摘要:
A power supply apparatus for use with an arc utilizing device includes capacitors coupled in series between outputs of a rectifying unit, and inverters each of which is coupled across a respective one of the capacitors. Each inverter converts a DC voltage from the capacitor into a high frequency voltage and applies it to a respective one of transformers. A converter converts an output voltage from each transformer into a DC voltage for application to a load. An output detector generates a signal representative of an output current supplied to the load. A first voltage detector generates a signal representative of a first voltage to be applied to the inverters. A second voltage detector generates a signal representative of a second voltage across one of the capacitors. A voltage balancing unit generates control signals for determining the conduction periods of the respective inverters in accordance with the difference between the output representative signal and a preset desired-output-current representative signal. The voltage balancing unit modifies at least one of the control signals to change the conduction period of the inverter associated therewith in accordance with the difference between the first- and second-voltage representative signals.
摘要:
An input-side rectifier rectifies a commercial AC voltage from a commercial AC power supply connected to an input terminal and develops a rectified voltage between two output terminals. The rectified voltage is smoothed by a pair of capacitors. A switching arrangement connects the capacitors selectively in series and in parallel between the two output terminals. An inverter is associated with each of the capacitors. A high-frequency voltage from each of the inverters is voltage-transformed by a transformer. The high-frequency voltage from the transformer is converted into a DC voltage by a high-frequency-to DC converter for application to a load. When an AC voltage in a lower voltage group is applied to the input terminal, a switching control unit causes the switching arrangement to connect the capacitors in parallel, and when an AC voltage in a higher voltage group is applied to the input terminal, the switching arrangement is caused to connect the capacitors in series. The inverters include IGBTs having a withstanding voltage of about 800 V.
摘要:
A DC power supply apparatus includes a rectifier circuit which rectifies an input commercial AC voltage. The rectifier output voltage is smoothed in a smoothing capacitor. The DC voltage from the capacitor is converted to a high-frequency voltage in an inverter. The high-frequency voltage from the inverter is voltage-transformed by a transformer into a voltage-transformed, high-frequency voltage, which is then converted back into a DC voltage in a high-frequency-to-DC converter circuit. When an input commercial AC voltage is applied to the DC power supply apparatus, a pre-charging circuit pre-charges the smoothing capacitor from the input AC voltage. If a voltage having a magnitude larger than a prescribed value is applied to the DC power supply apparatus, an overvoltage protection circuit renders the rectifier circuit and the pre-charging circuit inoperative.
摘要:
A power supply apparatus for welders includes an input-side AC-to-DC converter for converting an input commercial AC voltage into a DC voltage, which is, in turn, converted to a high-frequency voltage in an inverter. The high-frequency voltage is transformed to a high-frequency voltage having a desired magnitude in a transformer. The transformed high-frequency voltage is then converted back to a DC voltage in an output-side high-frequency-to-DC converter. The DC voltage is developed between output terminals of the power supply apparatus. A current detector detects the current flowing through the output terminals and develops a detected-current representative signal. A voltage detector detects the voltage between the output terminals and develops a detected-voltage representative signal. A CPU has three control modes and controls, in a first mode, the inverter in such a manner that the current representative signal becomes equal to a reference-current representative signal. In a second mode, the CPU activates and, then, deactivates a high-frequency generator, which provides a high-frequency voltage between the output terminals, and, thereafter, performs the first mode of control. In a third control mode, the CPU controls the inverter in such a manner that the voltage representative signal becomes equal to a reference-voltage representative signal and also controls a wire feeder for feeding a wire to be connected to one of the output terminals.
摘要:
This light-emitting device includes a first electrode, a second electrode disposed opposite to the first electrode and a phosphor layer which is sandwiched between the first electrode and the second electrode and constituted by dispersing n-type semiconductor particles in a p-type semiconductor medium. A light-emitting device in another embodiment includes a first electrode, a second electrode disposed opposite to the first electrode and a phosphor layer which is sandwiched between the first electrode and the second electrode wherein a p-type semiconductor is segregated among the n-type semiconductor particles.
摘要:
A light emitting device includes a pair of electrodes facing to each other and a phosphor layer which is sandwiched between the pair of electrodes and includes phosphor particles placed therein. The phosphor particles include an n-type nitride semiconductor part and a p-type nitride semiconductor part, the n-type nitride semiconductor part and the p-type nitride semiconductor part are made of respective single crystals having wurtzite-type crystal structures having c axes parallel with each other, and the phosphor particles include an insulation layer provided to overlie one end surface out of their end surfaces perpendicular to the c axes.
摘要:
An optical head device includes a light source (30) configured to emit a light beam, a light collecting optical system configured to converge the light beam onto an information recording medium (10), a hologram element (20) configured to diffract the light beam reflected from the information recording medium (10), and a photodetector (40) having a plurality of detection regions configured to receive the light beam diffracted by the hologram element (20). The hologram element (20) has two diffraction regions (261 and 262) separated from each other by a straight line (260) extending in a radial direction of the information recording medium (10). At least one of the two diffraction regions has a pattern which introduces coma aberration in the radial direction. The light diffracted by the diffraction region having the coma aberration has coma aberration in the radial direction.
摘要:
There is provided a display device: a display unit including a plurality of scan electrodes arranged to extend in parallel to each other along a first direction, a plurality of data electrodes arranged to extend in parallel to each other along a second direction crossing the scan electrodes, and a plurality of pixels, each pixel at which a pair of the scan electrode and the data electrode cross each other, each pixel having a light emitting layer and a dielectric layer interposed between the scan electrode and the data electrode from a direction vertical to a face; and an erasing pulse supplying unit operable to supply attenuation voltage pulse, to the light emitting layer of each pixel, which starts at a voltage not more than an emission starting voltage at which the light emitting layer starts emission and in which polarity is alternately reversed between positive and negative.
摘要:
A light emitting device is provided with: a pair of an anode and a cathode that are opposed to each other; and a phosphor layer, composed of a plurality of phosphor particles, that is sandwiched between the paired anode and cathode, from direction that is perpendicular to main surfaces of the anode and the cathode, and in this structure, each phosphor particle is a nitride semiconductor phosphor particle having a wurtzite crystal structure that contains an n-type nitride semiconductor portion and a p-type nitride semiconductor portion, with the n-type nitride semiconductor portion being made in contact with the cathode and the p-type nitride semiconductor portion being made in contact with the anode, and the n-type nitride semiconductor portion and the p-type nitride semiconductor portion have the common c-axe in the respective crystal structures thereof made in parallel with each other, with the n-type nitride semiconductor portion and the p-type nitride semiconductor portion being made in contact with each other on a plane in parallel with the c-axe.
摘要:
Disclosed herein is a light-emitting device comprising a transparent or semi-transparent first substrate, a second substrate provided opposite to the first substrate, a transparent or semi-transparent first electrode provided on the first substrate, a second electrode provided on the second substrate so as to be opposite to the first electrode, and a light-emitting layer which contains a metal oxide semiconductor porous body, by the surface of which an organic light-emitting material is supported, and is provided between the first electrode and the second electrode.