Abstract: The present invention relates to a cathode ray tube, and more particularly to a cathode ray tube having a shadow mask for obviating doming phenomenon caused by thermal expansion and deterioration of color purity.

Abstract: A color cathode ray tube is disclosed, in which a purity correction means is installed in an outer side between an effective region and an effective screen, thereby decreasing distortion of the screen without deteriorating characteristics of a deflection yoke, and minimizing change of a misconvergence to improve color purity of the screen and productivity. To this end, the color cathode ray tube includes a panel 10 constituting a screen; a funnel 20 attached at the rear of the panel, having a bulb shape; a shadow mask 30 installed to be separated from the panel for choosing colors; and a purity correction means 60 installed to be close to the shadow mask. More preferably, the purity correction means 60 is attached in a range from a margin (S) of an effective screen of a panel to an effective end of the shadow mask 30 in an entire surface of the panel in which distortion of the screen is generated.

Abstract: A surface of a first grid electrode, which is located on a cathode side and is one of a plurality of electrodes for an electron gun used in an electrode gun assembly, is formed to be a rough surface having a higher degree of surface roughness than a surface of a second grid electrode located adjacent to the first grid electrode.

Abstract: A color cathode ray tube is disclosed, in which brightness is excellent, uniformity of brightness is improved, and characteristics of contrast are improved. To this end, the color cathode ray tube includes a panel (1) having an inner surface on which an electron bean emitted from an electron gun is irradiated and an outer surface exposed outwardly; black matrixes (10) formed at the inner surface of the panel (1) with a predetermined interval; a fluorescent film (20) composed of red, green, and blue fluorescencers among the black matrixes (10); and a black filter film (30) formed at the outer surface of the panel (1), or between the inner surface of the panel (1) and the fluorescent film (20), or between the inner surface of the panel 1 and the fluorescent film (20) with covering the black matrix (10).

Abstract: A cathode ray tube with a panel includes an inside surface having a designated curvature; a central portion having a transmission rate of 45-75%; and an outside surface being substantially flat with a flatness ratio (F) satisfying a mathematical formula of 1 F = Ro Sd × 1.

Abstract: A display device (10) (FIG. 1) which can be a plasma display panel or a highly loaded fluorescent lamp, comprises a hollow, translucent glass body (12) containing a medium capable of generating at least several wavelengths of UV radiation. A plurality of phosphors is disposed on the inside surface of the glass body, the plurality of phosphors emitting visible radiation upon exposure to the UV radiation. At least one of the plurality of phosphors is subject to degradation upon long-term exposure to one of the at least one of several wavelengths of UV radiation that may be available. The at least one of the plurality of phosphors subject to degradation is installed (FIG. 2) adjacent the inside surface (14) of the glass body to form a first layer (16); and, the remainder of the plurality of phosphors is disposed on the first layer to form a second layer (18), the second layer not being subject to long-term degradation upon exposure to the UV radiation. In some embodiments (FIG.

Abstract: Disclosed is a new and useful discharge lamp for use in applications, such as tanning and technical lighting, and a method of making the same. The discharge lamp includes, inter alia, a vitreous tube having an axial length, a base phosphor coating applied on the interior of the tube along the entire axial length, and at least one phosphor over-coat applied over the base phosphor coating in one or more axial regions of the vitreous tube. The phosphor over-coat is applied to less than the total length of the vitreous tube. In a representative embodiment, the vitreous tube has an outer periphery which is smooth, but in alternate embodiments, a helical groove path is formed therein over at least a portion of the axial length.

Abstract: Disclosed is an image display apparatus having a construction such that ultraviolet rays irradiated from a second substrate side are prevented from propagating through a first substrate to reach its display area by providing a picture-frame resin film for shielding ultraviolet rays on that area of the first substrate that is to be sealed to the second substrate with a sealant. Thereby, when the sealant for sealing the substrates is cured by irradiation of ultraviolet rays, photo deterioration of organic materials constituting emitting layered products and semiconductor layers constituting active elements both of which are formed on the display area may be prevented, and a high-reliability and high-performance image display apparatus may be realized.

Abstract: The object of the present invention is to form the fine structure on a cathode surface homogeneously and reproducibly to realize the increased emission current value and stability with a simple process in the electron emission element forming process. An electron emission part of an electron emission element that is a crystalline thin film of electron emissive material formed in self-aligning fashion by means of a laser ablation process, in which a laser beam is irradiated onto a target material and the material ejected and emitted from the target material is deposited to form a thin film on a substrate facing to the target, is used as the thin film electron source. The above-mentioned structure is effective to realize the low electron emission threshold value and the increased emission current value and stability, and realize the reduced cost with the structure that is simpler than the conventional structure.

Abstract: An active matrix organic light emitting diode display and a fabrication method of the same. A substrate having a display area and a non-display area is provided. A plurality of pixel structures is formed in the display area, and a plurality of transparent conductive lines to electrically connect the pixel structures are formed on the substrate. The transparent conductive lines extend from the display area to the non-display area. A photosensitive glue is formed at a periphery of the display area, and a cap is formed to cover the display area. The cap is adhered to the substrate using the photosensitive glue. A radiation step is performed on a rear surface of the substrate to cure the photosensitive glue. A driving chip electrically connected to the pixel structures via the transparent conductive lines is formed in the non-display area.

Abstract: To minimize the variability in the emitted light color and improve the unevenness of color tone, a light emitting device comprises a light emitting element and a fluorescent substance that is excited by the light emitting element, wherein the light emitting element has an emission spectrum in a region from ultraviolet to visible light of short wavelengths, and the fluorescent substance has an emission spectrum that includes two or more emission peaks with at least two peaks of the two or more peaks being in the relation of complementary colors of each other.

Abstract: An organic light emitting device that may have mixed organic layers is provided. A method of fabricating such an organic light emitting device is provided. A first organic material is solution deposited to form a patterned organic layer over a first electrode. A second organic material is deposited, by means other than solution processing, on and in physical contact with the first organic layer to form a second organic layer. The second organic layer forms a blanket layer over the first organic layer. A second electrode is then deposited over the second organic layer.

Abstract: The present invention relates to an organic electroluminescent device comprising a gradual organic electroluminescent layer AxByCz inserted between the anode electrode (may include hole injection layer) and the cathode electrode, wherein A, B, and C are mediums capable of transporting holes, electron and injecting electron respectively, and x, y, z denotes the content of medium A, B, and C respectively. The gradual layer with different materials combined is a mixed continuous organic medium without heterojunctions, wherein the sum of x, y, and z is 100%. Moreover, x has a maximum value adjacent the anode electrode, and the sum of y and z has a maximum value adjacent the cathode electrode, while the medium C is an electron injection component comprising either a low work function metal, metal compound, metal alloy, or even organic material with high electron affinity.

Abstract: Electric lamp assembly comprising a sealed, light-transmitting envelope having a preferably generally spherical or bulbous portion and a press seal, a filament in the interior of the bulbous portion, the filament having a pair of electrical leads sealed within the press seal and extending exteriorly therefrom. The bulbous portion also includes at least one elongated member such as a lead normally present for a second filament of a double filament lamp, preferably two such members, but is devoid of the second filament. The elongated member or members also are sealed in the press-seal, and help provide stability to the assembly.

Abstract: An electrode plate, a method of manufacturing the same, a gas discharge panel using an electrode plate, and a method of manufacturing the same are provided by incorporating a relatively simple structure, which can keep electrodes formed on a plate from peeling or becoming misaligned. In the electrode plate, at least one electrode is formed and adhered to a main surface of a plate by a thick film or thin film formation method, wherein of all ends of the electrode, at least an end opposite to an end at a power supply point is adhered to the main surface of the plate with stronger adhesion than the other parts of the electrode.

Abstract: In a flat display device having a pair of substrates for defining a gas discharge space in which a gas used to generate discharge luminance is sealed, means for absorbing or reflecting near infrared rays is included.

Abstract: A light source device in which the operating characteristic of the auxiliary light source can be improved, in which the starting property within the main discharge vessel is extremely advantageous and which has high reliability with respect to vibration resistance and impact strength without the disadvantage of a cost increase due to the complicated arrangement of the light source device, without reducing the proportion of good articles in the manufacture of the products, and without reducing the quality of the discharge lamp is achieved using a main discharge lamp mounted in a reflector with an auxiliary light source tightly held by the reflector or components which are adjacent to the reflector and without contact with the main discharge vessel.

Abstract: The invention provides a method for sealing arc tubes while preventing cracking of the tube. The method comprises sealing a pair of electrodes on the arc tube in a furnace. A heat shield structure is used to reduce the thermal gradient generated by the sealing process. The heat shield comprises alternating layers of thermally conducting materials and thermally non-conducting materials.

Abstract: The invention relates to metal halide lamps having a discharge vessel with a ceramic wall. The discharge vessel encloses a discharge space comprising an ionizable gas filling and, in addition to Hg, also an alkali iodide of Na or Li or a combination of both. According to the invention, the filling also comprises TbI3 or GdI3 or a combination thereof.

Abstract: A fluorescent lamp includes two glass outer tubes (6, 7), a bridge junction (8), and first glass inner tubes (9, 10). One end of each of the glass outer tubes is closed, and the other end is sealed with stems (4, 5) for supporting electrodes (13). A phosphor is applied to the inside surface of each of the glass outer tubes. The bridge junction connects the glass outer tubes at the other end portion to form a discharge space inside the glass outer tubes. The first glass inner tubes are provided in the glass outer tubes, respectively. A phosphor is applied to the surface of each of the first glass inner tubes. One end of each of the first glass inner tubes is open and disposed at the closed ends of the glass outer tubes, and the other end is sealed with the tips of the stems so that the electrodes are positioned in the first glass inner tubes.

Abstract: A magnetron includes an anode cylinder and anode vanes; a cathode having a filament; a condenser, a choke coil, and a plurality of leads for providing power to the filament; a plurality of magnets, pole pieces, and a yoke for forming a magnetic circuit; an antenna feeder and an antenna cap for transmitting a generated microwave outside of the magnetron; and a plurality of joints formed of a joining material between a metal component and a ceramic component of the magnetron. The joining material is diffused between the metal component and the ceramic component, to infiltrate into an inner part of the ceramic component directly, thereby joining the metal and ceramic components, and thereby also improving a reliability of a magnetron, facilitating a simple component assembly process and a simple magnetron fabrication process, permitting simplification of the fabrication process and reduction of a fabrication cost, and saving equipment cost as a high temperature furnace can be dispensed with.

Abstract: A plasma device includes a slot antenna (30) for supplying a high frequency electromagnetic field (F) supplied through a feeding part into a processing vessel (11). The feeding part has a cavity (35) for forming a resonator and converting the fed high frequency electromagnetic field (F) into a rotating electromagnetic field and supplying the rotating electromagnetic field to the slot antenna (30).

Abstract: A high intensity light source arrangement, which can prolong the service life span of the high intensity light source arrangement by better dissipating and reducing the heat generated, includes a luminary unit comprising a luminary circuit, at least a terminal electrically connected to the luminary circuit, and at least a luminary element adapted for electrifying with the terminal to emit light; a heat dissipation unit supporting the luminary unit and dissipating heat generated from the luminary unit; and a base housing for supporting the heat dissipation unit thereon including an electric input connector electrically connecting to the luminary unit.

Abstract: The operating method is based on the simultaneous application of FM and AM, and is distinguished by passing through three operating states, specifically a warm-up phase, an impressing phase and the continuous operation.

Abstract: Proposed is a method of operating a gas discharge lamp, preferably a fluorescent lamp (10), in which the lamp is at least partly operated with a dc voltage component and voltage pulses are superimposed on that dc voltage component which can be reduced to zero. A power supply unit (11) for carrying out the method is designed in such a way that a running voltage source (13) for supplying the dc voltage and a pulse source (12) for supplying the voltage pulses are provided or can be connected.

Abstract: An LED lamp comprising a tubular wall circular, oval, or multi-faceted in cross-section having tubular wall ends. At least one electrical string mounted within the tubular wall extends between the tubular wall ends with at least one LED electrically mounted thereto. Electrical circuit means providing power to at least one LED from the ballast assembly of a fluorescent lamp fixture. Electrical circuit means include an LED circuit including at least one electrical string each having one LED or a plurality of LEDs connected in series thereto. The at least one electrical string can further include two electrical strings in parallel or a plurality of parallel electrical strings. Means for suppressing voltage delivered from the ballast assembly to an LED operating voltage within the design capacity of said plurality of LEDs in electrical connection with the electrical circuit means.

Abstract: A lighting circuit for an HID lamp causing no erroneous operation of a lighting circuit even when counter-electromotive force is generated due to the inductance in the wirings when the lighting circuit and the HID lamp are located at a long distance and not causing flicker even when the inter-electrode resistance of the HID lamp differs depending on the direction of the application voltage, comprising a control section (C) adapted, upon application of an AC rectangular wave voltage to an HID lamp (1) by a full-bridge type inverter (9), for detecting a resistance value in a positive direction and a resistance value in a negative direction of the HID lamp (1) corresponding to the direction of the polarity of the AC rectangular wave voltage, setting the duty ratio between the positive direction and the negative direction of the AC rectangular waveform voltage so as to be in an inverse proportion with the magnitude for each of the resistance values, and switching each of the switching elements (12A-12D) of the in

Abstract: The invention concerns an energy-saving light marking device with low power consumption comprising a head transformer (10) whereof the primary winding (12) is powered by an alternating current source and a plurality of marking lamps in series (14-1 to 14-3) connected to the terminals of the secondary winding (13) of the head transformer, each of the marking lamps consisting of a fluorescent lamp (16-1 to 16-3) powered by the secondary winding of a second transformer (18-1 to 18-3), the primary windings of all the secondary transformers of the marking lamps being connected in series between the terminals of the secondary winding (13) of the head transformer. According to the main characteristic of the invention, the starting of each of the fluorescent lamps (16-1 to 16-3) is provided by the voltage surge generated at the terminals of the secondary winding of the secondary transformers (18-1 to 18-3) when the primary winding of the secondary transformers is powered while the lamps are not yet started.

Abstract: A control system and method for simultaneously regulating the operation of a plurality of different types of switching power converters. The system utilizes in regulating the power converters sampled data and nonlinear feedback control loops.

Abstract: Apparatus and method are provided for using a multi-element field emission cathode in a color cathode ray tube. The field emission cathode may have from four to ten field emission arrays linearly arranged. The arrays are preferably formed from carbon-based material. An electron gun assembly focuses electron beams from each array on to a phosphor stripe or dot on the screen of the cathode ray tube. Deflection apparatus moves the beam from each field emission array according to clock signals. Clock signals also turn on or turn off voltage to contacts controlling electron current from the array. Values of voltage applied, determined by a video signal, determine the intensity of electron current from each array, which controls the intensity of the light emitted by each color stripe or dot of phosphor on the phosphor screen.

Abstract: One aspect of the invention is embodied in a machine for wrapping a heater wire around a cold cathode fluorescent lamp (CCFL). The machine includes means for holding a CCFL, means for guiding a heater wire, and means for moving the holding means in relation to the guiding means for the purpose of wrapping a heater wire around a CCFL that is held by the holding means. Another aspect of the invention is embodied in a CCFL wrapped with a heater wire. The process used to wrap the CCFL involves inserting the CCFL into a socket of an automated machine and feeding the heater wire into a heater wire guide of the automated machine. The socket is then moved in relation to the heater wire guide, by means of the automated machine, for the purpose of wrapping the heater wire around the CCFL.

Abstract: A window lifter system and method coordinates closing of multiple windows by detecting when more than one window pane is approaching a fully closed position and moving one window pane to only an approximately closed position while the other window pane is moved to the fully closed position. By staggering the closure of window panes to the fully closed positions, the system and method provides the illusion that all of the window panes are being closed at the same time while avoiding voltage drops in the vehicle power supply caused by excessively high blocking currents generated when multiple window panes are moved to the fully closed position.

Abstract: A guided stage mechanism suitable for supporting a reticle in a photolithography machine includes a stage movable in the X-Y directions on a base. Laterally surrounding the stage is a rectangular window frame guide which is driven in the X-axis direction on two fixed guides by means of motor coils on the window frame guide co-operating with magnetic tracks fixed on the base. The stage is driven inside the window frame guide in the Y-axis direction by motor coils located on the stage co-operating with magnetic tracks located on the window frame guide. Forces from the drive motors of both the window frame guide and the stage are transmitted through the center of gravity of the stage, thereby eliminating unwanted moments of inertia. Additionally, reaction forces caused by the drive motors are isolated from the projection lens and the alignment portions of the photolithography machine.

Abstract: A method and an apparatus for precisely controlling the rotation speed of a spindle motor in an optical system according to a given condition are provided. The method involves counting in response to a clock signal widths of first and second logic states of an input signal, which varies with rotation speed of the spindle motor, when an operation control command is issued, comparing a predetermined reference value with a count value for one check cycle, and outputting the comparison result; and controlling the constant linear velocity of the spindle motor in response to the comparison result.

Abstract: A device for supplying energy by means of a first DC voltage source e.g. in the form of a DC voltage bus, a drive system comprising several electric motors is connected to said DC voltage bus. The electric motors are comprised e.g. in a number of yarn feeding devices co-acting with a weft insertion system in a shuttleless weaving machine for producing a woven fabric having a multi-colour pattern. The electric motors operate with energy consumption function phases (start and acceleration) and with energy generating function phases (deceleration or braking). The first DC voltage source is associated with at least one second DC voltage source via a variable voltage converter.

Abstract: The present invention provides a mirror device motor control circuit that can reliably stop a mirror at predetermined positions with a simple configuration. In the control circuit of the invention, part of a lock current flowing to the motor flows to a base terminal of a transistor. Thus, as long as a voltage corresponding to the lock current is equal to or greater than a specific value, this voltage is applied to the base terminal of the transistor, whereby between a collector terminal and an emitter terminal becomes conductive, and the current flowing to a gate of a MOSFET is grounded via the collector terminal and the emitter terminal of the transistor. For this reason, when the lock current flows, conduction between a drain terminal and a base terminal of the MOSFET is released and a drive current of the motor is cut off.

Abstract: A method for controlling a voltage mode controlled electric machine comprising: receiving a torque value representative of a desired torque; obtaining a speed value indicative of a rotational velocity of the electric machine; acquiring a phase advance value indicative of a desired phase advance angle; generating a voltage command responsive to the torque value, the position value; the generating is responsive to the torque value, the speed value, and the phase advance value.

Abstract: In a current detection system for detecting phase currents of an electric motor driven through a power converter adapted for carrying out ON/OFF control of bridge-connected plural switching elements in accordance with a predetermined excitation pattern to convert direct current into, e.g., three phase alternating currents, there are provided a current detecting element connected to the direct current side of the power converter and serving to provide a signal corresponding to current value, a waveform changer for changing the predetermined excitation pattern so that a signal directly or indirectly corresponding to the phase currents is produced at the current detecting element, and a current detector for detecting phase currents of the electric motor on the basis of the signal produced at the current detecting element and the changed excitation pattern. As a result, detections of phase currents of the electric motor can be carried out by using single current detecting element.

Abstract: A hybrid power system has two voltage sources, a variable DC power source, and a second power source, connected through selection components to a common node. The variable DC power source may be a solar power source and the second source may be an AC grid. The selection components, e.g. blocking diodes, SCRs, or relays, allow one or both of the sources to be connected to the node depending on the voltages produced by the sources. A variable speed drive and load may be connected to the node.

Abstract: A bicycle power supply and charger system is disclosed to include a dynamo adapted to generate power supply upon running of the bicycle, a rectifier output voltage regulator adapted to convert output power of the dynamo into the desired DC output power, an electric connector adapted to receive a personal mobile electric apparatus and to transmit the DC output power from the rectifier output voltage regulator to the personal mobile electric apparatus, and a battery charger connectable to the electric connector and adapted to charge the battery of a personal mobile electric apparatus.

Abstract: A battery pack is provided. In the battery pack, batteries and a circuit are completely separated. A battery block includes a battery package that can house one or more of the batteries. The circuit block includes a measurement/protection circuit that has a measurement function about use conditions or performance of the batteries or a function to protect the batteries that is housed in a circuit package wherein the battery block and the circuit block are fit in and housed inside of an outer case. The battery block and the circuit block can be independently removed and replaced from the outer case. In this regard, where a defect of the battery block or the circuit block occurs in a manufacturing process, the block with the defect can be replaced on its own. When the batteries in the battery block are deteriorated or consumed, the battery block can be replaced on its own. An electrolytic solution leaked from the batteries remains in the battery package.

Abstract: An adapter for a power tool battery. The adapter enables a battery having a first configuration, such as a “slide-on” configuration, to be used with a power tool and/or to be charged by a battery charger having a second configuration, such as a “tower” configuration. The adapter may also enable a battery having one general configuration, such as a “slide-on” configuration or a “tower” configuration, and a first connecting structure to be used with a power tool and/or to be charged by a battery charger having the same general configuration, such as the “slide-on” configuration or the “tower” configuration, respectively, and a second connecting structure different than the first connecting structure.

Abstract: A battery is charged by using in series a constant-voltage DC power supply with current limit function and a constant voltage circuit which has a differential comparator circuit and whose current limit value is variable. Following a period of charging with the current of current limit value by the constant-voltage DC power supply, a period is provided in correspondence with the state of charging of the battery, for charging with a current limit value of the constant voltage circuit which is smaller than that current limit value. The detection of the charging state of the battery is effected by a comparison between a current value of a current source of a differential comparator circuit and a differential output of that differential comparator circuit. It enables to reduce electric power consumed by the control transistor of the constant voltage circuit and to reduce the allowable loss required for the control transistor.

Abstract: Adaptive battery conditioning employs battery chemistry determination to establish how, when and whether to condition a battery. As a result, the conditioning is optimized for the determined battery chemistry. Further, conditioning of a battery that is not conditionable, such as a nonrechargeable battery, is prevented. A device determines battery chemistry in situ from a measurement of a characteristic of an installed battery, and conditions the installed battery in situ. The device can be a battery-powered consumer electronic device or a battery charging and conditioning system that is independent of an electronic device that uses the conditioned battery. A method of adaptive battery conditioning includes determining a chemistry of a battery from a measurement of a battery characteristic, and conditioning the battery according to the determined battery chemistry.

Abstract: This invention includes a thermally stable, low-cost charging circuit for rechargeable batteries. The circuit includes a thermal control circuit that employs a temperature dependent component such as a thermistor or positive temperature coefficient device. The temperature dependent device is thermally coupled to a charging pass element, which is typically a power transistor. When the transistor enters a danger zone, which is a region of operation characterized by elevated power dissipation in the pass element, the thermal control circuit is actuated to regulate the pass element in a constant power mode until the circuit exits the danger zone.

Abstract: A power supply (1) for a pulsed load (2) includes a first energy storage device in the form of a battery (3) which is in parallel with a second energy storage device in the form of a supercapacitor (4). Battery (3) and supercapacitor (4) are respectively modelled as: an ideal battery (7) in series with an internal resistance (8); and an ideal capacitor (9) in series with an equivalent series resistance (ESR) (10). Through use of a supercapacitor (4) having a low ESR with respect to the resistance (8), the power supply (1) facilitates continuity of supply to load (2). That is, during peak demand more of the load current will be supplied by supercapacitor (4) due to the lower ESR. Moreover, during times of lower load current demands the battery recharges the supercapacitor. This reduces the peak current needed to be provided by the battery and thereby improves battery longevity.

Abstract: Apparatus for the transfer of electric power produced by at least one multi-phase alternating-current generator (1) or generator unit into at least one multi-phase alternating-current power network (UU,UV,UW), said apparatus comprising at least one control unit (4), at least one non-controlled rectifier bridge (2), a direct-current intermediate circuit and at least one controlled inverter bridge (3) for supplying d.c.

Abstract: DC input energy is converted into DC output voltage which is used to create an output RF waveform for use in electrosurgery, by the use of a switched current mode high-voltage power supply. Pulses of input current are switched through a conversion transformer and the energy content of each pulse is converted into the DC output voltage. The time widths of the input current pulses are regulated relative to the DC output voltage, the magnitude of the current within each input current pulse, and in relation to maintaining a plurality of different selected operational conditions. The rate at which the input current pulses are converted is changed relative to the level of the DC output voltage.

Abstract: A device is described for the correction of the power factor in power supply units with forced switching operating in transition mode. Said device comprises a converter and a control device coupled with said converter so as to obtain a regulated voltage on the output terminal from an alternating network input voltage. The converter comprises a power transistor whilst the control device comprises a pilot circuit suitable for determining the switch-on time and the switch-off time of the power transistor. The control device furthermore comprises control means coupled with said pilot circuit and with said converter and capable of prolonging the switch-on time of the power transistor at the instants of time wherein the alternating network voltage substantially takes on the value zero.

Abstract: method and apparatus for providing a photomultiplier power supply having a transformer with multiple secondary windings forming cells that can provide voltage ratios to a photomultiplier element in which the ratios can be adjusted by the method of connection to the cell, by the number of turns in the transformer, or by a combination of both.