Abstract: In a liquid crystal display device, column signals intended to be applied to the liquid crystal material in first and second regions of the device are carried by first and second sets of column conductors disposed adjacent to a first substrate within the first and second regions, respectively. A portion of each second set conductor passes through the first region, but the singals thereon are prevented from being applied to the display material in the first region by using the first set conductors to shield from the display material that portion of each second set conductor which passes through the first region. In particular, the portion of each second set conductor that passes through the first region is disposed behind (relative to the display material) a respective first set conductor and is narrower than that first set conductor.

Abstract: A liquid-filled electro-optic display cell employs an elastomeric diaphragm to seal a filling orifice in the cell side wall. The orifice is surrounded by a rim and the diaphragm is retained over the rim in such a way as to seal the orifice while remaining free to flex over central portions of the orifice. This retention may be effected by means of an annular washer and clamping pin. In this way, sealing is effected and thermal expansion accommodated. The cell is filled by turning it until the orifice is uppermost and filling it until a convex meniscus is formed above the rim to ensure that the diaphragm seals the orifice without introduction of bubbles.

Abstract: The invention provides a two-channel liquid crystal light valve image projection system with prepolarization using an oil coupled optical arrangement. A prepolarizing beam splitter is mounted the container in optical alignment with a first surface for splitting and prepolarizing light from a source into first and second beams having first and second polarization states respectively. First and second dichroic separators are mounted within the container for extracting light of a first color from the first beam and light of a second color from the second beam respectively. The separator outputs are recombined by the prepolarizing prism into a single beam which is directed to a second polarizing beam splitter mounted within the container. The second beam splitter splits the single beam and directs light of the first and second polarizations through the second and third apertures, respectively.

Abstract: A four terminal liquid crystal display device includes orthogonally related row and column electrodes separated by a dielectric and disposed in respective sets above and below the liquid crystal medium. The electrodes in proximity to the LC medium are the column electrodes which have a small alternating square wave bias voltage.+-.Vo imposed therebetween so that a voltage of 2Vo magnitude is normally impressed across the LC medium. When an impulse voltage of magnitude 4Vo is impressed across the exterior row electrodes (+2Vo and -2Vo respectively), since the column electrodes are foraminated or have microapertures therethrough, the electric field established between the row and column electrodes in opposite sets, 3Vo, extends through the microapertures into the LC medium to establish a fringe electric field normal to the surfaces of the column electrodes tending to retain the LC directors in the vertical position.

Abstract: A method and an apparatus provide an optical switching system (100) which maintains essentially constant transmissivity at its maximum value and develops independent of viewing angle two system optical transmission states of substantially contaminant-free light. The system includes first and second light gates (102 and 104) of which each has associated therewith contaminant light intensity patterns (48 and 66) with points of local maxima (54, 56, 58, 60, 68, and 70) and local minima (62 and 72) in two system optical transmission states. Quarter-wave plates (134 and 136) are positioned between the light gates to develop circular polarization of light propagating between them. The presence of circularly polarized light maintains the system transmissivity at its maximum value while the relative orientation of the light gates is changed to align their contaminant light intensity patterns to block the transmission of contaminant light, and thereby improve the viewing angle performance.

Abstract: The disturbing residual transmission of a liquid crystal display device which is particularly noticeable in negative contrast devices is reduced by reference to the fact that the residual transmission is colored. The entire display surface of the liquid crystal device is provided with a transparent covering of a color complementary to the residual transmission color when the liquid crystal is not turned on. The transparent colored covering can be applied by printing as well as otherwise. In another embodiment, color shifts between turned-on and not turned-on displays are counteracted by mixing into the liquid crystal material a dichroic coloring material which has much lower absorption when the display is turned on. A light blue dichroic coloring material is suitable for LCDs which have residual transmission in the red region.

Abstract: In a matrix display device using the bistability effect of cholesteric liquid crystals, two supporting plates are provided with first and second pluralities of ridges. The electrodes of the liquid crystal extend across the second ridges onto the first ridges on which a separation strip separates the electrodes from one another. Liquid crystal orienting layers are provided over the entire surface of the supporting plate. The second ridges lying between the first ridges divide each picture element of the display into many sub-elements. Accordingly, the formation of focal-conical texture because of surface inhomogenities in the picture element display will be restricted to a single sub-element as a result of the homeotropic-nematic texture at the edges of the sub-element.

Abstract: An identification article, especially an identity document, has a marked element (8), e.g. a photograph covered by a mask (2) which is normally opaque but which, upon application of a suitable electric field changes to an at least translucent state. Preferably the mask (2) complies a liquid crystal layer (16) sandwiched between two plates (5 and 7) of which one plate is at least translucent.

Abstract: A liquid crystal display with a liquid crystal layer enclosed by two parallel plates which carry electrodes and on top thereof a first layer system of several dielectric electrodes having refractive indices smaller than 2.2 and a thickness of the layers above the base layer, under 200 nm. The liquid crystal display is characterized by the following features with respect to the first carrier plate.the electrode has a thickness d.sub.e, within the range according to 0<d.sub.e .ltoreq.30 nm or (m.lambda./2n.sub.e -10) nm.ltoreq.d.sub.e .ltoreq.(m.lambda./2n.sub.e +10) nm (.lambda.=550 nm, m=natural integer>0, n.sub.e =index of refraction of the electrode, nm=nanometer),the base layer has an index of refraction n.sub.b and a thickness d.sub.b, within the range according to 1.40.ltoreq.n.sub.b .ltoreq.1.50 and 20 nm.ltoreq.d.sub.b .ltoreq.50 nm or (m 300/n.sub.b -20) nm.ltoreq.d.sub.b .ltoreq.(m 300/n.sub.b +20) nm,the remaining layers of the first layer system have indices of refraction n.sub.

Abstract: A liquid crystal display device having high extinction ratio polarizers on the input and output sides of a transmissive, twisted nematic liquid crystal cell. The liquid crystal cell incorporating a dichroic dye which is admixed with the liquid crystal material. The high extinction ratio polarizers get the full contrast and density capability from the liquid crystal cell while the dichroic dye prevents the buildup of the contrast limiting orthogonal mode of the polarized light passing therethrough, thus, further increasing the optical contrast and density. Such an arrangement provides optical contrasts of around 150:1 with a 10 micron thick liquid crystal cell.

Abstract: A polar co-ordinate display of full 360.degree. arc comprised of electrode bearing substrates each side of a layer of dyed phase change liquid crystal material. One set of electrodes comprises concentric spirals, the other set comprises radials. The display is multiplex addressed using four select waveform signals. These four signals V.sub.1, V.sub.2, V.sub.3, and V.sub.x satisfy the following conditions:RMS(V.sub.x -V.sub.i)=V.sub.p, i=1, 2 or 3;RMS(V.sub.1 -V.sub.2)=V.sub.p ; RMS(V.sub.1 -V.sub.3)=V.sub.0where V.sub.p is an upper threshold voltage, and V.sub.0 a saturation voltage for dyed phase change hysteresis, and may be of the coded form;V.sub.1 =,1010,;V.sub.2 =,1100,;V.sub.3 =,0101,;V.sub.x =,0110,.These may be generated using two 2-bit registers with exclusive OR-gate feedback.

Abstract: A liquid crystal display comprises a layer of cholesteric or smectic liquid crystal material contained between a front and rear wall. A pen having a tip is caused to move across the front wall causing an observable change in the liquid crystal under the pen tip. The change in liquid crystal material may be between its grandjean or planar state and focal conic state. This change may be caused by local pen tip pressure, heat, light or electric field. Erasure of observed information is by flexing of the liquid crystal layer. Alternatively heating and cooling, or an electric field may be used to erase the information. A resistive layer covers the front wall so that the instantaneous position of the pen can be fed through bus bars to a computer. This computer compares the electrical version of an observed signature on the display with a stored signature.

Abstract: A liquid crystal display enclosing between two parallel plates a liquid crystal layer which can be switched between two optically different states. The plate surfaces facing each other each carry a matching layer on top of which are the electrodes. On top of the electrode is a first layer system with a dielectric layer and a topmost orientation layer. The refraction index n.sub.u of the substrata is smaller than the index n.sub.e of the electrode. The index of the matching layer has the following relationship: ##EQU1## The matching layer has a thickness d.sub.a, according to: ##EQU2## wherein .lambda.=550 nm, m=natural integer >0, and nm=nanometer, The electrode has a thickness d.sub.e, according to: d.sub.e .ltoreq.

Abstract: A brilliant liquid crystal display having the capability of a wide variety of coloration is disclosed utilizing a photoluminescent transflector for concentrating the internal light and ambient light into a narrow frequency range which is coordinated with the dye selected for the liquid crystal, resulting in an enhanced brightness for the display. Masking all regions of the liquid crystal display except for the selectively annunciating segments thereof, the resultant display is capable of a broad range of colors having a significantly enhanced luminance characteristic.

Abstract: The present invention relates to an omnidirectional reflector having a light source situated in the center thereof, said reflector being adapted to project a light distribution giving a generally even illumination on the plane under the reflector. This reflector is composed of a number of segments of reflector material which are arranged around the light source and turned helically in the vertical sense of the reflector, said segments at least substantially enclosing the light source and forming a symmetrical body.

Abstract: An external rear view mirror for motor vehicles, with a shell-shaped housing for receiving a mirror body which is preferably adjustable from the vehicle interior. The freely projecting part of the mirror housing is pivotably mounted on the housing base, and the gap between the freely projecting part on the one hand, and the housing base on the other hand, is adapted to be bridged by a flat seal. One edge of the seal is securely clamped, while the other edge engages releasably in, and is capable of being lifted from, a groove.

Abstract: The invention relates to an exterior mirror for vehicles, with a mirror-housing which, in normal operation, is retained in a fixed location on the vehicle and which, in the event of a collision, can fold away, forwards or backwards, until it assumes at least an approximately flat position against the vehicle. Folding occurs about a pair of pivot-axes. A mirror-shell, carrying a reflector, is retained in the interior of the mirror-housing. An aerodynamically efficient fairing is provided on the leading side of the mirror-housing. In order to be able to design the fairing with a shape which is particularly aerodynamically efficient, namely with a shape which is particularly long in the direction in which the vehicle travels and which resembles a wedge, while nevertheless being able, on the other hand, to permit the mirror to fold away effectively and with little overhang, at least one separate pivot-axis is provided for the fairing of the mirror-housing.

Abstract: The invention relates to a matrix display device with a plurality of sets of electrodes as well as to the process for controlling the same.The device comprises two insulating walls and by a material having a plurality of zones distributed in matrix-like manner and inserted between a first system of electrodes covering one of the two walls and defining p control columns and a second system of electrodes covering the other wall, constituted by parallel conductive strips, and defining q control lines, the column x.sub.i in which i is an integer such that 1.ltoreq.i.ltoreq.p and row y.sub.j in which j is an integer such that 1.ltoreq.j.ltoreq.q defining a zone x.sub.i y.sub.j of the material. The first system is constituted by a solid layer of electrodes and n sets of electrodes, which are electrically insulated from one another. The electrodes of this system being grouped in such a way that each group of electrodes corresponds to a single control row.

Abstract: An arrangement for optically creating a full width scanning array from a plurality of small scanning or writing arrays. The small arrays are disposed in alternating staggered relation in two parallel rows on a substrate with the array viewing fields overlapping to prevent discontinuity. The substrate bearing the arrays is placed in optical relation with an array of fiber optic lenses which transmit an image line to or from the arrays. A biprism array composed of plural prisms, one for each smaller array, is located between the substrate bearing the arrays and the lens array. To destagger the separated scanning arrays and produce a single uninterrupted full width scanning array, alternate ones of the prisms in the biprism array are reversed.

Abstract: An electro-optic device comprising a polarizing plate or a polarizing film is characterized in that said electro-optic device is provided with a plurality of projections on at least one of the surface of the polarizing plate or the polarizing film opposing to a substrate, and the surface of the substrate opposing to the polarizing plate or film.