquid crystal film; and a second liquid crystal film provided on the second alignment film, and a method for manufacturing a polarizing plate, the method including: laminating the multi-layer liquid crystal film to a polarizer and peeling off the substrate.