Abstract: A piezoelectric actuator includes a supporting member in which pressure chambers are formed, a vibration plate which is joined to a joining section of the supporting member, a piezoelectric layer formed on the vibration plate, and an FPC provided on the piezoelectric layer. A contact section of an electrode formed on the piezoelectric layer and a terminal section of the FPC are electrically connected via a bump formed on the terminal section. A recess is formed on an upper surface of the supporting member right below the bump. While joining the piezoelectric layer and a wire member, any damage of the piezoelectric layer and any poor connection do not occur.

Abstract: A piezoelectric element is provided that is equipped with a seed layer formed on a base substrate and a piezoelectric film formed on the seed layer. The seed layer is formed of a perovskite type piezoelectric material preferentially oriented to pseudo cubic (100). The piezoelectric film is formed of a relaxor material that has a perovskite type rhombohedral structure, and is preferentially oriented to pseudo cubic (100).

Abstract: A piezoelectric vibrating piece having a first and a second surface at an opposing side of the first surface is comprised of an piezoelectric piece having designated coefficient of thermal expansion; a first electrode film having bigger coefficient of thermal expansion than the designated coefficient of thermal expansion and formed on the first surface; and a second electrode film having smaller coefficient of thermal expansion than the designated coefficient of thermal expansion and formed on the second surface.

Abstract: Electroactive polymer transducers are disclosed. They are biased in a manner that provides for increased force and/or stroke output, thereby offering improved work potential and power output capacity. The biasing may offer additional or alternate functional advantage in terms of matching transducer performance with a given application such as a normally-closed valve. The improved biasing (including increased output biasing) may utilize negative spring rate biasing and/or a combination of negative or zero-rate biasing with positive rate biasing to achieve the desired ends.

Abstract: A thickness shear mode (TSM) resonator is described, comprising a diamond layer. The diamond layer is preferably a high quality diamond layer with at least 90% sp3 bonding or diamond bonding. A method for manufacturing such a resonator is also described. The thickness shear mode resonator according to embodiments described herein may advantageously be used in biosensor application and in electrochemistry applications.

Abstract: A mounting structure for a motor includes a tube and a stator. The tube includes at least an axial positioning block and at least a radial mounting block. The stator defines an axis hole for receiving a portion of the tube therein, and at least a positioning groove in an inner surface thereof. One of the stator and the tube is rotated from an unlock position, where the at least an axial positioning block is located just above the at least a positioning groove, to a locked position, where a bottom surface of the at least an axial positioning block abuts a top surface of the stator and the at least a radial mounting block engages with the inner surface of the stator.

Abstract: A motor includes a rotor portion including a shaft and a rotor magnet rotatable about a center axis, an armature arranged opposite to the rotor magnet to generate a torque therebetween, a circuit board arranged below the armature in an axial direction substantially parallel to the center axis and including a control circuit controlling rotation of the rotor portion, and a base portion including a bearing holder which supports the armature on its outer side surface and the shaft on its inner side surface via a bearing member. The armature is pressed against the bearing holder in the axial direction with an elastic member.

Abstract: An electric power generation system is disclosed. The electric power generation system includes: a string configured to be pulled; a bobbin configured to rotate when the string is unwound from the bobbin as the string is pulled; an electric power generator having a rotor wherein the rotor is mechanically coupled to the bobbin; and a retraction circuit, wherein the retraction circuit uses the electric power generator as a motor to retract the string.

Abstract: An electric power generation system is disclosed. The electric power generation system includes: a first string and a second string configured to be pulled; a first portion of a bobbin configured to rotate in a direction when the first string is unwound from the bobbin as the first string is pulled; a second portion of a bobbin configured to rotate in the direction when the second string is unwound from the bobbin as the second string is pulled; and an electric power generator having a rotor wherein the rotor is mechanically coupled to the bobbin. The pulling of the second string causes the first string to retract and the pulling of the first string causes the second string to retract.

Abstract: An electric power generation system is disclosed. The electric power generation system includes: an electric power generator having a rotor wherein the rotor is mechanically coupled to a shaft; and a case with a first chamber and a second chamber. The second chamber includes a primary mechanical turning source. The primary mechanical turning source can be removed to enable the attachment of a secondary mechanical turning source.

Abstract: A hard disk drive drawer includes a fixed casing mountable inside a computer housing, and a drawable carrier moveably and detachably receivable in the fixed casing. The fixed casing having two opposite lateral panels, each of which is provided with a track and a retaining portion located at the track adjacent to a free end of the track. The drawable carrier is elastically deformable for holding a hard disk drive therein. The drawable carrier has two sliding rails disposed at two opposite lateral sidewalls thereof and detachably, slidably and respectively coupled to the tracks, a handle at one side thereof, and two positioning portions engageable with the retaining portions of the fixed casing.

Abstract: An image forming apparatus including: a first body; a second body to pivot between a closed position and an open position in relation to the first body; a guide lever member to control a pivoting of the second body and having a first end connected to one of the first body and the second body, and a second end, opposite the first end; and a guide rail member including: a guide rail along which the second end of the guide lever member is slidably connected. The guide rail member includes a first pressing portion to constrain the second end of the guide lever member in the open position of the second body, and a second pressing portion to prevent the second body from abruptly closing while the second body is being closed.

Abstract: A cabinet facilitating storage, transport, and assembly, and its package method, are provided. The cabinet consists of 2 bounding-frame subassemblies, a door, a back-board, connecting-beams, and screws. The bounding-frame subassembly is constituted of a bounding-frame, and a panel, mounting-beams, device-mounting battens etc., which are mounted on the bounding-frame in advance. Each of the 4 corner ends inside 2 bounding-frame subassemblies is provided with an embedding head, which is inserted into and engaged with the connecting-beam. It is easy to assemble the cabinet at the spot, because the engaging structure of 2 bounding-frame subassemblies and the connecting-beams can be fixed with 8 screws so that the cabinet's frame can be assembled quickly. When packed, it is possible to put the door, the back-board, the connecting-beams, the screws etc., into the space S formed by 2 bounding-frame subassemblies.

Abstract: Our invention incorporates several methods or types of storage into one compact, aesthetically pleasing, easy to use unit.

Abstract: A cabinet includes a cabinet body, multiple drawers and a safety device. The drawers are mounted moveably in the cabinet body. The safety device is mounted in the cabinet body and has a control member and multiple hook members. The control member is mounted on the rear panel of the cabinet body and has a supporting base, a pivotal member and a resilient element. The pivotal member is mounted pivotally on the supporting base. The resilient element is connected to the supporting base and the pivotal member. The hook members are mounted respectively on the drawers and are aligned with the pivotal member. When a drawer is opened, the corresponding hook member pushes the pivotal member to pivot the pivotal member and stretch the resilient element and a hook flange on the pivotal member engages the hook members on other drawers to prevent other drawers from being opened.

Abstract: A drawer slide assembly includes an upper slide; an inner slide having a buffer unit located therein; at least two upper sliding guides being provided on top and bottom with first sliding bearings to bear against upper inner and lower inner surfaces of the upper slide and upper inner and upper outer surface of the inner slide, and on a lateral wall with second sliding bearings to bear against a lateral inner surface of the upper slide and a lateral upper outer surface of the inner slide, so that the upper slide and the inner slide are mutually slidably assembled to each other; and a mounting plate for holding the assembled upper slide and inner slide to a fixed place. With the sliding bearings so arranged, the drawer slide assembly provides a buffering effect to enable smooth and stable opening and closing of a drawer box.

Abstract: An ice supplier includes an ice maker configured to make ice, a case configured to store ice made by the ice maker, a sensing unit configured to sense a quantity of ice stored in the case, and a controller configured to control the ice maker according to a result of sensing from the sensing unit.

Abstract: An electric lamp with a holder on one side, particularly a high-pressure discharge lamp, comprising a vacuum-tight sealed inner vessel which is surrounded by a surrounding part, wherein one holder with electrical connections bears the inner vessel and the surrounding part. The lamp is characterized by the following features: a) the holder is comprised of a holder stone having a central opening and a surrounding collar in which the inner vessel is accommodated; b) the holder stone has an element for fixing the surrounding part, c) the surrounding part has a circular opening on the holder side, that has a given inner diameter ID, and has a radially outwardly protruding enlargement with a given outer diameter UB, which is used as a holding member on the holder stone, wherein the ratio UB:ID=1.25; d) the surrounding part is fixed to the holder stone by a cement-free mechanical holding mechanism.

Abstract: An apparatus of light source includes a cathode structure, an anode structure, a fluorescent layer, and a low-pressure gas layer. The fluorescent layer is located between the cathode structure and the anode structure. The low-pressure gas layer is filled between the cathode structure and the anode structure, and has the function of electric conduction. The low-pressure gas layer has an electron mean free path, allowing most of electrons to directly impact the fluorescent layer under an operation voltage.

Abstract: A field emission display device (FED) is disclosed. The FED disclosed herein includes: a upper substrate, an anode layer, a phosphor layer, a lower substrate, at least one cathode, at least one electron emitter, and an partition plate set located between the upper substrate and the lower substrate. The partition plate set includes at least one nonmetal dielectric plate having plural holes, at least one insulation layer, and at least one gate. The FED of the present invention can simplify the process and reduce the damage caused by the manufacturing process, effectively increase the number of the electrons bombarding the phosphor layer, and increase the brightness and contrast ratio of the pixels.

Abstract: The present invention relates to a field emission display device, especially to a field emission display device with a lower gate field emission structure. The field emission display device includes an upper substrate, a lower substrate, an anode layer, a plurality of gate layers, an insulation layer covering on the surface of the upper substrate and the gate layers, a plurality of cathode layers formed on the surface of the insulation layer, and a plurality of field emitter layers formed on the surface of the cathode layers. Moreover, the anode layer is formed on the surface of the upper substrate corresponding to the surface of the lower substrate. The gate layers are formed on the surface of the lower substrate corresponding to the surface of the upper substrate. The cathode layers are interlaced with the gate layers, but without conducting to the gate layers.

Abstract: A field emission lamp includes a transparent glass tube, a cathode, and an anode. The anode and cathode are both disposed in the transparent glass tube. The cathode includes an electron emission layer. The anode includes a carbon nanotube transparent conductive film formed on an inner wall of the transparent glass tube and a fluorescent layer formed on the carbon nanotube transparent conductive film. A method for fabricating the above-described field emission lamp, includes the steps of: (a) providing a transparent glass tube including at least one conductive wire, a carbon nanotube transparent conductive film and a fluorescent layer formed on the inner wall thereof; and (b) providing an anode electrode, a cathode electrode, a cathode emitter sealed by feedthroughs in the glass tube to achieve the field emission lamp.

Abstract: An image display apparatus of smaller beam deviation is provided by making smaller the absolute value of an angle formed by an initial velocity vector of an electron emitted from the first electron-emitting devices closest to a spacer 100 and a line parallel to the longitudinal direction of a spacer 100, rather than the absolute value of an angle formed by an initial velocity vector of an electron emitted from the second electron-emitting devices secondary closer to the spacer 100 and the line parallel to the longitudinal direction of the spacer 100.

Abstract: A method for manufacturing light emitting devices is provided. The method may reduce the inner pressure of a laminated image emitting device panel, thereby preventing failure of the panel. The method includes holding a first substrate with a lower chuck located in a vacuum chamber; holding a second substrate with an upper chuck located opposite the first chuck in the vacuum chamber; creating a high vacuum in the vacuum chamber; correcting positions of the first substrate and the second substrate; supplying gas having a temperature of about 50 to about 200° C. into the vacuum chamber; temporarily laminating the first substrate and the second substrate; venting the vacuum chamber; and bonding the first substrate and the second substrate. The panel is laminated after being filled with a heated gas and thus, when it is exposed to room temperature, the mobility of the gas decreases while reducing its initial inner pressure, thereby preventing panel failure.

Abstract: A pixel structure of display apparatus includes a first substrate and a second substrate. Several cathode structure layers are disposed on the first substrate. The second substrate is a light-transmissive material. Several anode structure layers are disposed on the second substrate, and are light-transmissive conductive materials. The first substrate faces to the second substrate, so that the cathode structure layers are respectively aligned with the anode structure layers. A separation structure is disposed between the first substrate and the second substrate, for respective partitioning the anode structure layers and the cathode structure layers to form several spaces. Several fluorescent layers are respectively disposed between the anode structure layers and the cathode structure layers. A low-pressure gas is respectively filled into the spaces.

Abstract: The invention concerns an illumination system, comprising a radiation source and a fluorescent material comprising at least one phosphor capable of absorbing a part of light emitted by the radiation source and emitting light of wavelength different from that of the absorbed light; wherein said at least one phosphor is a yellow red-emitting cerium-activated carbido-nitridosilicate of general formula (RE1?z)2?aEAaSi4N6+aC1?a:CeZ, wherein 0?a<1, 0<z?0.2, EA is at least one earth alkaline metal selected from the group of calcium, strontium and barium, and RE is a least one rare earth metal chosen from the group of yttrium, gadolinium and lutetium. The invention is also concerned with a red to yellow-emitting cerium 10 activated carbido-nitridosilicate of general formula (RE1?z)2?aEAaSi4N6+aC1?a:Cez wherein 0?a<1, 0<z?0.

Abstract: An OLED device, comprising: a first electrode; a conductive protective electrode comprising a transparent conductive oxide layer wherein the conductive protective electrode is a hermetic layer having a thickness less than 100 nm; one or more organic layers formed between the first electrode and conductive protective electrode, at least one organic layer being a light-emitting layer; and a patterned auxiliary electrode in electrical contact with the conductive protective electrode.

Abstract: A wideband retardation layer (or film) that can perform circular polarizing so that the retardation layer can be formed with an organic light-emitting device to be relatively thin and have a relatively high contrast with no reduction in brightness, and an organic light-emitting device including the retardation layer. The retardation film includes a base and a retardation layer including an alkali oxide layer grown to be inclined on a surface of the base, wherein the alkali oxide layer is disposed by slant-angle depositing alkali oxide on the surface of the base.

Abstract: An organic electroluminescent device. The organic electroluminescent device comprises a first barrier layer disposed on a substrate; organic electroluminescent elements disposed over the first barrier layer and encapsulated with a second barrier layer; and a getter layer disposed between the first and second barrier layers. Each of the first and second barrier layers includes an organic layer and an inorganic layer covering the top and sidewall surfaces of the organic layer, thus providing stacked inorganic sidewalls to hinder moisture and oxygen.

Abstract: According to an embodiment of the present invention, there is provided an organic electroluminescent device for emitting red light having an organic layer that includes a light-emitting layer and is provided between an anode and a cathode. The light-emitting layer contains a red light-emitting guest material and a host material that is composed of a polycyclic aromatic hydrocarbon compound having a skeleton with four- to seven-membered rings. Furthermore, a light-enhancing layer that contains a light-emitting guest material for generating light having a wavelength shorter than that of light emitted by the light-emitting layer is provided adjacent to the light-emitting layer.

Abstract: An object of the present invention is to provide a bottom emission type organic EL display device that has a light-emitting element unit thereof protected from being damaged by a stored desiccant, that has a long service life, and that exhibits excellent display characteristics of a high luminance and a high contrast. The solution is such that the organic EL display device includes a desiccant assembly which is disposed on the internal side of a sealing substrate and which has a cushioning member thereof jutted out of the surface of a desiccant.

Abstract: An electronic device can include a charge-selective layer and an organic active layer. In one embodiment, the electronic device can include a first pixel including a charge-transport layer, and a first portion of a first organic active layer and a second pixel including a second portion of the first organic active layer and substantially none of the charge-transport layer. In another embodiment, the process of forming the electronic device can include selectively depositing a charge-transport layer over the first electrode and not the second electrode, and depositing a second organic active layer over the first electrode and the second electrode. In yet another embodiment, the process can include liquid depositing a first charge selective layer over a first and second electrode and forming a second charge selective layer over the second electrode and not the first electrode.

Abstract: A substrate for an organic EL display including an insulating layer, in which release of a substance derived from a material for the insulating layer by heating at a temperature equal to or lower than a temperature obtained by subtracting 20° C. from a decomposition temperature of the material for the insulating layer is detected by mass spectrometric detection at an S/N ratio smaller than 3/1.

Abstract: The present invention provides an organic EL light-emitting apparatus that can compensate a voltage drop caused on a transparent electrode and that can prevent the occurrence of brightness unevenness caused by the voltage drop. A transparent electrode 2, an organic light-emitting functional layer 5, and a back electrode 6 are successively laminated on a light-transmitting substrate 1, and a sealing member 9 for sealing the transparent electrode, the organic light-emitting functional layer, and the back electrode is provided so as to accommodate them between the substrate 1 and the sealing member 9. A conductive layer 10 is formed on the sealing member 9, and conductive columnar members 4 are interspersedly formed between the conductive layer 10 and the transparent electrode 2 in the plane direction of the substrate 1. Accordingly, electric power is supplied to the transparent electrode 2 from the conductive layer 10 through the conductive columnar members 4.

Abstract: A structure for high performance light emitting electrochemical cells comprises at least two active layers of mixed ionic/electronic conducting materials, at least one of which is electroluminescent. The active layers are sandwiched between ion blocking electrodes, typically metal and/or transparent conducting oxide, that are electrically but not ionically conductive. Application of bias to the electrodes results in the polarization of ions at the electrodes thereby generating a field to drive the injection of electronic carriers into the active layer. The injected electron and holes recombine within the active layers to emit light. The ability to balance electron and hole injection in the design of such devices provides for optimal light emission efficiency.

Abstract: An organic light emitting diode (OLED) display device includes a substrate, a first electrode disposed on the substrate, an organic layer including an emission layer disposed on the first electrode, and a second electrode including stacked layers of Yb and Ag on the organic layer. A method of fabricating the organic light emitting diode (OLED) display device includes providing a substrate, forming a first electrode on the substrate, forming an organic layer including an emission layer on the first electrode, and forming a second electrode including stacked layers of Yb and Ag on the organic layer.

Abstract: An OLED device, comprising: a substrate; a first electrode formed over the substrate; one or more organic layers formed over the first electrode, at least one organic layer being a light-emitting layer; and a bi-layer electrode comprising a first transparent conductive protective hermetic layer formed over the one or more organic layers, and a second transparent conductive non-hermetic layer formed over the first transparent conductive protective hermetic layer.

Abstract: Embodiments of the invention relate to functionalized nanoparticle coating compositions. These coating can improve the light extraction efficiency of light emitting devices, including LEDs and OLEDs. In some embodiments, the coating can improve other properties such as anti-staining, abrasion and/or scratch resistance.

Abstract: There is provided an image display apparatus including: a first substrate having an electron-emitting device; a second substrate having an anode electrode that is opposed to the electron-emitting device; and a conductive layer that is provided on the side of a second face of the second substrate, the second face being an opposite face to a first face of the second substrate, the first face being located on the first substrate side, wherein a potential of the conductive layer is set to be lower than a potential of the anode electrode when displaying an image; and a surface resistance of the conductive layer is higher than a surface resistance of the anode electrode.

Abstract: A method of manufacturing a soft mold to shape a barrier rib, a method of manufacturing a barrier rib and a lower panel, and a plasma display panel (PDP) including the same. The method of manufacturing the soft mold includes: providing a metal mold on which a barrier rib pattern is formed, by alternating channels and projections; disposing a polymer sheet opposite the metal mold; pressing the metal mold into the polymer sheet, to form the soft mold, which has an inverted image of the barrier rib pattern formed on the surface thereof; and releasing the soft mold from the metal mold.

Abstract: Disclosed are a plasma display panel and a method of manufacturing the same. The plasma display panel includes a scan electrode and a sustain electrode formed on a glass substrate, each including a discharge ignition part for generating initial discharge and a discharge diffusion portion for diffusing discharge to the entirety using the initial discharge, and the plasma display panel includes a dielectric layer disposed on a upper side of the glass substrate to cover the scan electrode and sustain electrode.

Abstract: Provided is a display device having low driving voltage and high luminous efficiency. The display device includes a first substrate and a second substrate facing each other, a cell formed between the first and second substrates, a first electrode disposed between the first and second substrates, an emitter layer made of a nano-porous carbon (NPC) material and disposed on the first electrode to emit electrons into the cells in response to a voltage applied from the first electrode, a gas filled in the cells to generate ultra-violet rays whenever excited by the electrons emitted from the emitter layer, and a light-emitting layer formed at a region corresponding to the cell.

Abstract: A plasma display panel and a method of manufacturing the plasma display panel are disclosed. The plasma display panel includes a scan electrode, a sustain electrode, and a barrier rib formed on a glass, and an upper dielectric layer having a differential thickness formed on the glass. The upper dielectric layer covers the scan electrode and the sustain electrode. As the upper dielectric layer is far away from a discharge region portion between the scan electrode and sustain electrode, the width of the upper dielectric layer gradually increases. A distance between the scan electrode and the sustain electrode positioned within a discharge cell partitioned by the barrier rib is more than a height of the barrier rib.

Abstract: Row electrode pairs and column electrodes are provided between the front glass substrate and the back glass substrate. Magnesium oxide single-crystal particles, which are doped with aluminum and have characteristics of causing cathode luminescence having a peak within a wavelength range of 200 nm to 300 nm upon excitation by application of electron beams, are disposed in a position facing the discharge cells, and form part of a protective layer for a dielectric layer overlying the row electrodes and/or phosphor layers.

Abstract: Disclosed is a PDP and a manufacturing method therefor having improved display performance even if the PDP is of a fine-cell structure. A protective layer of the PDP is composed of an MgO film layer and an MgO particle layer that is made of MgO particles. The MgO particles are formed by burning an MgO precursor and satisfy that a/b?1, where a denotes a spectrum integral value in a wavelength region of a CL spectrum from 200 nm to 300 nm, exclusive of 300 nm, and b denotes a spectrum integral value in a wavelength region of the CL spectrum from 300 nm to 550 nm, exclusive of 550 nm. With provision of the MgO particle layer, the discharge characteristics of the protective layer improve (shorter discharge delay and less temperature dependence of the discharge delay). Consequently, the PDP is ensured to exhibit excellent display performance.

Abstract: “Discharge delay” and “dependence of discharge delay on temperatures” are solved by improving a protective layer, thus a PDP can be driven at a low voltage. Furthermore, the PDP can display excellent images by suppressing “dependence of discharge delay on space charges.” Liquid-phase magnesium alkoxide(Mg(OR)2) or acetylacetone magnesium ate whose purity is 99.95% and over is prepared, and is hydrolyzed by adding a small amount of acids to the solution. Thus, a gel of magnesium hydroxide that is a magnesium oxide precursor is formed. Burning the gel in atmosphere at 700° C. and over produces powder containing MgO particles 16a-16d having the NaCl crystal structure with (100) and (111) crystal faces or with (100), (110) and (111) crystal faces. By pasting the powder on a dielectric layer 7 or a surface layer 8, the MgO powder 16 is formed so as to serve as the protective layer.

Abstract: A plasma display panel (PDP) which can reduce the cost and time of manufacturing a plasma display device, and which can improve heat transfer efficiency of a plasma display device, comprises: a transparent front substrate; a rear substrate disposed parallel to the front substrate; an electromagnetic wave shielding layer fixed on the front substrate; a plurality of discharge cells defined by barrier ribs disposed between the front substrate and the rear substrate; a plurality of address electrodes extending over the discharge cells and disposed in a given direction; a rear dielectric layer covering the address electrodes; a plurality of fluorescent layers disposed in the discharge cells; a plurality of sustaining electrode pairs extending in a direction which crosses the given direction of the address electrodes; a front dielectric layer covering the sustaining electrode pairs; and a discharge gas filling the discharge cells.

Abstract: The invention relates to a high-pressure discharge lamp that has an electric power consumption of less than 50 watt and comprises a discharge vessel (1?) that is sealed on two sides and is made of a translucent ceramic material as well as electrodes (2?, 3?) which are disposed inside the discharge vessel (1?) and are used for generating a gas discharge. Xenon and metal halides are arranged within the discharge vessel (1?) which is embodied as a ceramic tube that has a uniform maximum inner diameter of 1.2 mm while the minimum cold filling pressure of the xenon amounts to 0.8 megapascal.

Abstract: The disclosed subject matter includes a filament electrode that can include a filament coil connected with a pair of lead wires with confidence. It is possible for a fluorescent lamp using the filament electrode to emit light with a wider range while located in a thin tube. The filament electrode can include a pair of connecting pipes, a pair of lead wires located parallel to each other, and a filament coil including two connecting parts. Each of the two connecting parts of the filament coil can attach to respective ends of the pair of lead wires via the pair of connecting pipes via pressure bonding so as not to contact the connecting parts of the filament coil with the ends of the pair of lead wires located in the pair of connecting pipes and so as to align the structures. Thus, the filament electrode can be used even in a thin glass or quartz tube and can provide an effective heat-shield operation.

Abstract: The present invention provides a multi-beam klystron apparatus. In the above-described multi-beam klystron apparatus, the magnetic field generating element of the electron-gun-unit-side magnetic field generating unit is disposed around the electron gun unit, and a plurality of magnetic gaps are provided in the inner peripheral surface of the magnetic pole, which covers the magnetic field generating element, in the direction of travel of the electron beams. Therefore, lines of magnetic force, which are parallel to the center axis of the radio-frequency interaction unit, can be generated. Thus, even the electron beam, which is generated from the location apart from the center axis of the electron gun unit, can be guided to the radio-frequency interaction unit in the same manner as in the location at the canter axis of the electron gun unit.