Abstract: The present invention relates to a process for the preparation of compounds of formula I wherein R1 and R2 are each independently of the other hydrogen or C1-C5alkyl and R3 is CF3 or CF2H, by a) reaction of a compound of formula II wherein R1 and R2 are as defined for formula I, with at least one reducing agent to form a compound of formula III wherein R1 and R2 are as defined for formula I, and b) reaction of that compound with at least one reducing agent to form a compound of formula IV wherein R1 and R2 are as defined for formula I, and (c) reaction of that compound with a compound of formula V wherein Q is chlorine, fluorine, bromine, iodine, hydroxy or C1-C6alkoxy and R3 is as defined for formula I, to form the compound of formula I; and to novel intermediates for use in that process.

Abstract: The present invention relates to a process for the preparation of compounds of formula I wherein R1 and R2 are each independently of the other hydrogen or C1-C5alkyl and R3 is CF3 or CF2H, by a) reaction of a compound of formula II wherein R1 and R2 are as defined for formula I, with at least one reducing agent to form a compound of formula III wherein R1 and R2 are as defined for formula I, and b) reaction of that compound with at least one reducing agent to form a compound of formula IV wherein R1 and R2 are as defined for formula I, and (c) reaction of that compound with a compound of formula V wherein Q is chlorine, fluorine, bromine, iodine, hydroxy or C1-C6alkoxy and R3 is as defined for formula I, to form the compound of formula I; and to novel intermediates for use in that process.

Abstract: The present invention relates to a process for the preparation of compounds of formula I wherein R1 and R2 are each independently of the other hydrogen or C1-C5alkyl and R3 is CF3 or CF2H, by a) reaction of a compound of formula II wherein R1 and R2 are as defined for formula I, with at least one reducing agent to form a compound of formula III wherein R1 and R2 are as defined for formula I, and b) reaction of that compound with at least one reducing agent to form a compound of formula IV wherein R1 and R2 are as defined for formula I, and (c) reaction of that compound with a compound of formula V wherein Q is chlorine, fluorine, bromine, iodine, hydroxy or C1-C6alkoxy and R3 is as defined for formula I, to form the compound of formula I; and to novel intermediates for use in that process.

Abstract: The present invention relates to a method for detecting the presence of a fungicide on a seed. In particular, the method according to the invention may be used to ensure that sufficient quantities of the fungicide or insecticide are present on the seed. In a particular embodiment the fungicide detected is thiabendazole.

Abstract: A display is provided for switching between a narrow or private viewing mode and a wide or public viewing mode. The display comprises a display device which is controlled to provide display of a desired image or sequence of images. This is associated with a liquid crystal device having at least one liquid crystal layer whose molecules are switchable between a first state providing a first angular viewing range and a second state providing a second angular viewing range which is within and smaller than the first angular viewing range. With the molecules in the second state, the device at least partially blocks light propagating towards part of the first angular viewing range outside the second angular viewing range. The or each liquid crystal layer is in contact with at least one alignment surface, the or each of which comprises a uniform non-patterned alignment surface.

Abstract: An illumination system (32) is provided for producing output light having a variable angular illumination range for illuminating a display panel (31) in a display device (30). The illumination system (32) comprises first and second light sources (34 and 36) and is operable selectively in a first mode in which the output light comprises light derived from the first light source (34) with substantially no light derived from the second light source (36), and in a second mode in which the output light comprises light derived from at least the second light source (36). The output light derived from the first light source (34) has a first angular illumination range and the output light derived from the second light source (36) has a second angular illumination range wider than the first angular illumination range. The first mode can be used as a private mode and the second mode can be used as a public mode.

Abstract: A display is provided for switching between a narrow or private viewing mode and a wide or public viewing mode. The display comprises a display device which is controlled to provide display of a desired image or sequence of images. This is associated with a liquid crystal device having at least one liquid crystal layer whose molecules are switchable between a first state providing a first angular viewing range and a second state providing a second angular viewing range which is within and smaller than the first angular viewing range. With the molecules in the second state, the device at least partially blocks light propagating towards part of the first angular viewing range outside the second angular viewing range. The or each liquid crystal layer is in contact with at least one alignment surface, the or each of which comprises a uniform non-patterned alignment surface.

Abstract: A liquid crystal display element is formed by providing a liquid crystal layer made of ferroelectric liquid crystal material between electrode substrates. One of the electrode substrate is composed of a substrate, electrodes, an insulating film, and an alignment film, while the other substrate is composed of a substrate, electrodes, an insulating film, and an alignment plate. The alignment film is formed by mixing a substance with ionic bond in an alignment film material and thereafter applying the mixture on the paired substrates on each of which the electrodes and the insulating film are provided. With this arrangement, ions are eluted from the alignment films thus formed into the liquid crystal layer, thereby becoming dispersed therethrough homogeneously. This remarkably reduces influences of display history, and half-tone display with excellent response characteristics can be realized, being not affected by display history.

Abstract: A method of addressing a liquid crystal device having a plurality of scanning electrodes and a plurality of data electrodes defining a plurality of pixels at the intersections between at least one of the plurality of scanning electrodes and at least one of the plurality of data electrodes, the method comprising applying one frame of a scanning signal to one of the plurality of scanning electrodes, applying a data signal to at least one of the plurality of data electrodes, one frame of the scanning signal comprising n strobe portions, where n is an integer greater than 1, for co-operation with the at least one data signal to address one of the plurality of pixels, and at least one blanking portion, the number of blanking portions not exceeding (n−1).

Abstract: A liquid crystal device is addressed in a multiplexed manner by a scanning signal applied in turn to a first set of electrodes together with data signals applied to a second set of electrodes. The first and second sets of electrodes define a plurality of pixels. The pattern to be exhibited by the device determines the waveform applied to the second set of electrodes which can vary between extremes of frequency. This has adverse effects on device performance, particularly with regard to contrast. To ameliorate the problem a low frequency signal is added to the scanning signal which incorporates a known strobe pulse. This low frequency signal reduces the effect on the pixels of the extremes of data signal frequency.

Abstract: Reduction of ionic memory effect in ferroelectric liquid crystal material. A method of reducing the effects of ionic memory in a ferroelectric liquid crystal (FLC) material to which a switching pulse is applied comprises the steps of: a) adding an ionic dopant to the FLC material, the ionic dopant providing ions having a fast response to an applied electric field; and b) following said switching pulse by a first pulse of opposite polarity to said switching pulse, in such a way that said first pulse reduces any ionic reversal field created by said switching pulse, but does not destabilize the state to which the FLC material is switched by said switching pulse.

Abstract: A light modulating device comprises a plurality of data electrodes, a plurality of strobe electrodes, pixels at the intersections of the strobe and data electrodes, and addressing means for supplying data signals to the data electrodes in successive data selection periods and for supplying strobe signals to the strobe electrodes to set the transmission levels of the pixels in dependence on the data signals supplied to the pixels during each data selection period. Each pixel comprises a pair of subelements, and the addressing means is arranged to address the subelements of the pair by 1:3 spatial dither and to supply different strobe signals to each of the subelements during different bits of 1:1 spatial or temporal dither within the same data selection period. The transmission level of each subelement is determined by the data signal applied to the subelement in the data selection period in association with the strobe signal applied to the corresponding spatial or temporal dither bit.

Abstract: Given a natural number “n”, then, in the first frame of continuous two frames, strobe pulses of opposite polarities are applied respectively to a scanning electrode L2n−1 in a (2n−1)'th line and a scanning electrode L2n in a 2n'th line during a selection period. In the second frame, strobe pulses of opposite polarities are applied respectively to the scanning electrode L2n in the 2n'th line and a scanning electrode L2n+1 in a (2n+1)'th line during a selection period.

Abstract: A ferroelectric liquid crystal device includes a layer of ferroelectric liquid crystal material contained between a pair of substrates, a first plurality of electrodes and a second plurality of electrodes defining a plurality of addressable liquid crystal pixels. A driving arrangement is provided for applying a first signal (Strobe) in succession to the first plurality of electrodes and for applying a plurality of second signals (Data) simultaneously to the second plurality of electrodes. The plurality of second signals are arranged to include non-rectangular wave signals which have a lower harmonic content than a rectangular wave. Non-uniform heating of the device as a result of the application of the second signals (Data) is reduced with consequent improvement in device performance.

Abstract: A spatial light modulator, for instance of the diffractive liquid crystal type, comprises an addressing circuit and a plurality of pixels. Each of the pixels has a plurality of first elongate electrodes and a plurality of second elongate electrodes interdigitated with the first electrodes. The first electrodes are connected to the addressing circuit whereas the second electrodes are electrically floating.

Abstract: A ferroelectric liquid crystal display comprises data electrodes and strobe electrodes which are connected to data and signal generators. The strobe signal generator supplies strobe signals sequentially to groups of more than one strobe electrode. For instance, the strobe electrodes may be strobed in pairs with the strobe signals being supplied simultaneously to the electrodes of each pair. The data signal generator supplies any of a plurality of different data signals to each of the data electrodes in synchronism with the strobe signals. The data signals are such that all combinations of optical states for the pixels which are connected to the same data electrode and which are strobed simultaneously can be achieved.

Abstract: A ferroelectric liquid crystal display comprises an addressable matrix of pixels 7 and addressing circuitry comprising a data signal generator 14 for applying data signals to column electrode tracks 4.sub.1, 4.sub.2. . . . . 4.sub.n and a strobe signal generator 15 for applying strobe signals to row electrode tracks 5.sub.1, 5.sub.2. . . . . 5.sub.m in order to selectively switch the pixels 7. In order to provide a large number of well defined grey levels, the addressing circuitry includes spatial and/or temporal dither control circuits for addressing separately addressable subpixels of each pixel 7 with different combinations of spatial dither signals and/or for addressing at least part of each pixel with different combinations of temporal dither signals applied to separately addressable temporal bits corresponding to subframes of different periods to produce a plurality of different transmission levels.

Abstract: A diffractive liquid crystal device includes a bistable liquid crystal arranged as pixels with each pixel being addressed by a strobe electrode and a pair of interdigitated data electrodes. A strobe generator supplies an initial blanking pulse to each of the strobe electrodes and then supplies strobe pulses in sequence to the strobe electrodes for at least several frames without any more blanking pulses. A data signal generator supplies data signals to the pairs of data electrodes which switch each pixel to a diffractive or non-diffractive state irrespective of its previous state. In particular, the strobe signals comprise pulses of opposite direction in consecutive frames. To select the non-diffractive pixel state, switching signals are applied to both the first and second electrodes during each frame.

Abstract: A spatial light modulator includes at least three picture elements, each of which includes a plurality of first elongate electrodes which are connected together and a plurality of second elongate electrodes which are connected together and which are interdigitated with the first electrodes. The first electrodes of a second of the picture elements are connected to the second electrodes of a first of the picture elements and the second electrodes of the second picture element are connected to the first electrodes of a third of the picture elements.

Abstract: A display such as a ferroelectric liquid crystal display includes a matrix of pixels, for instance formed at the intersections of data electrodes and strobe electrodes. In order to address an intermediate grey level, each pixel is switched from the normally black mode to the grey level in odd frames and from the normally white mode to the grey level in even frames. Variations in the grey levels, for instance caused by temperature variations, act in opposite directions so that the average grey level over time of the pixel varies relatively little.