Nec Corporation

Kazuo Konuma

Akihiko Okamoto

Fuminori Ito

Yoshinori Tomihari

Yuko Okada

A fabrication method for an emitter includes the steps of forming on a glass substrate a CNT film which contains a plurality of carbon nanotubes (CNTs) and constitutes an emitter electrode, forming a gate electrode via an insulating film on the CNT film, forming a plurality of gate openings in the gate electrode and the insulating film, and aligning upright the CNTs in the gate opening. The upright alignment generates a stable uniform emission current and provides excellent emission characteristics.

CNT film and field-emission cold cathode comprising the same

A method for driving an electric-field electron emission apparatus without degrading the electron emission characteristics is provided. The method can drive the electric-field electron emission apparatus without degrading the electron emission characteristics by allowing application of the electric field only when the second derivative of the captured electron current density exceeds a certain value.

Driving method for electric-field electron emission apparatus

A field emission display includes a cathode panel having an array of electron source units for emitting electrons and a fluorescent panel distanced by a vacuum inter-space from the cathode panel. A cathode panel driver circuit is connected to the field emission display panel for controlling electron emissions from the electron source units. A fluorescent voltage supplying device is connected to the fluorescent panel for supplying a fluorescent voltage to the fluorescent panel. A current measuring device is connected to the fluorescent voltage supplying device for measuring a current value of the fluorescent voltage supplying device. A memory connected to the current measuring device receives a measured current value from the current measuring device and stores the measured current value. A correcting device is connected to the memory for receiving the measured current value for correcting control signals on the basis of the measured current value. The correcting device is also connected to the cathode panel driver circuit for transmitting the corrected control signals to the cathode panel driver circuit.

Field emission display and method of driving the same

Electron emission device with picture element array

A method of driving a cold cathode element, includes (a) providing a plurality of cold cathodes; (b) deflecting a plurality of electron beams respectively emitted from the plurality of cold cathodes; (c) providing at least one control electrode for at least one of the plurality of cold cathodes, wherein an electric field above the control electrode is changed when a voltage is applied to the control electrode; and (d) controlling the voltage applied to the control electrode such that the plurality of electron beams are concentrated on a fluorescent surface.

Cold cathode display device and driving method

The present invention relates to a method of manufacturing a field emission cold cathode device, having a field emission cold cathode element which comprises a plurality of emitters formed on a substrate and each in the shape of a sharply pointed cone, and a gate electrode provided with an opening section to let electrons emit from the respective apexes of said group of emitters and set in the vicinity above said group of emitters, wherein a positive voltage with respect to the emitters is applied to said gate electrode and thereby an electron beam is emitted from the group of emitters; a lens electrode making the electron beam which is emitted from said group of emitters converge; and a target on which the electron beam made to converge by said lens electrode irradiates; wherein the area of the region occupied by the group of emitters is set at the optimum size using specific equations. According to the present invention, it is possible to provide a field emission cold cathode device capable to accomplish excellent emission and convergence of the electron beam without making trial and error in experiments but with designing.

Field emission cold cathode device and manufacturing method thereof

There is provided a field emitter capable of efficiently maintaining the temperature of an emission point at a constant temperature. Electrons are supplied to the emission point for emitting electrons, through both two routes which are composed of a first cathode in contact with a first cathode base conductor, and a second cathode, respectively. The first cathode and the second cathode are contacted at the emission point. The first cathode and the second cathode are insulated from each other by using a conical insulator layer. A gate metal film is provided for applying a strong electric field to the emission point. A gate metal film, the second cathode and the first cathode base conductor are connected to a gate applying wiring conductor, a second cathode wiring conductor and a first cathode wiring conductor, respectively.

Field emitter

A field emission device is provided, which is able to prevent the inclination of emission direction of electrons. An insulating layer is formed on a first main surface of a substrate. A conductive layer with a gate electrode part and an interconnection part is selectively formed on the insulating layer. A second conductive layer is formed on the second main surface of the substrate. The first part has a window to expose the insulating layer. The insulating layer has a hole to expose the first main surface of the substrate. The hole is located just below the window of the conductive layer. A conical cathode is formed on the exposed first main surface of the substrate in the bole. The central axis of the cathode, which penetrates the tip of the cathode, is tilted with respect to a normal of the second conductive layer toward an opposite side to the interconnection part of the conductive layer. The direction of the emitted electrons is approximately parallel to the normal of the second conductive layer.

Field emission device with tilted cathodes

A getter in a tube body is heated in an exhaust process of a cathode ray tube, and during the time gas is emitted due to the heating of the getter, electrons are emitted from the cathode. Then the exhaust tube of the tube body is sealed to maintain a high vacuum by utilizing the absorbing function of the getter.

Method of cleaning the cathode of a cathode ray tube and a method for

A field emitter array comprises a plurality of cathode electrodes and an anode electrode disposed opposite to the plurality of cathode electrodes. And the anode electrode is provided with a plurality of protrusions having a cap material disposed on the tip of each protrusion. A voltage below a designated value is applied between a gate electrode and the cathode electrodes, and electrons are released only from a cathode electrode with a low emission start voltage. When the electrons are emitted to the cap material provided on the protrusions, the cap material is sputtering-evaporated and is affixed to the cathode electrode. Then a cap is disposed on the each of the cathode electrodes. Then, the emission properties between each cathode electrode are consequently rendered uniform, thereby increasing the emission start voltage and maximum applied voltage of the overall field emitter array.

Field emitter array with cap material on anode electrode

A field emission device is configured so as to suppress any deviation of the central axis of the distribution of emitted electrons from a conical cathode, with no electrode in addition to the gate electrode. A conductive layer is disposed over an insulating layer and has an electron emission window disposed over the conical cathode. Plural curved slits are formed in the conductive layer so as to expose the insulating layer and are arranged along a circle which is concentric with the tip of the conical cathode. The gate electrode is formed by the portion of conductive layer between the electron emission window and the curved slits. The portion of the conductive layer outside of the curved slits serves to distribute an applied potential to the gate electrodes of plural field emission devices arranged in a matrix. The portions of the conductive layer disposed between the curved slits serve to connect the gate electrode to the outer portion of the conductive layer. By selection of the physical geometry of the gate electrode, the field emission window, and the curved slits, and/or by selection of the relative doping concentrations of the gate electrode and the portions of the conductive layer disposed between the curved slits, any deviation in the emission direction of the electrons is automatically compensated for by a deviation in the voltage dropped by a portion of the gate electrode into which a disproportionate amount of electrons have been emitted.

Field emission device having configuration for correcting deviation of

A solid-state infrared sensor using a Schottky barrier diode. The sensor has a first layer of a semiconductor of a first conductivity type and a second layer of a metal or a metal silicide and the first and second layer are joined to each other to form the Schottky barrier diode. Further, the sensor includes a third layer disposed in the depletion layer formed in the first layer out of contact with the Schottky junction interface. The third layer contains an impurity which is introduced for positioning an effective barrier formed in the depletion layer under an image force, closely to the junction interface. Intensity of an infrared radiation is detected using a multiple reflection effect of hot carriers. According to the infrared sensor, since the position of the effective barrier generated by an influence of a image force is close to the Schottky junction, the attenuation of the energy of the hot carriers is suppressed and the injection yield of the hot carriers passing through the Schottky barrier is increased.

Schottky barrier infrared sensor

The present invention provides an image sensor of the charge transfer type which employs solid-state image pickup devices and a method of driving the image sensor. Gate electrodes to which pulse voltages can be applied and which preferably are transparent are disposed at a period distance shorter than the spatial arrangement period distance of pixels on light receiving faces of light receiving elements formed from photodiodes or like elements. Upon imaging using the image sensor, the combination of voltage to be applied to the gate electrodes is varied to vary sampling points of the light receiving faces in accordance with an environment or an object of use of the image sensor so that a fixed resolution and a fixed sensitivity can be obtained.

Image sensor and driving method for the same

A light receiving device includes, in addition to a photodiode and a reset element, a comparator formed by a first and a second MOS transistor and a counter. The comparator compares an output potential of the photodiode applied to a gate electrode of the first MOS transistor with a threshold potential externally applied to a gate electrode of the second MOS transistor. The counter counts a time duration from a point of time when the photodiode is reset by the switching element to a point of time at which the output potential of the photodiode exceeds the threshold potential, and outputs the time duration in a numeral value corresponding to the quantity of light incident on the photodiode. The required light sensitivity can be maintained even when the quantity of light is either large or small. Also, non-destructive reading can be carried out.

Device for receiving light used in CCD image sensor or the like

Photo-sensing elements are arranged in a form of a matrix, with photo-sensing characteristics substantially equal with each other in a row direction, but different therebetween in a column direction. Vertical charge transfer circuits receive charge signals in parallel from the photo-sensing elements, and transfer them as serial data therealong, respectively, to a horizontal CCD, which receives respective lowermost signals of the serial data from the vertical charge transfer circuits and transfers them as a serial data therealong, in which associated signals are substantially free of siginificant irregularities therebetween, so that the horizontal charge transfer circuit has an improved apparent charge transfer efficiency and an optimized drive amplitude, in addition to that a signal amplification in a data processor may be achieved with an optimized gain.

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Tokyo, Japan

Kazuo Konuma