According to one embodiment, a polarization conversion element includes a first substrate including a first plane electrode and a first control electrode, a second substrate, and a liquid crystal layer. The first control electrode comprises a first strip electrode, a second strip electrode, a third strip electrode, and a first common electrode. The first strip electrode and the first common electrode are orthogonal to each other, respective extension directions of the first to third strip electrodes are different from each other, and an angle formed by the first strip electrode and the third strip electrode is greater than an angle formed by the first strip electrode and the second strip electrode.

Provided is an optical scanning device having a stable scanning direction corresponding to a temperature fluctuation of a semiconductor laser by being provided with a predetermined liquid crystal optical element utilizing a characteristic of a linear expansion coefficient of a support of a liquid crystal diffraction element. An optical scanning device includes: a light source; and a light deflection element, in which the light deflection element includes a support and an optically anisotropic layer which is a cured layer of a liquid crystal composition, an optical axis of a liquid crystal compound contained in the liquid crystal composition is parallel to a surface of the optically anisotropic layer, and the optically anisotropic layer has a liquid crystal alignment pattern which is arranged along at least one in-plane direction of the optically anisotropic layer and in which an orientation of the optical axis of the liquid crystal compound changes continuously and rotationally, and the support satisfies Conditional Expression (1): |dλ/(dt×λ0)−α|<2×10.sup.−4.

A one-way glass with switching modes includes an absorbing layer located on a weak light side, a reflecting layer located on an intense light side, and a converting layer stacked between the absorbing layer and the reflecting layer. The absorbing layer absorbs first polarized light and allows second polarized light to pass through. The reflecting layer reflects the first polarized light and allows the second polarized light to pass through. Unpolarized light incident from the weak light side or from the intense light side is respectively converted into the polarized light. During the process of gradually adjusting the converting layer from a twisted state to a vertical state, rotated angles of polarization directions of the first polarized light and the second polarized light gradually decrease.

A U-shaped unit and a liquid crystal element with U-shaped coplanar electrode units provided by the invention are capable of increasing a horizontal electric field intensity in a power supply state, so that when the invention is applied to be used as a liquid crystal driving element, a required horizontal electric field intensity can be achieved with a lower driving voltage to reduce a required driving power when the liquid crystal element is used as a display screen, thereby achieving an effect of power saving.

There is provided a liquid crystal composition including at least one compound represented by General Formula (i) and at least one compound represented by General Formula (N). The total amount of the compound represented by General Formula (i) is 10% by mass or greater. In the liquid crystal composition and the liquid crystal display element using the composition, the liquid crystal composition has a positive Δ∈ and a flat transmission characteristic curve. Therefore, gradation characteristics are easily controlled. Furthermore, display defects due to burn-in, dropping marks, and the like can be suppressed, and therefore excellent display quality is exhibited. The liquid crystal display element using this liquid crystal composition can be also provided.

The present invention provides a liquid crystal display device in a new display mode that is based on the horizontal alignment capable of giving a wide viewing angle and that can achieve high speed response. The liquid crystal display device includes: a first substrate that includes a pair of electrodes; a second substrate that includes a pixel electrode and a common electrode; and a liquid crystal layer that contains liquid crystal molecules aligned horizontally, at least one of the pair of electrodes including a first linear portion that extends in a first direction, at least one of the pixel electrode and the common electrode including a second linear portion that extends in a second direction intersecting the first direction, the liquid crystal molecules being aligned in a direction perpendicular or parallel to the first direction in a first display state in which voltage is applied between the pair of electrodes but voltage is not applied between the pixel electrode and the common electrode, the liquid crystal molecules being aligned in a direction different from the alignment direction of the first display state, in a second display state in which voltage is applied between the pair of electrodes and voltage is applied between the pixel electrode and the common electrode.

The present invention provides a liquid crystal display device that may realize a wide viewing angle and realize a high-speed response. The liquid crystal display device of the present invention is a liquid crystal display device that has upper and lower substrates and a liquid crystal layer which is interposed between the upper and lower substrates, in which the lower substrate includes electrodes, the electrodes are configured with a first electrode, a second electrode in a different layer from the first electrode, and a third electrode in a same layer as the second electrode, the liquid crystal layer includes liquid crystal molecules that are horizontally aligned with respect to a main surface of the upper and lower substrates in a case where a voltage is not applied, and the liquid crystal display device is configured to execute a driving operation that causes the electrodes to generate an electric field which causes a portion of the liquid crystal molecules to rotate in a horizontal plane with respect to the main surface and causes another portion of the liquid crystal molecules to rotate in an opposite direction to the portion of the liquid crystal molecules in the horizontal plane with respect to the main surface.

An object of the present invention is to provide a composition that has positive Δε, exhibits a liquid crystal phase over a wide temperature range, has low viscosity, excellent solubility at low temperatures, and high resistivity and voltage holding ratio, and is stable against heat and light. By using this composition, IPS or TN liquid crystal display devices and the like that have excellent display quality and suppress display failures such as image-sticking and drop marks are provided in high yield. Provided is a composition that contains at least one selected from the group consisting of compounds represented by general formulae (i) and (ii) and at least one compound represented by general formula (iii). Also provided is a liquid crystal display device that uses the composition and an IPS or FFS device that uses the composition.

A first substrate (10) in a liquid crystal display device (100) includes a first electrode (11) provided in each pixel and a second electrode (12) generating a lateral electric field in a liquid crystal layer (30) together with the first electrode. A second substrate (20) includes a third electrode (21) generating a vertical electric field in the liquid crystal layer together with the first electrode and the second electrode. Each pixel exhibits, in a switched manner, a black display state where black display is provided in a state where the vertical electric field is generated in the liquid crystal layer, a white display state where white display is provided in a state where the lateral electric field is generated in the liquid crystal layer, and a transparent display state where a rear side of a liquid crystal display panel (1) is seen through in a state where no voltage is applied to the liquid crystal layer. A potential difference between the first electrode and the second electrode at each gray scale level from a lowest level to a highest level is 60% or less of a potential difference between the second electrode and the third electrode in the black display state.

Each of pixels of a liquid crystal display device (100) exhibits, in a switched manner, a black display state where black display is provided in a state where a vertical electric field is generated in a liquid crystal layer (30), a white display state where white display is provided in a state where a lateral electric field is generated in the liquid crystal layer, and a transparent display state where a rear side of a liquid crystal display panel (1) is seen through in a state where no voltage is applied to the liquid crystal layer. A gray scale level group including gray scale levels from a lowest level to a highest level includes a white level corresponding to the white display state, a transparent level corresponding to the transparent display state and having a luminance higher than that of the white level, and a plurality of sub-transparent levels each having a luminance higher than that of the white level and lower than that of the transparent level.