Abstract:
A flat screen field emission cathode is disclosed including microtips individually protected by means of a series electrical coupling with a dipole consisting of a depletion mode field effect transistor. The current-voltage characteristic of such a dipole is not linear. These dipoles can be obtained such that the protection threshold and current emission level, and therefore the brilliance of the screen, can be altered globally (on all tips at once) solely by acting on the biasing of the substrate common to these dipoles, or groups of dipoles.
Abstract:
A method, device and system for utilizing a pixelized ungated linear array of field emitters and an integrated electrode-media surface to either detect the presence of charge on the surface in a given two-dimensional pattern, or to deposit charge on the surface in a desired two-dimensional pattern. The methods, devices and systems disclosed are particularly useful in the arts of printing, scanning and copying. In one embodiment designed for printing, a pixelized surface may be utilized to receive a charge pattern from the ungated linear field emitter array. In one embodiment designed for scanning, a pixelized transfer sheet may be utilized to transfer a two-dimensional charge pattern from a photostatic surface thereto for sensing and detection by the ungated linear field emitter array.
Abstract:
An imaging apparatus for providing an image from a display to an observer, comprising: a display generating an optical output, an imaging surface member constructed and arranged for viewing by said observer, and a scanning mirror/lens assembly optically interposed between the display and the imaging surface member, and constructed and arranged to motively repetitively scan the display, generate a scanned image, and transmit the scanned image to the imaging surface member, for viewing of the scanned image. Various field emitter display designs and subassemblies are described, which may be usefully employed in such imaging apparatus.
Abstract:
A field emission cathode capable of preventing an increase in emission current discharged from conical emitters due to a variation in environmental temperature. The field emission cathode includes a resistive layer structure, which is constructed of two resistive layers different in temperature charactertistics. Such construction substantially prevents a variation in resistance of the whole resistive layer strcuture due to an increase in environmental temperature.
Abstract:
A field emission display includes electrostatic discharge protection circuits coupled to an emitter substrate and an extraction grid. In the preferred embodiment, the electrostatic discharge circuit includes diodes reverse biased between grid sections and a first reference potential or between row lines and a second reference potential. The diodes provide a current path to discharge static voltage and thereby prevent a high voltage differential from being maintained between the emitter sets and the extraction grids. The diodes thereby prevent the emitter sets from emitting electrons at a high rate that may damage or destroy the emitter sets. In one embodiment, the diodes are coupled directly between the grid sections and the row lines. In one embodiment, the diodes are formed in an insulative layer carrying the grid sections. In another embodiment, the diodes are integrated into the emitter substrate.
Abstract:
A field emitter device formed by a veil process wherein a protective layer comprising a release layer is deposited on the gate electrode layer for the device, with the protective layer overlying the circumscribing peripheral edge of the opening of the gate electrode layer, to protect the edge of the gate electrode layer during etching of the field emitter cavity in the dielectric material layer on a substrate, and during the formation of a field emitter element in the cavity by depositing a field emitter material through the opening. The protective layer is readily removed subsequent to completion of the cavity etching and emitter formation steps, to yield the field emitter device. Also disclosed are various planarizing structures and methods, and current limiter compositions permitting high efficiency emission of electrons from the field emitter elements at low turn-on voltages.
Abstract:
A field emission display for reducing luminance unevenness by construction means. A plurality of stripe shaped cathode wirings 102 are formed in the cathode area 109 on a cathode substrate 101. Cut-through sections 108 are formed in each of the cathode wirings 102 and an island-like electrode 107 is formed within each cut-through section 108. A resistance layer 103 is formed on the cathode wiring 102, the cut-through section 108 and the island-like electrode 107. A plurality of emitter cones 106 are formed on the resistance layer 103 so as to provide a field emission array. The distance between the island-like electrode 107 and the cathode wiring 102 is changed depending on the position thereof in the cathode area 109 so as to correct deviation of the emission characteristic depending on the position. In the case of a full-color field emission display, white balance can be corrected by changing the distance depending on the luminous color of each dot.
Abstract:
A field emission cathode which is capable of increasing bond strength between emitters and a resitive layer and a method for manufacturing the same which is capable of facilitating manufacturing of the cathode. The field emission cathode includes a laminated board, which includes a substrate, and at least a cathode electrode layer, a resitive layer, an insulating layer and a gate electrode layer which are deposited in the form of a film on the substrate in order. The gate electrode layer and insulating layer are formed with through-holes so as to commonly extend through the gate electrode layer and insulating layer. The cathode also includes buffer layers made of an insulating material and formed on portions of the resistive layer exposed via the through-holes, as well as emitters arranged on the buffer layers, respectively, resulting in bond strength between the resistive layer and the emitters being increased.
Abstract:
The invention generally relates to the technical field of devices using the effect to emit electrons out of a solid into vacuum due to high electric field strength. Such devices are usually called field emission devices. The invention relates more specifically to the structure of a field emission device, to the method of fabricating a field emission device, and to the use of a multitude of field emission devices in the technical field of flat panel displays. The inventive structure of a field emission device (15) comprises an individual series resistor for each electron emitting tip (1), wherein the series resistor is formed by the tip (1) itself. The tip (1) comprises a body (9) of a first material with high resistivity and an at least partial coating (7) of a second material with low work function, wherein the body (9) of the first material forms the series resistor and the coating (7) of the second material provides for electron emission. The method for fabricating a field emission device (15) uses depositing and sacrificial layer etch back techniques to provide easy and precise control of tip height and shape and also easy and precise control of the tip-to-gate distance and geometry.
Abstract:
A field emission display includes a discrete storage capacitor coupled between a column line and a reference potential. The display also includes a discharge circuit coupled between a transmission line tap and the storage capacitor. The discharge circuit receives an image signal from the transmission line and transfers charge from the transmission line to the storage capacitor. In one embodiment, the discharge circuit includes a pair of opposed zener diodes. In response to a brief negative-going input pulse on the transmission line, the capacitor is discharged through the diodes. Then, the diodes recover and capacitor and column line are isolated from the tap. A selected line of an extraction grid is then activated to extract electrons from an emitter set coupled to the column line. The voltage differential between the extraction grid and the emitter set extracts electrons from the emitter set that are replaced by the capacitor. The capacitor has sufficient capacitance to supply electrons over an expected refresh interval of the column line. Therefore, the voltage of the capacitor remains substantially constant over the refresh interval. Because the capacitor can be charged quickly, the input pulse can be short relative to the refresh interval.