Abstract: An analogue display includes an electrical sensitive medium enclosed between two sets of electrodes. The two sets of electrodes are registered and overlap to provide background and one or more shaped index characters, each at a plurality of selectable positions. Voltage signals are applied to the electrodes so that the medium is held in an OFF state in the region between selected electrodes, while simultaneously voltage signals are applied so that in other regions of the medium, the medium is in an ON state. The medium may be of liquid crystal, electroluminescent or gaseous material. One set of electrodes may have a meander configuration, the other set a segmented configuration. The index character or characters may be displayed at one, two or three positions, each character being of different shape, for meter or timepiece applications. The voltage signals applied may be binary coded and in preference pseudo-random sequence binary codes.

Abstract: A waveform display including an opto electric display having m X electrodes and n Y electrodes arranged in a m x n element matrix. A series of m different reference binary codes are applied simultaneously one to each of the X electrodes. A waveform to be displayed is sampled and binary numbers representative of the amplitude of each sample are produced. These sample binary numbers are each converted into one of the reference binary codes for applications to the Y electrodes; the code so produced being related to both the amplitude value and the order of reference codes on the X electrodes. As a result of the simultaneous application of appropriate binary codes to each X, Y electrode, unselected X-Y intersections receive an rms voltage above a display threshold while selected X-Y intersections receive a zero voltage and collectively display the waveform.The opto-electric display may be a liquid crystal display or an electro luminescent display.

Abstract: A liquid crystal device includes a liquid crystal cell capable of rotating plane polarized light, one or more layers of a birefringent material, and polarizers. Application of voltages to the liquid crystal cell changes the angular rotation of light passing through the device and hence changes the observed color. The actual color observed is dependent on the birefringent film, its thickness and its relative angular orientation to the polarized light.

Abstract: A matrix display including an electro-optic display having a layer of display material contained between two spaced substrates carrying m X and n Y electrodes arranged in an array to provide an m x n element matrix. A first series of m different coded waveforms are applied one to each X electrodes simultaneously and a second series of coded waveforms are applied simultaneously to the Y electrode. This second series of waveforms has codes different from one another and from the first series of waveforms. Additionally each code in the second series is related both to the codes on the X electrodes and to the information required to be displayed at each element along its associated Y electrode. As a result selected elements receive an r.m.s. voltage below a display effect threshold while others receive an r.m.s. voltage above threshold to collectively display the required information. The codes may be two or more level codes. Two level codes, binary codes, may be pseudo random series or orderly binary codes.

Abstract: In order to provide a liquid crystal display device having enhanced contrast, pleochroic and fluorescent materials are incorporated in one or more components of the device. The materials are incorporated in balanced proportion and have absorbtion and emission spectra, respectively, that are complementary. Light incident on the display is thus converted so that light reaching the eye from the bright state regions of the display is neutral grey in contrast to the light from the dark state regions, which is strongly attenuated and may be strongly colored.

Abstract: An electronic analogue waveform display comprises a liquid crystal cell having x, y electrodes whereby the cell is addressed in a matrix manner by applying electric potentials of about zero at required x, y intersections and above a threshold voltage at all other intersections. A waveform to be displayed is divided into a series of amplitude samples and electrical potentials representative of these samples are applied to the x, y electrodes while a series of electric potentials are applied to x electrodes. Rectangular or sinusoidal waveforms may be applied to the x, y electrodes. Various circuits for producing a display are disclosed.