The present invention provides a display panel in which deterioration of color tone may be suppressed regardless of the reflectance of the display element. A display panel including a display element (A), a retardation layer (B) positioned upon the light emission surface side of the display element, and a polarizer (C) positioned upon the light emission surface side of the retardation layer, in which the retardation layer (B) has a ?/4 retardation layer (B1), and the in-plane retardation of the ?/4 retardation layer (B1) satisfies the following Condition 1: <Condition 1> The spectral reflectance of the display element is measured by an SCI method, the average reflectance at wavelengths over the range of 400 nm or more and less than 550 nm is obtained as R.sub.1, the average reflectance at wavelengths over the range of 550 nm or more and less than 700 nm is obtained as R.sub.2, and when the value of R.sub.1/R.sub.2 is calculated and obtained as x, the in-plane retardation of the ?/4 retardation layer falls within the range of ?4.6002x+119.24 nm or more and ?4.6002x+129.24 nm or less.

Nonlinear optical chromophore compositions which display lyotropic nematic liquid crystal phases in polar organic solvents and provide a mechanical anisotropic effect allowing for the formation of a non-centrosymmetric chromophore-polymer matrix without the application of an electric field.

Described herein are heterocyclic liquid crystal compositions that can allow for the adjustment of their refractive indices by the application of an electric field, such as those described by the following formula (1) wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, X, Y are as described herein. In addition, selectively dimmable reverse-mode polymer dispersed liquid crystal (PDLC) elements and devices using the aforementioned compositions are also described, which are transparent when no voltage is applied and opaque when a voltage is applied.

Disclosed herein is a light emitting device and method of manufacturing such a device comprised of a series of photopolymerizable, chiral liquid crystalline layers that can be solvent cast on a substrate. The mixture of chiral materials in each successive layer may be blended in such a way that each layer has the same chiral pitch. Further the chiral materials in each layer may also be blended so that the ordinary and extraordinary refractive indices in each layer match the other layers such that the complete assembly of layers will optically function as a single relatively thick layer of chiral liquid crystal. The chiral nematic material in each layer can spontaneously adopt a helical structure with a helical pitch. The light emitting layers of the light emitting device can further comprise electroluminescent material that emits light into the band edge light propagation modes of the photonic crystal.

The present invention relates to heteroaromatic compounds which have two different reactive groups, their use in the synthesis of asymmetrically substituted compounds, and synthesis processes in which the compounds according to the invention are reacted sequentially with two different compounds, whereby an asymmetrically substituted compound is formed.

Nonlinear optical chromophore compositions which display lyotropic nematic liquid crystal phases in polar organic solvents and provide a mechanical anisotropic effect allowing for the formation of a non-centrosymmetric chromophore-polymer matrix without the application of an electric field.

Novel dithiopyrrolopyrrole derivatives having dichroic properties which have very high photostability in solution in a liquid-crystalline host are proposed.

A family of low-molecular-weight, main-chain thermotropic liquid-crystalline polyimides (TLC-PI) that are crosslinkable is disclosed. These all-aromatic TLC-PI are derived from (i) wholly aromatic and flexible diamine monomers, in which the linkage between the two aniline-ends contains a relatively high heat-tolerant but flexible chain constituted by two or more units of 1,4-phenoxy or 1,3-phenoxy or in combinations of both. Processes of making and using such all-aromatic TLC-PI is also provided.

The invention relates to novel polymers containing repeating units based on benzodithiophene or derivatives thereof, monomers and methods for their preparation, their use as semiconductors in organic electronic (OE) devices, especially in organic photovoltaic (OPV) devices, and to OE and OPV devices comprising these polymers.

An optically anisotropic layer is formed by a liquid crystal compound represented by General Formula 1, in which the long axes of the molecules are oriented.

##STR00001##

wherein L.sub.1 and L.sub.2 independently represent a linking group having a carbonyl group; F.sub.1 and F.sub.2 independently represent an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom; n and m independently represent an integer from 0 to 4; a and b independently represent an integer from 1 to 4; T.sub.1 and T.sub.2 independently represent a spacer portion including a straight chain or branched alkylene or alkylene oxide group having 2 to 20 carbon atoms; and Ar represents a divalent group having at least one aromatic ring selected from a group consisting of aromatic hydrocarbon rings and aromatic heterocycles, the number of electrons in the Ar group being 8 or greater.