A capacitive arrangement which, in some instances, can be used in combinan with one or more resistive elements or other circuit elements to form a distributed circuit, wherein a slab of anisotropic single crystal, such as barium titanate, is used as a substrate upon whose major surfaces the circuit electrodes or elements are mounted. When electrodes are disposed on opposite surfaces of the slab between which an electric field exists and if the crystal slab is mounted so that the C axis is perpen...

Structure and apparatus located on a satellite which control the environm of a crystal oscillator for the purpose of attaining extreme frequency stability and reducing the problems of pre-flight testing and adjusting. The oscillator is located in an evacuated chamber together with heat shields and ovens.

Apparatus for the formation of single crystal articles by directionally solidified casting techniques which substantially eliminates the formation of heterogeneous discontinuities in the casting.

A silane derivative is chemisorbed on the interior surfaces of the substrates of a liquid crystal display to eliminate cloudiness of the display and to increase contrast.

A crystal controlled oscillator is frequency sensitive to variations in crystal load capacitance in circuit with the crystal, to variations in temperature and to operation over extended periods of time. A variable capacitor is provided in circuit with the crystal so as to correct for the crystal frequency drifts due to changes in operation of the crystal over extended periods of time. A separate fixed capacitor is connected in series with the crystal and in circuit with the variable capacitor to...

Front and rear substrates sandwich a liquid crystal material therebetween. The substrates are transparent, and each substrate has a layer of a conductive material on the inside surface thereof. A thin opening or line divides the conductive material layers into segments, at least one of the segments of each layer defining an image, the images of the two layers being different. A layer of dielectric material covers one of the conductive layers and has an opening therethrough defining a third image...

The frequency of a square wave transistor multivibrator oscillator is determined by a high-gain AC coupled quartz crystal feedback loop. Oscillator startup is provided by a DC coupled RC network feedback path which provides only sufficient gain to barely sustain oscillations. When power is turned on, the first-stage transistor is slowly biased through its linear region. The RC network thus provides a sinusoidal wave until energy at the resonant frequency of the crystal is produced, whereupon the...

A nematic liquid crystal material which assumes a homeotropic texture is provided by dissolving an additive material having the formula RR.sub.3 'N.sup.+ X.sup.- wherein R is an alkyl radical having 10 to 24 carbon atoms, R' is a methyl or ethyl radical, and X.sup.- is an anion derived from a simple acid, in a nematic material. A typical example of the additive is hexadecyltrimethylammonium bromide. The homeotropic texture provided by this composition, when placed between two conducting transpar...

The liquid crystal device comprises a liquid crystal layer, a thin photoconductor layer, and a thin insulator layer sandwiched between the transparent supporting covers having a transparent electrically-conductive layer thereon. The photoconductor layer is cadmium sulphide (CdS) and the insulator layer is zinc sulphide (ZnS).

An improved liquid crystal display is disclosed in which a multilevel gray scale is provided by stacking a plurality of conventional liquid crystal display devices and addressing the respective display devices in selected combinations. Successive display devices in the stack are of different thicknesses or of different material composition, such that with like magnitude signals applied thereto, each display scatters light by a different predetermined amount. A single addressing circuit is employ...