Nec Corporation

Mitsubishi Paper Mills Limited

Nec Microwave Tube, Ltd.

Nec Corportion

Matsubishi Paper Mills Ltd.

Hideo Makishima

Hironori Imura

Keizo Yamada

Toshihiko Matsushita

Yoshinori Tomihari

Shunji Tsuida

Sadao Morishita

Masaaki Takahashi

Akihiko Okamoto

Hisashi Takemura

Toshihide Kuriyama

Kenji Hyodo

Hideaki Senoh

Yoshiaki Yanai

Haruyoshi Funae

Megumi Ikeda

Sadao Kinugasa

Electron tube device mounted with a cold cathode and a method of impressing voltages on electrodes of the electron tube device

A method and device are provided for preventing deterioration of a cold cathode in an electron tube device that utilizes the cold cathode as an electron source. In accordance with the expression defining the beam current of the electron tube device, Ib<P&mgr;&times;Va , where P&mgr; represents the perveance of an electron gun and Va represents a voltage impressed upon an accelerating electrode, the electric potential of the accelerating electrode or an adjacent electrode is maintained at the highest level of all electrodes in the electron tube at all times.

There is provided a field emission thin film cold cathode including a substrate, an electron-emission layer formed on the substrate and having a spherical surface or a curved surface approximated to a spherical surface recessed into the substrate, a first electrode disposed about the electron-emission layer and having a greater height from the substrate than the electron-emission layer, an electrically insulating layer formed on the first electrode, and a second electrode formed on the electrically insulating layer. The electron-emission layer may be made of monocrystalline diamond, polycrystalline diamond or amorphous diamond. The above-mentioned field emission thin film cold cathode provides an electron source which makes it no longer necessary to fabricate a micro-structured device, can be fabricated without a lithography apparatus having a high accuracy, and has a small current modulating voltage.

Field emission device having spherically curved electron emission layer

In a method of operating an electron tube including a plurality of emitters formed on a substrate and having sharp tips, gate electrodes surrounding the plurality of emitters, and a peripheral electrode surrounding an electron emission region constituted by the plurality of emitters and the gate electrodes and insulated from the plurality of emitters and the gate electrodes, the voltage applied to the peripheral electrode is set to be lower than the voltage applied to the gate electrode.

Method of operating electron tube

A field-emission cathode comprises a substrate having a conductive surface, a gate electrode and a focusing electrode overlying the substrate with insulation layers interposed therebetween, a plurality of cavities formed by penetrating the gate electrode, focusing electrode and insulation layers, and an emitter formed in each of the cavities on the substrate for emission of an electron beam. The emitter has tip located at a level between the gate electrode and the focusing electrode, which receive therebetween a signal for modulating the electron beam at a high frequency.

Field-emission cold-cathode electron gun having emitter tips between the

In a field emission cathode type electron gun, a plurality of cathode segments and a plurality of gate control circuits are provided. Each of the gate control circuits is connected to one of the cathode segments. Each of the cathode segments includes a cathode electrode, a gate electrode, an insulating layer therebetween, and a plurality of cone-shaped emitters formed within openings perforated in the gate electrode and the insulating layer. Each of the gate control circuits detects a current flowing through one of the cathode segments and controls a voltage of the gate electrode of the respective cathode segments in accordance with the detected current, so that the detected current is brought close to a definite value.

Field emission cathode type electron gun with individually-controlled

There is provided a cold cathode including a substrate, a plurality of electron emitting electrodes formed on the substrate, a first insulating layer formed on the substrate and formed with a plurality of first cavities in which the electron emitting electrodes are disposed, a gate electrode formed on the first insulating layer and formed with a plurality of first openings which are in communication with the first cavities, a second insulating layer formed on the gate electrode and formed with a plurality of second cavities which are in communication with the first openings, and a focusing electrode formed on the second insulating layer and formed with a plurality of second openings which are in communication with the second cavities. At least one of central axes of the second openings and central axes of the first openings is eccentric with central axes of the electron emitting electrodes. Eccentricity between at least one of the central axes of the second openings and the central axes of the first openings, and the central axes of the electron emitting electrodes is oriented outwardly, and a degree of the eccentricity is set greater at a location more remote from a centrally located electron emitting electrode.

Apparatus and method for light emitting and cold cathode used therefor

A field-emission cold cathode has a conductive cold-cathode substrate on which a plurality of conical emitters and a base insulator layer are formed. A ring-shaped gate electrode, a plate-shaped inner electrode, and a ring-shaped outer electrode are formed on the base insulator layer with the ring-shaped gate electrode disposed between the plate-shaped inner electrode and the ring-shaped outer electrode. A voltage supplying unit supplies the ring-shaped gate electrode, the plate-shaped inner electrode, and the ring-shaped outer electrode with a gate voltage, an inner electrode voltage, and an outer electrode voltage, each referenced to a substrate potential of the conductive cold-cathode substrate, wherein the gate voltage is higher than each of the inner electrode voltage and the outer electrode voltage.

Field-emission cathode capable of forming an electron beam having a high

Concave portions are formed, in a matrix fashion, in a substrate formed of metal or semiconductor. An electron emission layer made of material having small work function such as a diamond thin film is formed on the bottom portion of the concave portion. A protruding portion of the substrate serves as a beam formation electrode. Divergence of electrons can be suppressed with the beam formation electrode. A gate electrode for drawing out the electrons is formed above the beam formation electrode.

Electron device employing field-emission cathode

The invention forms on a substrate an electron emission area composed of at least a single micro cold cathode which is composed of an emitter and a gate electrode, arranges plural focusing electrodes surrounding this electron emission area in the periphery of the electron emission area, and connects with each other the focusing electrodes facing each other around the electron emission area. An electron beam having a vertically long spot near the cathode is formed by making more intense the horizontal focusing when the electron beam is scanning the peripheral part of the screen on the basis of a horizontal and a vertical synchronizing signal. Thus the invention can correct distortion of the electron beam caused by deflection and can achieve and excellent resolution all over the display screen, and furthermore, can compose a cathode ray tube using this cold cathode as an electron source.

Cold cathode and cathode ray tube using the cold cathode

In a field emission cold cathode composed of a plurality of micro cold cathodes, the diameter of a plurality of openings formed in a gate electrode is large at a central region of an electron emission zone but small at a peripheral region of the electron emission zone, or the thickness of the gate electrode is small at the central region of the electron emission zone but large at the peripheral region of the electron emission zone. Alternatively, the thickness of an insulator layer is small at the central region of the electron emission zone but large at the peripheral region of the electron emission zone. Or, a resistance layer is provided between a substrate and a plurality of electron emission electrodes, and resistivity of the resistance layer is small at the central region of the electron emission zone but large at the peripheral region of the electron emission zone.

Field emission cold cathode having micro electrodes of different

Tips of emitters are protruded over a control electrode in a field emission cathode. The cathode is a part of an input cavity, and an anode facing the cathode is also a part of the input cavity. A voltage which is in the vicinity of a threshold value or less than the threshold value is applied across the control electrode and the emitters, so that an emission current is modulated in density by a RF input signal.

Cold cathode density-modulated type electron gun and microwave tube

A field emission cold cathode element having a conducting substrate, a dielectric layer which is on the substrate and has holes, emitter electrodes each of which have a sharp-pointed tip and stand on the substrate in the respective holes in the dielectric layer, and a gate electrode layer which is on the dielectric layer and has apertures right above the respective holes in the dielectric layer. The tip of each emitter electrode is near or in the aperture in the gate electrode layer, and the emission current depends on the position of the emitter tip relative to the gate electrode. The dielectric layer and the gate electrode layer are largely removed so as to remain only in limited first regions which are around the holes for the respective emitter electrodes and limited second regions each of which connects one of the first regions to another. The partial removal of the dielectric and gate electrode layers is for reducing interlayer stresses induced by temperature changes. In the first regions the gate electrode layer is made thicker than in the second regions to compensate for inevitable variations in the emitter electrode heights without augmenting the interlayer stresses.

Field emission cold cathode element having exposed substrate

A field emission cold cathode element having a conducting substrate, a dielectric layer which is on the substrate and has holes, emitter electrodes which have a sharp-pointed tip and stand on the substrate in the respective holes in the dielectric layer, and a gate electrode which is on the dielectric layer and has apertures right above the respective holes in the dielectric layer. The tip of each emitter electrode is near or in the aperture in the gate electrode layer. The dielectric layer is largely removed so as to remain only in limited regions around the holes for the respective emitter electrodes, and a gate electrode layer is formed with, in addition to the apertures for the emitter electrodes, a number of holes in regions where the substrate surface is exposed by removal of the dielectric layer. The partial removal of the dielectric and gate electrode layers has the effect of reducing interlayer stresses induced by temperature changes, so that the gate electrode layer can be made desirably thick.

Growing community of inventors

Tokyo, Japan

Hideo Makishima