Provided are a retardation film that has a high heat resistance, has excellent formability and handleability even in a single-layer structure, has a negative thickness-direction retardation Rth value, and is suitable as a negative A-plate or a positive C-plate and a method for producing the film. The retardation film is formed of a stretched film of a polyester resin, contains a unit (A1) represented by the formula (1) as a diol unit (A) and a unit (B1) represented by the formula (2a) or (2b) as a dicarboxylic acid unit (B), and is a negative A-plate or a positive C-plate.

##STR00001##

In the formulae, Z.sup.1 and Z.sup.2 represent an aromatic hydrocarbon ring, R.sup.1, R.sup.2a, R.sup.2b, R.sup.3a and R.sup.3b represent a substituent, k, p1 and p2 denotes an integer of 0 to 8, q denotes an integer of 0 to 4, m1, m2, n1 and n2 denotes an integer of not less than 0, A.sup.1a and A.sup.1b represents an alkylene group, and A.sup.2a, A.sup.2b and A.sup.3 represents a divalent hydrocarbon group.

An optical device includes a first layer including a first birefringent material having a negative birefringence dispersion property. The optical device also includes a second layer including a second birefringent material having a positive birefringence dispersion property. The first layer and the second layer are structurally patterned to provide at least one predetermined optical function.

An optical device is provided. The optical device includes a first optical element configured to output an elliptically polarized light having one or more predetermined polarization ellipse parameters. The optical device also includes a second optical element including a birefringent material with a chirality, and configured to receive the elliptically polarized light from the first optical element and reflect the elliptically polarized light as a circularly polarized light.

An optical element is provided. The optical element includes a positive-C film including a liquid crystal (“LC”) layer. The optical element also includes a positive-A film. The optical element also includes a negative biaxial retardation film disposed between the positive-A film and the positive-C film.

An electronic device is provided. The electronic device includes a first substrate and a second substrate. The second substrate is disposed opposite to the first substrate. A light control layer is disposed between the first substrate and the second substrate, and the light control layer includes a first optical axis. A negative phase retardation layer is disposed between the first substrate and the second substrate. The negative phase retardation layer includes a second optical axis. The first optical axis and the second optical axis are parallel to each other.

A digital neutral density (DND) filter that provides rapid reconfiguration between discrete density states using electro-optic devices such as liquid-crystal cells. Each filter stage may be dedicated to binary switching between a high-transmission state (giving minimal loss) and one or more prescribed densities in a filtering state. The design prescription may “hard-wire” a stage to produce switching between an all-pass filter and a prescribed filter density. Design parameters can be used to assign specific densities to each stage. Multiple stages can be cascaded to provide a plurality of discrete density values. Such DND filters can sacrifice analog tunability in order to optimize uniformity in color and transmission over a wide range of incidence angles.

The present application relates to a retardation film including a composition or a cured product thereof, the composition comprising: an acrylate-based resin having a glass transition temperature (Tg) of 120° C.; or more; a retardation adjusting agent comprising a styrene monomer; and a triazine-based birefringence adjusting agent, in which the triazine-based birefringence adjusting agent is included in an amount of more than 5 parts by weight and 15 parts by weight or less, based on 100 parts by weight of the acrylate-based resin; a polarizing plate comprising the same, and a liquid crystal display device comprising the same.

The present invention provides a liquid crystal display device of a transverse electric field mode that may inhibit internal reflection and realize proper black display to which coloring does not occur. The present invention provides a liquid crystal display device including a first linear polarizer, a first λ/4 retardation layer, a first substrate, a second λ/4 retardation layer configured with a different material from the first λ/4 retardation layer, a liquid crystal layer that contains liquid crystals which are horizontally aligned in a case where no voltage is applied, plural electrode pairs that generate a transverse electric field in the liquid crystal layer by a voltage being applied, a second substrate, a second linear polarizer, and a backlight. In a case where a color of light emitted from the backlight is expressed by using chromaticity coordinates (x, y) of an XYZ color system, both of x and y are 0.32 or greater. The plural electrode pairs include a red electrode pair arranged in a red sub-pixel, a green electrode pair arranged in a green sub-pixel, and a blue electrode pair arranged in a blue sub-pixel. A white display applied voltage of the blue electrode pair is different from the white display applied voltage of the red electrode pair and the white display applied voltage of the green electrode pair.

Provided is a liquid crystal display device, comprising an upper polarizer, an in-plane switching mode liquid crystal panel, and a lower polarizer. The in-plane switching mode liquid crystal panel comprises a liquid crystal layer having a Rin (550) value in a range of 310 nm to 350 nm. An absorption axis of the upper polarizer and an absorption axis of the lower polarizer are orthogonal. The lower polarizer is adjacent to a light source as compared to the upper polarizer. The liquid crystal display further comprises, as retardation films, a positive biaxial retardation film having a Rin (450)/Rin (550) value in a range of 0.99 to 1.01, and a negative C plate between the upper polarizer and the in-plane switching mode liquid crystal panel.

A display substrate and a manufacturing method thereof and a display panel. The display substrate includes a display area and a reflective layer, and at least a portion of the reflective layer is in the display area. The reflective layer includes a metasurface facing a display side of the display substrate, and the metasurface includes a plurality of convex structures which have metamaterial properties and are scattered.